This document discusses laser-based manufacturing processes for Molded Interconnect Devices (MIDs) and methods for testing the adhesion strength of their metallization. It describes several laser-based structuring techniques for MIDs, including additive processes like Laser Direct Structuring (LDS) and ADDIMID, as well as semi-additive and subtractive processes. The document focuses on the widely-used LDS process and discusses suitable LDS parameters for metallization. It also outlines common tests for measuring adhesion strength, such as peel, shear, and hot pin pull tests, and assesses their suitability. The document aims to provide an overview of laser-based MID manufacturing and qualification methods regarding metallization adhesion
Investigation of Deformation Analysis of Glass Fiber Reinforced Polymer Injec...Dr. Amarjeet Singh
Warpage is one of the most crucial problems in injection molded products. Factors affecting warpage include Material, Part geometry, gate location, Fiber content & orientation, temperature, etc. Since many factors cause shrinkage and warpage, it is very difficult to distinguish the predominant factor. In the present study, we have focused on contribution of fiber content on warpage of injection molded part. Basic requirement of the part is flatness at sealing area within given tolerance. The required flatness should be within a given tolerance for effective functioning of the component. Flow simulation software has been used to assess the effect of fiber content on warpage and in turn flatness of the component.
FEM Analysis of Stress Predication of Aluminum Wire Rod in Drawing OperationIRJET Journal
This document analyzes aluminum wire drawing operations to understand causes of wire breakage. Finite element analysis is conducted using ANSYS to simulate wire stresses, strains, die stresses, and temperatures at critical drawing stages. The analysis considers different friction conditions to find optimal parameters that minimize defects and breakage. Material properties of the aluminum alloy wire and polycrystalline dies are defined. Simulation results reveal plastic deformation patterns and maximum stresses under various lubrication conditions to suggest preventative measures and reduce breakage during drawing.
Technology for Plastic Mold Tooling - Direct Metal Deposition HCL Technologies
This whitepaper highlights the benefits of DMD(Direct Metal Deposition) technology in mold cycle time reduction. It presents a comparative analysis conducted for cycle time performance of a mold consisting of a conventionally machined tool steel insert to a mold fitted with a Chromium Copper insert with a coating of tool steel deposited by the DMD process.
An overview of experimental investigation of near dry electrical discharge ma...iaemedu
The document provides an overview of experimental investigations into the near-dry electrical discharge machining (EDM) process. Near-dry EDM uses a mixture of gas and small amount of liquid dielectric fluid. It aims to overcome issues with wet EDM like pollution and dry EDM like debris reattachment. The document compares near-dry EDM to wet and dry EDM in terms of factors like material removal rate, surface roughness, gap distance, and debris deposition. It also examines the effects of electrical parameters, machining parameters, electrode material, and dielectric medium on material removal rate and surface roughness. The document concludes that near-dry EDM shows potential advantages but further optimization of parameters is needed to make it a cost-
This document reviews the direct metal deposition (DMD) process and the effects of various process parameters on the geometrical characteristics of parts produced. It discusses how the laser power, beam diameter, scanning speed, powder flow rate, and other parameters influence characteristics like clad height, width, roughness, and dilution. Several studies that developed models and experiments to relate parameters to outcomes are summarized. In general, increasing laser power or powder flow rate tends to increase clad height while increasing scanning speed decreases height. Process maps and models have been created but further research is still needed to better understand and control the complex interactions in the DMD process.
CFD SIMULATION OF SOLDER PASTE FLOW AND DEFORMATION BEHAVIOURS DURING STENCIL...ijmech
In 20th century, Electronics elements have become most significant part of the regular life. The main heart
of electronic element is PCB which supports and manages mostly machines and equipments these days.
Therefore manufacturing of board and assembly of electronic elements is one of the crucial and significant
objectives for most of the companies. Better life of PCB’s depends on electronic elements and its assembly
with board. Solder paste is used as adhesive material for assembly purpose. It is deposited on board using
stencil and electronic elements are mounted on it and heated for strong bond.
This study investigates on factors affecting stencil printing process due to variation in squeegee speed and
density of solder paste. This study is based on computational fluid dynamics virtual simulation. Prototype is
developed for modelling purpose and simulation software is used to simulate the flow behaviour of solder
paste during stencil printing process.
IRJET- Analysis of 2D Auxetic Metamaterial as a Variable Macro and Micro ...IRJET Journal
This document summarizes research into using 2D auxetic metamaterials as variable mechanical filters. Auxetic structures were created using 3D printing, rubber sheets, and silicone casting to experimentally determine their Poisson's ratios and filtering capabilities. The auxetic structures showed lateral expansion under tension and were able to function as mechanical sieves, with the potential to vary the size of filtered particles by applying stress. The research aims to further explore using re-entrant auxetic metamaterials as molecular filtration membranes whose pore size could be controlled.
The document discusses a study that investigated the relationship between the quality of arc welding and an artisan's mode of training. The study involved 36 artisans with secondary education and 36 with primary education from both formal and informal training backgrounds in urban and rural areas. They fabricated steel products which were assessed for welding quality. The study found that informally trained urban artisans with secondary education had the highest quality, while informally trained rural artisans with primary education had the lowest. Formal training was found to significantly improve quality for rural but not urban artisans. The findings provide evidence that training can improve product quality, especially for rural artisans.
Investigation of Deformation Analysis of Glass Fiber Reinforced Polymer Injec...Dr. Amarjeet Singh
Warpage is one of the most crucial problems in injection molded products. Factors affecting warpage include Material, Part geometry, gate location, Fiber content & orientation, temperature, etc. Since many factors cause shrinkage and warpage, it is very difficult to distinguish the predominant factor. In the present study, we have focused on contribution of fiber content on warpage of injection molded part. Basic requirement of the part is flatness at sealing area within given tolerance. The required flatness should be within a given tolerance for effective functioning of the component. Flow simulation software has been used to assess the effect of fiber content on warpage and in turn flatness of the component.
FEM Analysis of Stress Predication of Aluminum Wire Rod in Drawing OperationIRJET Journal
This document analyzes aluminum wire drawing operations to understand causes of wire breakage. Finite element analysis is conducted using ANSYS to simulate wire stresses, strains, die stresses, and temperatures at critical drawing stages. The analysis considers different friction conditions to find optimal parameters that minimize defects and breakage. Material properties of the aluminum alloy wire and polycrystalline dies are defined. Simulation results reveal plastic deformation patterns and maximum stresses under various lubrication conditions to suggest preventative measures and reduce breakage during drawing.
Technology for Plastic Mold Tooling - Direct Metal Deposition HCL Technologies
This whitepaper highlights the benefits of DMD(Direct Metal Deposition) technology in mold cycle time reduction. It presents a comparative analysis conducted for cycle time performance of a mold consisting of a conventionally machined tool steel insert to a mold fitted with a Chromium Copper insert with a coating of tool steel deposited by the DMD process.
An overview of experimental investigation of near dry electrical discharge ma...iaemedu
The document provides an overview of experimental investigations into the near-dry electrical discharge machining (EDM) process. Near-dry EDM uses a mixture of gas and small amount of liquid dielectric fluid. It aims to overcome issues with wet EDM like pollution and dry EDM like debris reattachment. The document compares near-dry EDM to wet and dry EDM in terms of factors like material removal rate, surface roughness, gap distance, and debris deposition. It also examines the effects of electrical parameters, machining parameters, electrode material, and dielectric medium on material removal rate and surface roughness. The document concludes that near-dry EDM shows potential advantages but further optimization of parameters is needed to make it a cost-
This document reviews the direct metal deposition (DMD) process and the effects of various process parameters on the geometrical characteristics of parts produced. It discusses how the laser power, beam diameter, scanning speed, powder flow rate, and other parameters influence characteristics like clad height, width, roughness, and dilution. Several studies that developed models and experiments to relate parameters to outcomes are summarized. In general, increasing laser power or powder flow rate tends to increase clad height while increasing scanning speed decreases height. Process maps and models have been created but further research is still needed to better understand and control the complex interactions in the DMD process.
CFD SIMULATION OF SOLDER PASTE FLOW AND DEFORMATION BEHAVIOURS DURING STENCIL...ijmech
In 20th century, Electronics elements have become most significant part of the regular life. The main heart
of electronic element is PCB which supports and manages mostly machines and equipments these days.
Therefore manufacturing of board and assembly of electronic elements is one of the crucial and significant
objectives for most of the companies. Better life of PCB’s depends on electronic elements and its assembly
with board. Solder paste is used as adhesive material for assembly purpose. It is deposited on board using
stencil and electronic elements are mounted on it and heated for strong bond.
This study investigates on factors affecting stencil printing process due to variation in squeegee speed and
density of solder paste. This study is based on computational fluid dynamics virtual simulation. Prototype is
developed for modelling purpose and simulation software is used to simulate the flow behaviour of solder
paste during stencil printing process.
IRJET- Analysis of 2D Auxetic Metamaterial as a Variable Macro and Micro ...IRJET Journal
This document summarizes research into using 2D auxetic metamaterials as variable mechanical filters. Auxetic structures were created using 3D printing, rubber sheets, and silicone casting to experimentally determine their Poisson's ratios and filtering capabilities. The auxetic structures showed lateral expansion under tension and were able to function as mechanical sieves, with the potential to vary the size of filtered particles by applying stress. The research aims to further explore using re-entrant auxetic metamaterials as molecular filtration membranes whose pore size could be controlled.
The document discusses a study that investigated the relationship between the quality of arc welding and an artisan's mode of training. The study involved 36 artisans with secondary education and 36 with primary education from both formal and informal training backgrounds in urban and rural areas. They fabricated steel products which were assessed for welding quality. The study found that informally trained urban artisans with secondary education had the highest quality, while informally trained rural artisans with primary education had the lowest. Formal training was found to significantly improve quality for rural but not urban artisans. The findings provide evidence that training can improve product quality, especially for rural artisans.
HEALTH CENTER NEEDS MANAGER WITH GRADUATE OF PROFESSION OF PUBLIC HEALTH GENE...IAEME Publication
An additional cost of health insurance paid by the government has increased every
year. Theoretically, this is due to curative services have been more and more dominant.
The one problem might be due to different views between 2 organizations concerning
public health.
This document summarizes a research paper about modular construction in the UK healthcare sector. It examines case studies of three module manufacturers and aims to define modularity in construction, distinguish modular from traditional construction, and explore the modular design process. Key findings suggest modular construction can provide benefits like reduced time and costs compared to traditional building, though barriers like transportation constraints remain. The summary explores how the case study companies define and approach modular construction.
IRJET- Optimization of Laser Transmission Welding Process Parameters using Si...IRJET Journal
This document summarizes research on optimizing the laser transmission welding process parameters for polypropylene and polypropylene composite materials. Statistical methods like the Taguchi method and ANOVA were used to analyze how laser power, scanning speed, number of passes, and other parameters influence weld strength and width. Both single objective and multi-objective optimization techniques were applied. The optimal parameter ranges were determined to produce high quality welds without defects. SEM analysis examined the weld cross-sections and surfaces. Overall, the study investigated how to optimize the laser transmission welding process for polypropylene composites.
Study in Physical and Mechanical Properties of Renewable Aluminum Foil-Filled...prawitjitiyakron
This research studies the potential of a renewable material,
aluminum foil, as filler in high density polyethylene (HDPE).
The filler was used in range of 0-40% by weight. Aluminum
foil/HDPE compounding was prepared using single screw
extruder.. The incorporation of al foil into HDPE increased
hardness where as decrease tensile modulus and tensile
strength of HDPE. The highest hardness of compounded was
56.8 Shore D scales at 40 wt% aluminum foil content. It was
found that increasing the aluminum foil content resulted in
very similar trend of increase in hardness properties. Because
aluminum foil is harder than matrix. The highest tensile
modulus and tensile strength of compounded was 345 MPa
and 25 MPa at 10 wt% aluminum foil content. The decreases
in the mechanical properties of HDPE with aluminum foil
were explained in associate with the presence of interface
defects between aluminum foil and polymer. SEM
micrographs indicated poor dispersion and adhesion of
HDPE/aluminum foil compounding. Furthermore, the optical
microscope results show flake structure of aluminum foil that
immiscible with HDPE. The overall results in this research
suggest that the properties of HDPE/aluminum foil composites
were influenced by aluminum foil content.
Experimental Investigation On Mechanical Properties Of Hybrid Jute Fiber Rein...dbpublications
The composite manufacturing has been a wide area of research and it is the preferred choice due to its superior properties like low density, stiffness, light weight and possesses better mechanical properties. This has found its wide applications in aerospace, automotive, marine and sporting industries. There has been continuous lookout for synthesizing composites without compromising on the mechanical and physical properties. In this project, fiber reinforced composites is preparing with jute fibers & glass fiber of fiber length 5-6 mm. The resins used in this study are epoxy. The prepared composites were tested to study the mechanical properties of the composite such as tensile strength, flexural strength, impact strength and hardness.
The document discusses various metal additive manufacturing techniques including powder bed fusion, directed energy deposition, binder jetting, and sheet lamination. Powder bed fusion techniques like selective laser melting use a laser to selectively fuse metal powder layers. Directed energy deposition techniques like laser engineered net shaping use a laser and metal powder or wire feedstock to deposit material. Binder jetting uses inkjet printing of a binder to join metal powder particles. Sheet lamination techniques like ultrasonic additive manufacturing bond metal foils using ultrasonic vibration. The document explores the process parameters, microstructures, and applications of these various metal 3D printing methods.
This document compares the amount of material waste generated between Industrialized Building System (IBS) construction and conventional construction. Through a Delphi study with 18 construction experts, it was found that IBS construction generated less waste for most materials, including bricks, cardboard, concrete, glass, plastic, roofing materials, soil/sand, tiles, and wood. The highest waste for both systems was concrete, but IBS produced less concrete waste. IBS also produced less waste for other materials except metal, which saw higher waste potentially due to metal molds used in precasting. Overall, the study shows that IBS is more sustainable and reduces construction material waste compared to conventional construction methods.
This document summarizes a research project that uses UV-assisted 3D printing to manufacture dog-bone composite samples containing carbon nanomaterials like carbon black, nanotubes, fullerenes, and graphene. The addition of 50% carbon black by weight to a clear resin improved the composite's Young's modulus by around 36% according to tensile testing results. Future work will involve more tensile, bending, and shear tests using different carbon nanomaterials and concentrations to further explore potential mechanical property enhancements of the composites. The document also provides background information on carbon nanomaterials and how UV-assisted 3D printing works.
Yu Bin has extensive experience in materials characterization, analysis, and testing. He received his bachelor's degree in materials science from Huazhong University of Science and Technology and his doctorate in engineering from Nanyang Technological University. Currently, he works as a materials engineer at ASM Pacific Technology applying his expertise in composite materials and simulation software to product design and failure analysis.
IRJET-Synthesis & Characterisation Of Epoxy Matrix Composites Filled With Alu...IRJET Journal
This document summarizes research into synthesizing and characterizing epoxy matrix composites filled with aluminum powder. Epoxy resin was mixed with 2% aluminum powder and reinforced with glass fibers using the hand lay-up process. Specimens were tested for properties including tensile strength, yield point, breaking point, impact load, and hardness. Test results showed the composite had higher strength and stiffness compared to conventional materials, making it suitable for applications requiring those properties.
The document describes a new additive manufacturing process called Composite Metal Foil Manufacturing (CMFM) that combines laminated object manufacturing and brazing to produce metal parts from metal foils. Peel and tensile tests were conducted on specimens produced from aluminum 1050 foil and copper foil using the CMFM process. The peel tests investigated the effect of peeling rate and corrosion on peel strength of aluminum foils, as well as the peel strength of aluminum/copper composites. The tensile test showed the CMFM process produced parts 8% stronger than machined aluminum. The results demonstrated the consistency and strength of parts made with the new CMFM process.
Competence and Ethical Behavior of people appointed to contract management po...Donatus Mugisha
This document summarizes a research study that examined the influence of competence on ethical behavior for staff managing contracts in local governments in Uganda. The study found that competence has a significant but moderate influence on ethical behavior, explaining 13.3-14.5% of the variation. More competent staff were somewhat more likely to behave ethically in contract management. However, other factors like social norms and individual personality traits also influence ethical behavior. The study concluded that ensuring contract managers have sufficient competence can help reduce unethical conduct, though it is not the only determining factor.
This document summarizes an article that proposes a system for compressing XML documents while still allowing queries to be efficiently evaluated on the compressed data. The system first compresses the XML document using the proposed algorithm, which divides the compressed file into different relational databases, eliminating the need to fully decompress the file for each query. Only the required information is decompressed and returned to the user. Experimental results on sample XML documents show that the system achieves competitive compression ratios compared to other query-capable XML compressors, and can efficiently answer different types of queries on multiple compressed documents with minimal decompression.
Course Objectives:
Students undergoing this course would
Understand different methods of 3D Printing.
Gain knowledge about simulation of FDM process
Estimate time and material required for manufacturing a 3D component
Course Outcomes:
Upon the successful completion of course, students will be able to
Explain different types of 3d Printing techniques
Identify parameters for powder binding and jetting process
Determine effective use of ABS material for 3D Printing
Apply principles of mathematics to evaluate the volume of material require.
Module 1:
Introduction to Prototyping, Working of 3D Printer, Types of 3D printing Machines:
Exp 1: Modelling of Engineering component and conversion of STL format.
Exp 2: Slicing of STL file and study of effect of process parameter like layer thickness,
Orientation and infill on build time using software.
Exercise 1 : Component-1
Exercise 2 : Component-2
Module 2:
Exp 1 : 3D Printing of modeled component by varying layer thickness.
Exp 2 : 3D Printing of modeled component by varying orientation.
Exp 3: 3D Printing of modeled component by varying infill.
Module 3:
Study on effect of different materials like ABS, PLA, Resin etc, and dimensional accuracy.
Module 4:
Identifying the defects in 3D Printed components.
Module 5
Exp1: Modelling of component using 3D Scanner of real life object of unknown dimension
in reverse engineering.
Exp 2: 3D Printing of above modeled component.
These documents summarize research on 3D printing technologies and their applications. Specifically, they review vat photopolymerization techniques for 3D printing polymers, the mechanical properties of 3D printed polymers and composites filled with natural fibers, defects in fused deposition modeling (FDM) 3D printing of composites and treatments to improve properties, and applications of 3D printing in medicine including creating models and implants.
Design and Development of Honeycomb Structure for Additive Manufacturingijtsrd
the demand for shorter product development time has resulted in the introduction of a new paradigm called Additive Manufacturing AM . Due to its significant advantages in terms of cost effective, lesser build time, elimination of expensive tooling, design flexibility AM is finding applications in many diverse fields of the industry today. One of the recent applications of this technology is for fabrication of cellular structures. Cellular structures are designed to have material where it is needed for specific applications. Compared to solid materials, these structures can provide high strength-to-weight ratio, good energy absorption characteristics and good thermal and acoustic insulation properties to aerospace, medical and engineering products. However, due to inclusion of too many design variables, the design process of these structures is a challenge task. Furthermore, polymer additive manufacturing techniques, such as fused deposition modeling FDM process which shows the great capability to fabricate these structures, are still facing certain process limitations in terms of support structure requirement for certain category of cellular structures. Therefore, in this research, a computer-aided design CAD based method is proposed to design and develop hexagonal honeycomb structure self-supporting periodic cellular structure for FDM process. This novel methodology is found to have potential to create honeycomb cellular structures with different volume fractions successfully without any part distortion. Once designing process is complete, mechanical and microstructure properties of these structures are characterized to investigate effect of volume fraction on compressive strength of the part. Volume fraction can be defined as the volume percentage of the solid material inside the cellular structure and it is varied in this thesis by changing the cell size and wall thickness of honeycombs. Compression strength of the honeycomb structure is observed to increase with the increase in the volume fraction and this behavior is compared with an existing Wierzbicki expression, developed for predicting compression properties. Some differences are noticed in between experimentally tested and Wierzbicki model estimated compressive strength. These differences may be attributed to layer by layer deposition strategy and the residual stress inherent to the FDM-manufacturing process. Narendra Kumar Rajak | Prof. Amit Kaimkuriya "Design and Development of Honeycomb Structure for Additive Manufacturing" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-2 | Issue-6 , October 2018, URL: http://www.ijtsrd.com/papers/ijtsrd18856.pdf
Final Report Functional Coatings for 3D Printed Parts_JONATHANAMBROSEJonathan Ambrose
This report details the development of functional coatings for 3D printed parts through two techniques: creating a uniform conductive coating and electroplating homogenously. The stages of development included multiple techniques that were tested for value, simplicity, quality of coating, cost, material properties and safety. Testing found that combining conductive coating and electroplating onto 3D printed parts successfully enhanced properties like electrical conductivity, strength and hardness from the incorporated metal coating, with increased corrosion resistance. The report provides information on the techniques researched and tested as well as recommendations for further development.
Manufacturing Processes is the title of the subject. The document outlines the teaching scheme, examination scheme, syllabus and internal assessment for the subject. The syllabus covers 6 units - casting processes, melting and molding, joining processes, conventional forming processes, advanced forming processes, and advanced manufacturing processes like rapid prototyping. Rapid prototyping involves 5 main steps - CAD modeling, CAD conversion, STL model slicing, model fabrication using techniques like stereolithography, selective laser sintering, fused deposition modeling and post-processing. It has advantages like reduced design time but also limitations such as material properties.
Multiphase jet solidification ravi ranjan pd01Ravi Ranjan
The document summarizes a presentation on multiphase jet solidification (MJS) rapid prototyping. MJS involves extruding a melted material through a jet to produce high density metallic and ceramic parts layer by layer. It works by heating a powder-binder mixture above its solidification point, then depositing it through a nozzle in layers where it solidifies. Critical parameters are nozzle speed and flow rate. MJS can 3D print using various feedstock materials like metals, ceramics and polymers to produce functional end-use parts, not just prototypes. It offers flexibility compared to traditional manufacturing and polymer injection molding.
Process control and R & D in metal additive manufacturingq-Maxim
This conference paper provides detailed understanding of process control and R & D aspects of metal additive manufacture by laser powder bed fusion (L-PBF) also called DMLS (Direct Metal Laser Sintering) / SLM process.Following process control aspects are covered : powder chemistry, powder
particle size distribution, powder morphology, powder flow properties, DMLS process control aspects, metal
physical & mechanical properties, and NDT. Applicable international standards are also listed. Paper also
briefly touches research and developmental approach for development of new materials.
This document summarizes a research article that proposes a new rapid prototyping process called composite metal foil manufacturing (CMFM). CMFM combines laminated object manufacturing and soldering techniques to produce high-quality metal parts directly from CAD models using thin metal foils and solder paste. The researchers developed an experimental setup to demonstrate CMFM and produced test specimens from copper foil. They then evaluated the specimens using lap-shear testing, peel testing, microstructural analysis, and comparison to other methods to validate the effectiveness of CMFM for producing metal prototypes.
HEALTH CENTER NEEDS MANAGER WITH GRADUATE OF PROFESSION OF PUBLIC HEALTH GENE...IAEME Publication
An additional cost of health insurance paid by the government has increased every
year. Theoretically, this is due to curative services have been more and more dominant.
The one problem might be due to different views between 2 organizations concerning
public health.
This document summarizes a research paper about modular construction in the UK healthcare sector. It examines case studies of three module manufacturers and aims to define modularity in construction, distinguish modular from traditional construction, and explore the modular design process. Key findings suggest modular construction can provide benefits like reduced time and costs compared to traditional building, though barriers like transportation constraints remain. The summary explores how the case study companies define and approach modular construction.
IRJET- Optimization of Laser Transmission Welding Process Parameters using Si...IRJET Journal
This document summarizes research on optimizing the laser transmission welding process parameters for polypropylene and polypropylene composite materials. Statistical methods like the Taguchi method and ANOVA were used to analyze how laser power, scanning speed, number of passes, and other parameters influence weld strength and width. Both single objective and multi-objective optimization techniques were applied. The optimal parameter ranges were determined to produce high quality welds without defects. SEM analysis examined the weld cross-sections and surfaces. Overall, the study investigated how to optimize the laser transmission welding process for polypropylene composites.
Study in Physical and Mechanical Properties of Renewable Aluminum Foil-Filled...prawitjitiyakron
This research studies the potential of a renewable material,
aluminum foil, as filler in high density polyethylene (HDPE).
The filler was used in range of 0-40% by weight. Aluminum
foil/HDPE compounding was prepared using single screw
extruder.. The incorporation of al foil into HDPE increased
hardness where as decrease tensile modulus and tensile
strength of HDPE. The highest hardness of compounded was
56.8 Shore D scales at 40 wt% aluminum foil content. It was
found that increasing the aluminum foil content resulted in
very similar trend of increase in hardness properties. Because
aluminum foil is harder than matrix. The highest tensile
modulus and tensile strength of compounded was 345 MPa
and 25 MPa at 10 wt% aluminum foil content. The decreases
in the mechanical properties of HDPE with aluminum foil
were explained in associate with the presence of interface
defects between aluminum foil and polymer. SEM
micrographs indicated poor dispersion and adhesion of
HDPE/aluminum foil compounding. Furthermore, the optical
microscope results show flake structure of aluminum foil that
immiscible with HDPE. The overall results in this research
suggest that the properties of HDPE/aluminum foil composites
were influenced by aluminum foil content.
Experimental Investigation On Mechanical Properties Of Hybrid Jute Fiber Rein...dbpublications
The composite manufacturing has been a wide area of research and it is the preferred choice due to its superior properties like low density, stiffness, light weight and possesses better mechanical properties. This has found its wide applications in aerospace, automotive, marine and sporting industries. There has been continuous lookout for synthesizing composites without compromising on the mechanical and physical properties. In this project, fiber reinforced composites is preparing with jute fibers & glass fiber of fiber length 5-6 mm. The resins used in this study are epoxy. The prepared composites were tested to study the mechanical properties of the composite such as tensile strength, flexural strength, impact strength and hardness.
The document discusses various metal additive manufacturing techniques including powder bed fusion, directed energy deposition, binder jetting, and sheet lamination. Powder bed fusion techniques like selective laser melting use a laser to selectively fuse metal powder layers. Directed energy deposition techniques like laser engineered net shaping use a laser and metal powder or wire feedstock to deposit material. Binder jetting uses inkjet printing of a binder to join metal powder particles. Sheet lamination techniques like ultrasonic additive manufacturing bond metal foils using ultrasonic vibration. The document explores the process parameters, microstructures, and applications of these various metal 3D printing methods.
This document compares the amount of material waste generated between Industrialized Building System (IBS) construction and conventional construction. Through a Delphi study with 18 construction experts, it was found that IBS construction generated less waste for most materials, including bricks, cardboard, concrete, glass, plastic, roofing materials, soil/sand, tiles, and wood. The highest waste for both systems was concrete, but IBS produced less concrete waste. IBS also produced less waste for other materials except metal, which saw higher waste potentially due to metal molds used in precasting. Overall, the study shows that IBS is more sustainable and reduces construction material waste compared to conventional construction methods.
This document summarizes a research project that uses UV-assisted 3D printing to manufacture dog-bone composite samples containing carbon nanomaterials like carbon black, nanotubes, fullerenes, and graphene. The addition of 50% carbon black by weight to a clear resin improved the composite's Young's modulus by around 36% according to tensile testing results. Future work will involve more tensile, bending, and shear tests using different carbon nanomaterials and concentrations to further explore potential mechanical property enhancements of the composites. The document also provides background information on carbon nanomaterials and how UV-assisted 3D printing works.
Yu Bin has extensive experience in materials characterization, analysis, and testing. He received his bachelor's degree in materials science from Huazhong University of Science and Technology and his doctorate in engineering from Nanyang Technological University. Currently, he works as a materials engineer at ASM Pacific Technology applying his expertise in composite materials and simulation software to product design and failure analysis.
IRJET-Synthesis & Characterisation Of Epoxy Matrix Composites Filled With Alu...IRJET Journal
This document summarizes research into synthesizing and characterizing epoxy matrix composites filled with aluminum powder. Epoxy resin was mixed with 2% aluminum powder and reinforced with glass fibers using the hand lay-up process. Specimens were tested for properties including tensile strength, yield point, breaking point, impact load, and hardness. Test results showed the composite had higher strength and stiffness compared to conventional materials, making it suitable for applications requiring those properties.
The document describes a new additive manufacturing process called Composite Metal Foil Manufacturing (CMFM) that combines laminated object manufacturing and brazing to produce metal parts from metal foils. Peel and tensile tests were conducted on specimens produced from aluminum 1050 foil and copper foil using the CMFM process. The peel tests investigated the effect of peeling rate and corrosion on peel strength of aluminum foils, as well as the peel strength of aluminum/copper composites. The tensile test showed the CMFM process produced parts 8% stronger than machined aluminum. The results demonstrated the consistency and strength of parts made with the new CMFM process.
Competence and Ethical Behavior of people appointed to contract management po...Donatus Mugisha
This document summarizes a research study that examined the influence of competence on ethical behavior for staff managing contracts in local governments in Uganda. The study found that competence has a significant but moderate influence on ethical behavior, explaining 13.3-14.5% of the variation. More competent staff were somewhat more likely to behave ethically in contract management. However, other factors like social norms and individual personality traits also influence ethical behavior. The study concluded that ensuring contract managers have sufficient competence can help reduce unethical conduct, though it is not the only determining factor.
This document summarizes an article that proposes a system for compressing XML documents while still allowing queries to be efficiently evaluated on the compressed data. The system first compresses the XML document using the proposed algorithm, which divides the compressed file into different relational databases, eliminating the need to fully decompress the file for each query. Only the required information is decompressed and returned to the user. Experimental results on sample XML documents show that the system achieves competitive compression ratios compared to other query-capable XML compressors, and can efficiently answer different types of queries on multiple compressed documents with minimal decompression.
Course Objectives:
Students undergoing this course would
Understand different methods of 3D Printing.
Gain knowledge about simulation of FDM process
Estimate time and material required for manufacturing a 3D component
Course Outcomes:
Upon the successful completion of course, students will be able to
Explain different types of 3d Printing techniques
Identify parameters for powder binding and jetting process
Determine effective use of ABS material for 3D Printing
Apply principles of mathematics to evaluate the volume of material require.
Module 1:
Introduction to Prototyping, Working of 3D Printer, Types of 3D printing Machines:
Exp 1: Modelling of Engineering component and conversion of STL format.
Exp 2: Slicing of STL file and study of effect of process parameter like layer thickness,
Orientation and infill on build time using software.
Exercise 1 : Component-1
Exercise 2 : Component-2
Module 2:
Exp 1 : 3D Printing of modeled component by varying layer thickness.
Exp 2 : 3D Printing of modeled component by varying orientation.
Exp 3: 3D Printing of modeled component by varying infill.
Module 3:
Study on effect of different materials like ABS, PLA, Resin etc, and dimensional accuracy.
Module 4:
Identifying the defects in 3D Printed components.
Module 5
Exp1: Modelling of component using 3D Scanner of real life object of unknown dimension
in reverse engineering.
Exp 2: 3D Printing of above modeled component.
These documents summarize research on 3D printing technologies and their applications. Specifically, they review vat photopolymerization techniques for 3D printing polymers, the mechanical properties of 3D printed polymers and composites filled with natural fibers, defects in fused deposition modeling (FDM) 3D printing of composites and treatments to improve properties, and applications of 3D printing in medicine including creating models and implants.
Design and Development of Honeycomb Structure for Additive Manufacturingijtsrd
the demand for shorter product development time has resulted in the introduction of a new paradigm called Additive Manufacturing AM . Due to its significant advantages in terms of cost effective, lesser build time, elimination of expensive tooling, design flexibility AM is finding applications in many diverse fields of the industry today. One of the recent applications of this technology is for fabrication of cellular structures. Cellular structures are designed to have material where it is needed for specific applications. Compared to solid materials, these structures can provide high strength-to-weight ratio, good energy absorption characteristics and good thermal and acoustic insulation properties to aerospace, medical and engineering products. However, due to inclusion of too many design variables, the design process of these structures is a challenge task. Furthermore, polymer additive manufacturing techniques, such as fused deposition modeling FDM process which shows the great capability to fabricate these structures, are still facing certain process limitations in terms of support structure requirement for certain category of cellular structures. Therefore, in this research, a computer-aided design CAD based method is proposed to design and develop hexagonal honeycomb structure self-supporting periodic cellular structure for FDM process. This novel methodology is found to have potential to create honeycomb cellular structures with different volume fractions successfully without any part distortion. Once designing process is complete, mechanical and microstructure properties of these structures are characterized to investigate effect of volume fraction on compressive strength of the part. Volume fraction can be defined as the volume percentage of the solid material inside the cellular structure and it is varied in this thesis by changing the cell size and wall thickness of honeycombs. Compression strength of the honeycomb structure is observed to increase with the increase in the volume fraction and this behavior is compared with an existing Wierzbicki expression, developed for predicting compression properties. Some differences are noticed in between experimentally tested and Wierzbicki model estimated compressive strength. These differences may be attributed to layer by layer deposition strategy and the residual stress inherent to the FDM-manufacturing process. Narendra Kumar Rajak | Prof. Amit Kaimkuriya "Design and Development of Honeycomb Structure for Additive Manufacturing" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-2 | Issue-6 , October 2018, URL: http://www.ijtsrd.com/papers/ijtsrd18856.pdf
Final Report Functional Coatings for 3D Printed Parts_JONATHANAMBROSEJonathan Ambrose
This report details the development of functional coatings for 3D printed parts through two techniques: creating a uniform conductive coating and electroplating homogenously. The stages of development included multiple techniques that were tested for value, simplicity, quality of coating, cost, material properties and safety. Testing found that combining conductive coating and electroplating onto 3D printed parts successfully enhanced properties like electrical conductivity, strength and hardness from the incorporated metal coating, with increased corrosion resistance. The report provides information on the techniques researched and tested as well as recommendations for further development.
Manufacturing Processes is the title of the subject. The document outlines the teaching scheme, examination scheme, syllabus and internal assessment for the subject. The syllabus covers 6 units - casting processes, melting and molding, joining processes, conventional forming processes, advanced forming processes, and advanced manufacturing processes like rapid prototyping. Rapid prototyping involves 5 main steps - CAD modeling, CAD conversion, STL model slicing, model fabrication using techniques like stereolithography, selective laser sintering, fused deposition modeling and post-processing. It has advantages like reduced design time but also limitations such as material properties.
Multiphase jet solidification ravi ranjan pd01Ravi Ranjan
The document summarizes a presentation on multiphase jet solidification (MJS) rapid prototyping. MJS involves extruding a melted material through a jet to produce high density metallic and ceramic parts layer by layer. It works by heating a powder-binder mixture above its solidification point, then depositing it through a nozzle in layers where it solidifies. Critical parameters are nozzle speed and flow rate. MJS can 3D print using various feedstock materials like metals, ceramics and polymers to produce functional end-use parts, not just prototypes. It offers flexibility compared to traditional manufacturing and polymer injection molding.
Process control and R & D in metal additive manufacturingq-Maxim
This conference paper provides detailed understanding of process control and R & D aspects of metal additive manufacture by laser powder bed fusion (L-PBF) also called DMLS (Direct Metal Laser Sintering) / SLM process.Following process control aspects are covered : powder chemistry, powder
particle size distribution, powder morphology, powder flow properties, DMLS process control aspects, metal
physical & mechanical properties, and NDT. Applicable international standards are also listed. Paper also
briefly touches research and developmental approach for development of new materials.
This document summarizes a research article that proposes a new rapid prototyping process called composite metal foil manufacturing (CMFM). CMFM combines laminated object manufacturing and soldering techniques to produce high-quality metal parts directly from CAD models using thin metal foils and solder paste. The researchers developed an experimental setup to demonstrate CMFM and produced test specimens from copper foil. They then evaluated the specimens using lap-shear testing, peel testing, microstructural analysis, and comparison to other methods to validate the effectiveness of CMFM for producing metal prototypes.
This document is a seminar report on laser beam welding of plastics submitted by Deepa Ram. The report provides an overview of laser plastic welding, including the fundamentals of the process, common laser sources used, welding of similar and dissimilar plastics, advantages, applications in automotive and electronics industries, and quality control methods. It also discusses hybrid laser welding technologies and fiber laser welding assisted by a solid heat sink. The report was submitted in fulfillment of course requirements and provides a comprehensive review of the topic of laser plastic welding.
Graphene-based 3D printed circuit boardIRJET Journal
This document discusses using graphene to create 3D printed circuit boards via additive manufacturing. It begins with background on additive manufacturing and how it differs from traditional manufacturing methods. The authors propose using graphene ink for 3D printing due to graphene's high electrical conductivity and strength. The objectives are to extract graphene, create a homogeneous graphene ink, and develop an attachment for existing 3D printers to enable graphene-based 3D printing. The document reviews the evolution of additive manufacturing technologies and materials.
Experimental Investigation on Interlayer Bonding Strength of 3D Printed Concr...IRJET Journal
This document summarizes a literature review on 3D printed concrete. It discusses the objectives of studying interlayer bonding strength in 3D printed concrete structures and reducing alkali-silica reaction (ASR). The literature review covers topics like the effect of time gaps between printed layers on bonding strength, modeling fresh self-consolidating concrete flow, and using recycled sand in 3D printed concrete mixes. It also examines prior research on predicting concrete properties with artificial neural networks, improving buildability and early strength with nanoclay additives, and using viscosity modifying admixtures like polyacrylamide and polyvinyl alcohol fibers in printable concrete mixes.
This document summarizes recent simulations of cold forming processes using the DEFORMTM-3D software. It describes three case studies: 1) the coining of a heat sink with self-contacting surfaces, 2) the assembly of a nut and plate with mesh-to-mesh contact, and 3) the extrusion of a helical gear using rotational symmetry. It also discusses simulations of thread rolling and stress analysis of the threading dies. The case studies demonstrate capabilities for modeling multiple deforming objects, self-contact, and large rotational problems. Finite element simulation has become an integral part of process design in metal forming industries.
This document summarizes recent simulations of cold forming processes using the DEFORMTM-3D software. It describes three case studies: 1) the coining of a heat sink with self-contacting surfaces, 2) the assembly of a nut and plate with mesh-to-mesh contact, and 3) the extrusion of a helical gear using rotational symmetry. It also discusses simulations of thread rolling and stress analysis of the threading dies. The case studies demonstrate capabilities for modeling multiple deforming objects, self-contact, and large rotational problems. Finite element simulation has become an integral part of process design in metal forming industries.
This document discusses fused deposition modeling (FDM), a type of additive manufacturing. FDM uses thermoplastic filament fed through an extruder head to deposit material layer by layer. The heated extruder head melts the filament and deposits it in thin layers on a platform according to a 3D computer model. Each new layer bonds to the previous layer, allowing three-dimensional objects to be built up from successive layers of material. FDM is a low-cost type of 3D printing that works well for prototypes and some end-use parts using thermoplastics like ABS and PLA. The document provides details on the FDM printing process and compares it to other additive manufacturing techniques.
IRJET- 3D-Printing in Additive ManufacturingIRJET Journal
This document summarizes research on 3D printing and additive manufacturing techniques for polymers. It discusses several common 3D printing methods like fused deposition modeling, stereolithography, digital light processing, selective laser sintering, three-dimensional printing, laminated object manufacturing, and PolyJet technology. It also reviews studies evaluating the mechanical properties of 3D printed parts under different loading conditions and the effects of fillers and post-processing on mechanical properties. The goal is to understand the strengths of 3D printed parts for practical applications and facilitate standardization of mechanical testing methods.
This review article summarizes recent trends in additive manufacturing materials and processing issues over the last two decades. It provides an overview of various additive manufacturing material categories including plastics, metals, ceramics, composites and smart materials. The suitability of different materials for additive manufacturing techniques is discussed. Issues related to materials processing and different binding mechanisms are also reviewed. The future outlook of additive manufacturing materials research is focused on addressing remaining challenges.
The document discusses how 3D printing could be used in the electronics industry to manufacture products. It outlines how 3D printing allows electronics to be placed directly inside 3D designed housings rather than having housings built around 2D circuit boards. Direct printing of interconnects using techniques like laser-induced forward transfer could replace traditional circuit board manufacturing and assembly. This would reduce costs by eliminating board production and assembly steps. It could also allow components to be placed first and then printed interconnects, simplifying manufacturing and reducing use of solder paste. The document examines the technical capabilities needed for 3D printed electronics and notes research is ongoing to advance these techniques.
3D printing & its application in pharmaceutical industry.pptxJitulAdhikary1
3D printing offers several advantages for pharmaceutical applications, including customized and personalized medicines through flexible fabrication of medical equipment and drug products. Some key pharmaceutical applications of 3D printing include 3D printed implants for controlled long-term drug delivery, and 3D printed tablets which allow customized dosing and formulations. 3D printing technologies like powder bed fusion, material extrusion, and vat photopolymerization are being used to produce these drug products and expand opportunities for personalized medicine.
CHARACTERIZATION AND ANALYSIS OF MECHANICAL PROPERTIES FOR 3D PRINTING MATERIALSIRJET Journal
This document analyzes and compares the mechanical properties of common 3D printing materials like polylactic acid (PLA) and Lay Wood. It first reviews previous literature that has studied properties like tensile strength, elastic modulus, impact strength and crystallinity of 3D printed PLA under different conditions. It then describes conducting tensile, compressive and hardness tests on PLA and Lay Wood specimens printed using a Creality 10-S 3D printer. The results of these tests are presented in tables showing the mechanical properties of each material.
Advanced Additive Manufacturing by Sumanth A.pptxSumanth A
Advanced additive manufacturing, also known as advanced 3D printing,
refers to a set of advanced techniques and technologies that go beyond traditional
3D printing methods. It incorporates new materials, designs, and technologies that
allow for greater customization, complexity, and efficiency in the production of
three-dimensional objects.
Similar to Laser based mid manufacturing processes and qualification methods regarding their metallization (20)
Advanced control scheme of doubly fed induction generator for wind turbine us...IJECEIAES
This paper describes a speed control device for generating electrical energy on an electricity network based on the doubly fed induction generator (DFIG) used for wind power conversion systems. At first, a double-fed induction generator model was constructed. A control law is formulated to govern the flow of energy between the stator of a DFIG and the energy network using three types of controllers: proportional integral (PI), sliding mode controller (SMC) and second order sliding mode controller (SOSMC). Their different results in terms of power reference tracking, reaction to unexpected speed fluctuations, sensitivity to perturbations, and resilience against machine parameter alterations are compared. MATLAB/Simulink was used to conduct the simulations for the preceding study. Multiple simulations have shown very satisfying results, and the investigations demonstrate the efficacy and power-enhancing capabilities of the suggested control system.
Adaptive synchronous sliding control for a robot manipulator based on neural ...IJECEIAES
Robot manipulators have become important equipment in production lines, medical fields, and transportation. Improving the quality of trajectory tracking for
robot hands is always an attractive topic in the research community. This is a
challenging problem because robot manipulators are complex nonlinear systems
and are often subject to fluctuations in loads and external disturbances. This
article proposes an adaptive synchronous sliding control scheme to improve trajectory tracking performance for a robot manipulator. The proposed controller
ensures that the positions of the joints track the desired trajectory, synchronize
the errors, and significantly reduces chattering. First, the synchronous tracking
errors and synchronous sliding surfaces are presented. Second, the synchronous
tracking error dynamics are determined. Third, a robust adaptive control law is
designed,the unknown components of the model are estimated online by the neural network, and the parameters of the switching elements are selected by fuzzy
logic. The built algorithm ensures that the tracking and approximation errors
are ultimately uniformly bounded (UUB). Finally, the effectiveness of the constructed algorithm is demonstrated through simulation and experimental results.
Simulation and experimental results show that the proposed controller is effective with small synchronous tracking errors, and the chattering phenomenon is
significantly reduced.
Hierarchical Digital Twin of a Naval Power SystemKerry Sado
A hierarchical digital twin of a Naval DC power system has been developed and experimentally verified. Similar to other state-of-the-art digital twins, this technology creates a digital replica of the physical system executed in real-time or faster, which can modify hardware controls. However, its advantage stems from distributing computational efforts by utilizing a hierarchical structure composed of lower-level digital twin blocks and a higher-level system digital twin. Each digital twin block is associated with a physical subsystem of the hardware and communicates with a singular system digital twin, which creates a system-level response. By extracting information from each level of the hierarchy, power system controls of the hardware were reconfigured autonomously. This hierarchical digital twin development offers several advantages over other digital twins, particularly in the field of naval power systems. The hierarchical structure allows for greater computational efficiency and scalability while the ability to autonomously reconfigure hardware controls offers increased flexibility and responsiveness. The hierarchical decomposition and models utilized were well aligned with the physical twin, as indicated by the maximum deviations between the developed digital twin hierarchy and the hardware.
Literature Review Basics and Understanding Reference Management.pptxDr Ramhari Poudyal
Three-day training on academic research focuses on analytical tools at United Technical College, supported by the University Grant Commission, Nepal. 24-26 May 2024
Low power architecture of logic gates using adiabatic techniquesnooriasukmaningtyas
The growing significance of portable systems to limit power consumption in ultra-large-scale-integration chips of very high density, has recently led to rapid and inventive progresses in low-power design. The most effective technique is adiabatic logic circuit design in energy-efficient hardware. This paper presents two adiabatic approaches for the design of low power circuits, modified positive feedback adiabatic logic (modified PFAL) and the other is direct current diode based positive feedback adiabatic logic (DC-DB PFAL). Logic gates are the preliminary components in any digital circuit design. By improving the performance of basic gates, one can improvise the whole system performance. In this paper proposed circuit design of the low power architecture of OR/NOR, AND/NAND, and XOR/XNOR gates are presented using the said approaches and their results are analyzed for powerdissipation, delay, power-delay-product and rise time and compared with the other adiabatic techniques along with the conventional complementary metal oxide semiconductor (CMOS) designs reported in the literature. It has been found that the designs with DC-DB PFAL technique outperform with the percentage improvement of 65% for NOR gate and 7% for NAND gate and 34% for XNOR gate over the modified PFAL techniques at 10 MHz respectively.
Laser based mid manufacturing processes and qualification methods regarding their metallization
1. Laser Based MID Manufacturing Processes and Qualification
Methods Regarding Their Metallization
Jamshed Karim Babu and Andreas Brose
Otto-von-Guericke University of Magdeburg
Institute for Micro and Sensor System
Universitätsplatz 2, 39106 Magdeburg
jamshed.babu@st.ovgu.de
Abstract— Molded Interconnect Device (MID) has added a
new dimension to different engineering sectors which is in constant
need of improvement in functionality, integration density and
miniaturization. Due to their versatile possibilities for functional
integration and spatial design freedom, MID offers a reasonable
solution and limitless possibilities. The fields of application of MID
is increasing day by day and it is frequently being used in crucial
fields like safety and security relevant systems where reliability is
an important issue. This reliability issue is highly influenced by the
adhesion strength of the MID. However, there are no general
standards or guidelines that can test or evaluate the Molded
Interconnect Devices. To determine the adhesion strength of the
metallization on the Molded Interconnect Devices a limited
number of effective and suitable test methods are available. In this
paper, firstly laser-based MID structuring processes are described
keeping the focus on LDS process. In addition, suitable LDS
parameters for metallization, importance of adhesion and
frequently used test methods to determine the Adhesion strength
are presented along with their assessment regarding their
suitability in different cases along with focusing on the suitability
of Laser Direct Structuring process among the available MID
structuring processes. Additionally, new hot pin pull test is
described in detail. The importance of testing standards is
illustrated by the impact of influencing factors on the test results,
such as the wetting of the test structures with solder and the
temperature. Finally, the results of the comparative investigations
has been described which show promising conclusion concerning
a low standard deviation and reproducibility.
Keywords—Adhesion, Molded Interconnect Device, Adhesion
Strength Test, Hot Pin Pull Test, Peel Test, Shear Test, Laser Direct
Structuring.
I. INTRODUCTION
3-Dimensional Molded Interconnect Devices are a fast
emerging technology. It combines traditional injection molding
of plastic products with 3-dimensional conductor pattern
generation through selective metallization of the surface for
electrical or electronic circuit interconnection. On a more formal
definition, the Molded Interconnect Device (MID) is injection
moulded (plastic) part with electrically conductive circuit paths
or interconnects on the surface of the substrate. Through this
specific technology, electrical and mechanical functions are
integrated into the same component which enables the product
size, complexity and manufacturing process to be significantly
reduced. By this technology we are provided with an electro-
mechanical method of interconnecting electronic circuitry
through precise integration of connection media, such as holes,
connectors and tracks. Increased design flexibility, high volume
of production capabilities, reduced component inventory and
reliable process control e.g. use of MID in flow sensor, OLED,
multiband antennas for smartphone, ACC position sensor,
pressure sensor, insulin pump, 3D switching module, solar
sensor - these benefits are offered as a result of injection molding
of plastic parts. Again, like injection molding, metallization of
plastic by means of chemical deposition technique is a mature
technology. By combining both of the technologies and
introducing two or three dimensional conductive patterns, MID
manufacturing on a volume scale has been enabled in successful
manner.
The manufacturing processes for MID are many and varied.
Mainly the process which will be selected depends on the basis
of stated criteria. Laser structuring (additive and subtractive),
two-shot molding, hot embossing and film insert molding are the
most important processes. Plasma structuring and printing
technologies are also making their mark and being valued
gradually.
Fig. 1: Reference process steps for MID [1].
There are other minor significant technologies for now such as
masking and primer technology and physical processes of
metallization. Needless to say, all of these processes are oriented
towards the reference process of higher order MID shown in Fig.
1. The production of the MID blank which is a three-step
process, is followed up by various connection techniques to
complete the whole procedure. Soldering, conductive-adhesion
bonding, wire bonding and press fitting are the primary
connection techniques. As Fig. 1 depicts, apart from the basic
structuring processes, other structuring processes like Primer
Technology, Tampon Printing and Plasma Technology are also
used. While applying one-shot injection molding, depending on
the necessity and suitability of the situation one can go for LPKF
Laser Direct Structuring Process, ADDIMID Technology or
other alternative laser structuring processes and choose different
printing techniques such as Aerosol Jet Printing, Inkjet Printing
or Hot Embossing. Similarly a lot of options are available while
2. following the Film Insert Molding structuring. One can choose
from Thermoplastic Foam Molding, Injection Compression
Molding, Press Insert Molding or other varieties of Film Insert
Molding. From selecting proper thermoplastics to executing all
the processes in between, a number of key factors play an
important role that decide the quality of the final outcome in the
procedure. In this paper, different laser-based MID structuring
techniques are briefly discussed along with an enhanced
description of LDS process. Later on different LDS parameters
are discussed for creating fine pitch metallization. And lastly
various existing adhesion strength measuring tests including the
hot pin pull test were discussed and compared to highlight their
usefulness and effectiveness.
II. LASER-BASED DIFFERENT STRUCTURING
TECHNIQUES
Specifically when it comes to laser structuring, various
techniques are commonly classified as additive, semi-additive or
subtractive technique. Laser direct structuring is an additive
technique and the most important manifestations are LPKF-
LDS® and ADDIMID. Among the semi-additive techniques
MIPTEC, a process developed by Panasonic is mention-worthy.
On ceramic substrate materials subtractive laser structuring
techniques are applied commonly. A general overview of the
process steps is shown in Fig. 2.
Additive Semi-additive Subtractive
Fig. 2: Process steps in additive, semi-additive and subtractive structuring [1].
II(a). LPKF-LDS® PROCESS
More than 50% of the market is accounted by the Laser
Direct Structuring (LDS) process when it comes to structuring
MID [1]. It has become vastly popular in MID production over
the last decade due to various reasons such as offering high level
of versatility, possibilities for prototyping, series production,
low tool costs, micro-fine structures and high 3D design
freedom. In addition to that it is now being possible that a wide
range of thermoplastics can be used in this structuring technique
which widens its reach even more. As the development and
diversity regarding color and type of plastic, materials has been
increasing enormously over recent years, the LDS process holds
limitless possibilities. The following section contains a brief
overview of currently popular materials and overall process
steps of LDS.
LDS Substrates: Different types of plastics are available for
their application varieties and corresponding sets of
requirements. The selection may range from run-of-the mill
plastics such as ABS (Acrylonitrile Butadiene Styrene) through
high-specification polyamides to high-temperature plastics such
as LCP (Liquid Crystal Polymer) and PEEK (Polyether Ether
Ketone). According to the properties of the material the price
range also varies from one to another. However, due to excessive
demand in telecommunication sectors and comparatively
cheaper price, PC (Polycarbonate) and ABS are the most
commonly used material. There is also a very wide range of
plastic materials available for the LPKF-LDS® process. In most
of the cases, the plastics which are suitable for laser direct
structuring require a specific additive that is added to the blend
during compounding. The compounding is made possible by the
extreme heat resistance of this additive which also prevents
nucleation in the injection-molding process. It affects specific
properties of the plastics by only a little margin. There are
chemical substances in the additive which gets activated by the
laser irradiation and also gets exposed by ablation of the molding
skin. To prepare plastics for laser direct structuring without the
specific LDS additive, a product akin to an LDS painting system
is made available by LPKF [1]. A two-component primer/curing
agent system named ProtoPaint LDS is used for coating plastic
injection moldings with an LDS-compatible skin. In general, the
agents which can be applied to improve the adhesion are called
primers. In MID technology, materials with paint-like properties
are called primers and curing agents are those materials which
helps to separate liquid carriers from metallic constituents.
Application procedure is followed by standard spray gun or
spray coating technique where in both the cases a coat
approximately of 30 to 40 µm thickness has to be applied in two
steps and then cured. Then the plastic parts can be structured.
The results can also be comparable to those achieved with LDS
plastics. However, this process is only applied primarily for
prototyping as the constant-use properties are not comparable
with those of plastics with LDS additive in the compound.
Major Steps of LPKF-LDS® Process: The major four steps of
LPKF-LDS® method are: Injection molding, laser structuring of
the plastic, metallization and surface finishing shown in Fig. 3.
Plastics which get compounded with the LDS additive are fully
compatible with the injection-molding process. The principle of
ablation and nucleation by laser irradiation mostly determines
the basis of Laser Direct Structuring. According to [1], for the
patterning Nd:YAG laser, about 1 to 2 µm of material from the
surface gets ablated while simultaneously activating the additive
necessary for metallization creating a microscopically rough
Mold plastic body
Laser-structure
plastic
Surface finishing
Chemical copper
Mold plastic body
Surface activation
Chemical copper
Apply photoresist
Laser structuring
of photoresist
Galvanic copper
and surface
finishing
Etch away photoresist
and metallization
Mold plastic body
Surface activation
Chemical copper
Electrolytic
copper
Galvanically build
etch resist
Laser structuring
of etch resist
Etch away copper
Surface finishing
3. surface. This surface contains nuclei embedded in the micro-
cavities produced by the laser which creates an adhesion bond
between the plastic and the metallized layer without any need
for additional post-ablation treatment. These nuclei are
catalytically active as well. At this time processing rates can get
as high as 4000 mm/s which can be constantly diminishing with
increasing three-dimensionality and the complexity of part. This
happens because of the limitation of scanning speed for focus
tracking in Z axis. The more wide the angle to the target surface,
the more rapidly the focus has to be adjusted. After the laser
structuring of the substrate, metallization is done with Cu-Ni-Au
buildup. Metallization step is generally followed by couple of
extra cleaning steps which are necessary for activation, pre-
treatment and coating. After this, surface finishing is done which
makes the MID ready to go through the necessary assembly
procedures.
Fig. 3: Process steps provided by LPKF
LDS is environmentally friendly because components are easy
to sort for recycling as no etching or pickling chemicals are
required. It offers high level of functionality and low
construction volume.
II(b). ADDIMID PROCESS
Another additive laser structuring technique is ADDIMID.
It can be applied to stereo-lithographic structure components or
injection-molded plastic bodies. It bears a similar resemblance
not only in the process chains but also in modification of a
plastic by the addition of special fillers with the LPKF-LDS®
process [1]. This particular technology involves upgrading the
plastic with an additive consisting of a metal powder with an
electrically insulating cladding material. This technology is still
under development. In trials, microfine materials Cu, Ni and Al
powders with particle diameter from range of 0.5 to 1.2 µm
have been used up to date [1]. Being similar to the LPKF-LDS®
technique, in ADDIMID technique also after the raw material
has been compounded the plastic bodies are injection-molded.
In this process just like LDS technique a Nd:YAG laser with a
wavelength of 1064 nm gets used for structuring [1]. For this
purpose a 𝐶𝑂2 laser with 10.6 µm wavelength can also be used.
As a crucial process advantage both methods exploit the duality
of lasering. While the surface for structuring is partially ablated,
the fillers which are mixed through the plastic matrix gets
activated which subsequently act as the catalyst for chemical
metallization. This technique offers high flexibility, suitability
for prototyping along with series production, high 3d design
freedom and also low tooling costs. From economical point of
view it also offers the advantage of low material costs for the
additive. Regarding the structure widths of conductor traces and
spacing, nothing specific can be said as the research is still
ongoing [1].
II(c). MIPTEC PROCESS
In terms of process chains, Panasonic’s semi-additive
MIPTEC (Microscopic Integrated Processing Technology)
technique of structuring differs widely from the LPKF-LDS®
and ADDIMID. As shown in Fig. 2, after injection-molding of
the plastic body, copper plating is required [1]. After that
removal of unwanted metal is done by UV or IR lasering
followed by galvanic reinforcement of copper layers. Finally,
the etching of unwanted copper is done and the body gets ready
for surface finishing. Multiple parts are produced in a single
sheet and are then diced. Removal of the metallization takes
place in this technique meaning that with inter-conductor
spacing of the same order, very fine conductor structures of 50
µm can be produced using this process. This happens because
after the full-coverage plating, the laser structuring takes place
and a very high quality surface with very low roughness are
produced by metallization. As a result, without any post-
working steps semiconductor chips can be bonded. However,
the only materials currently compatible with the MIPTEC
process are PPA as a thermoplastic substrate and the two
ceramics AI203 and AIN. But new scopes regarding the
ceramics are opening up as with very good thermal conductivity
and minimal thermally induced expansion, ceramics have a
crucial advantage for MID LED applications in particular.
II(d). LSS PROCESS
LSS (Laser Subtractive Structuring) process has more steps
than additive or semi-additive processes (Fig. 2). After
injection-molding step, short surface activation takes place to
permit electroless copper or nickel plating. This is a chemical
pre-metallization which is then followed by a galvanic process
to build up the plating to target thickness. By application of an
activable etch resist which can be of photoresist or galvanoresist
type, the structuring takes place. Galvanoresists are removed by
laser energy whole photoresists react chemically to UV energy.
Photoresists can be further categorized as positive or negative.
After exposure, positive photoresist is soluble and it washes off.
On the other hand, solubility of the negative photoresist
decreases after the exposure. With a conductor width of 30 µm,
resist technology can be used to produce structures at a
patterning speed up to 2000 mm/s [1]. Breakage of the resist at
the edges of the structures can occur after the post-exposure
processes, which may result in high fluctuations in the width of
the insulating channels between the tracks. Another problem is
the presence of contaminants in the resist as a single grain of
dust is enough to prevent activation of resist it shadows.
Incomplete insulation results in shorting as a possible fault.
Galvanoresists can be a good alternative to avoid these
problems but it limits the patterning speed to 600 mm/s [1].
Higher patterning speed relates to major risk of incomplete
ablation of the resist with the resulting fault of shorting. Post-
working of areas which are not ablated is possible in principle,
but it adds further steps making the process complicated.
Another alternative procedure is repeated exposure of the same
areas at a higher throughput rate, which is a trade-off between
higher speed and the extra time needed for the repeat passes.
4. Chemical or electrochemical finishing of the parts can also be
an alternative, but this too adds complicated steps to the
process. LSS process is particularly efficient in providing 3D
injection molding parts with extensive strip conductors. Major
drawbacks of the subtractive technique are the extensiveness
and complexity in the process chain and the severe fluctuations
in the thickness of the plating.
After the overall structuring process is done different
suitable printing process is required to print the desired layout
which is followed by the metallization step. Once the
metallization takes place, assembly of the components is
required. Finishing all these steps properly, the reliability and
quality of the final MID product gets tested which is done by
different conventional test methods.
III. OPTIMIZED LDS PROCESS PARAMETERS FOR
CREATING FINE PITCH METALLIZATION
When it comes to high accuracy, Laser Direct Structuring
process has already gained quite a good reputation. Very
recently some experimental tests were carried out according to
[2] in order to study and observe the effect of the LDS
parameters on the dimensions of the micro groove. According
to [2], in the experimental work a polymer plate having
dimensions of 60x60x2 mm have been used. The material is
VESTAMID® HT plus LDS 3031 black. It is a mineral
reinforced Polyphthalamide (PPA) with glass fiber. According
to LPKF-LDS technology, this compound is designed to be
used in the production work of 3D MID. To perform the tests a
laser machine Nd:YAG laser having 1064 nm wavelength,
beam diameter of 65 µm, power in the range from 1 to 17 W,
maximum frequency 200 kHz and maximum pulse duration
23.7 ns was used. Several important parameters of LDS process
like laser power, laser scan speed, laser frequency and the width
space between the two circuit lines are studied and different
tests were performed to observe the actual effect on the MID.
The quality of the MID depends hugely upon the LDS
structuring and metallization step and the dimensions and the
profile of the laser groove plays a very important role to
determine and ensure the desired quality. It is mention-worthy
that for each and specific LDS parameters there is a different
groove dimension and profile. For achieving best groove
dimensions and profile suitable optimum laser parameters must
be obtained. 3D laser microscope scan at the surface of the
polymer has been shown in Figure 4(a) and Figure 4(b) depicts
the cross sectional area of the groove.
Fig. 4(a): 3D laser scan image of the groove profile [2].
Fig. 4(b): Important groove dimensions [2].
Fig. 4(c): Metallization thickness.
Fig. 4(c) shows the metallization thickness in the different zone,
the maximum being at the center and the minimum at the edge.
But interesting fact is that the above behavior between the
groove and metallization profile changes after two lines are
created together maintaining a specific distance between them.
And this change occurs due to heat interaction between the
grooves of the two lines, which may produce defects between
the created circuit lines depending on their distance values. A
very important relationship appeared to be present between the
minimum distance achieved between the two circuit lines and
the interactive zone width. To calculate the interactive zone
width (I.Z.W.), the minimum space (Ms) or distance between
two circuit lines and the proposal distance (Ps) of the two
grooves an equation has been proposed-
Ms = Ps – I.Z.W. (1)
During the LDS process when there is no interaction between
the heat transfers for the two grooves, equation 1 can be used.
Normally when the proposal distance (Ps) is high enough, this
effect does not occur. But whenever it requires low Ps, such as
micro MID products, it is a serious problem. By changing the
sequence of the laser structuring for the circuit lines to give
enough time for cooling and thus preventing the heat interaction
between the grooves, this effect can be reduced to a minimum
amount. To avoid metallization defect, it is very important to
use specific types of LDS parameters to produce one width of
the circuit lines. LDS parameters including laser power of 12
W, laser speed of 1000 mm/s and laser frequency of 70 kHz can
be used for the interior area of the circuit line as shown in Fig.
5. At the boundary of the circuit line another set of parameter
can be used including, laser power in range from 3 to 9 W, laser
speed of 2200 mm/s and laser frequency in range from 110 to
130 kHz [2]. These parameters were tested and under these
parameters metallization defect will not occur.
Half width of the interactive zone
Metallizationthickness
5. Fig. 5: The metallization process for, (a) Defect, laser power of 12 W, laser
speed of 1000 mm/s and laser frequency of 70 kHz, and (b) No defect, laser
power of 9 W, laser speed of 2200 mm/s and frequency of 90 kHz [2].
According to [2], the minimum distance (Ms) always increases
with the laser speed and decreases with the laser power. Also
Ms increases with the laser frequency. Depending on the value
of Ms, laser diameter D and minimum space distance of
metallization process (MSM), the value of Ps can be readjusted.
Mainly depending on two conditions the value of Ps can be
changed accordingly.
First: Ms – D > MSM
In this case, metallization defect will not occur. Also the value
of Ps can be reduced to the value equal to or more than the
laser beam diameter (D). So 𝑃𝑠 𝑛𝑒𝑤 = Ps – D
Second: Ms – D ≤ MSM
Metallization defect will occur in this case and the Ps value
cannot be reduced. So 𝑃𝑠 𝑛𝑒𝑤 = Ps
IV. IMPORTANCE OF ADHESION
Before moving on to different test methods to measure the
adhesion strength of MID, the influence and importance of
adhesion should be emphasized properly as one of the key
performance indicators in MID technology is the adhesion of
the metallization with the thermoplastic substrate. The
mechanical stability of the conductors and the components on
the carrier both depend on the strength of the bond between
metallization and the substrate. Adhesion is the bond between
metallization and the substrate whereas cohesion is the inner
strength of the adhesive.
Fig. 6: Cross section of a bond [4].
The adhesive stays in its normal state in the cohesion zone
whereas in the adhesion zone the adhesive has a modified
structure and composition due to its adhesion to the surface of
the substrates. In the adhesion zone the molecular interaction
between the substrate surface and adhesive takes place altering
the macroscopic properties of the adhesive in the adhesion zone.
In the transition zone between the adhesion zone and the
cohesion zone the structure, composition and macroscopic
properties of adhesive continuously changes. The adhesion
strength tests discussed below are of destructive type. These
tests are performed for qualification during the development
phase of the MID and maybe randomly during serial production
of parts which cannot be sold afterwards. Formation of strong
adhesion bond forces between molecules and an optimal wetting
behavior are very important in order to maintain the bonding
strength between metallization and the plastic substrate.
Fig. 7 (a): Creating micro-rough surface [4].
Fig. 7 (b): Adhesion bond between metallization and substrate [4].
Fig. 7 (c): Actual illustration of metallization on plastic substrate [4].
Adhesive
Substrate
Adhesion
zone
Substrate
Transition
zone
Cohesion
zone
Adhesion
zone
6. The most important factor that plays a key role in forming the
adhesion bond is the macromolecular construction and the
surface energy of polymer [3]. The polarities of the molecule
surface structure caused by dipole, dispersion forces or
ancillary valence, considerably affect the strength of the
adhesion bond. The enrichment of the polar groups of polymer
which can be achieved physically or chemically ensures
improved adhesion bonding between metallization and the
substrate. As mentioned earlier, while laser-activating the
substrate a micro-rough surface (Fig. 7) is created with nuclei
in it. During the metallization process Copper (Cu) is deposited
to this nuclei in plastic substrate and metallization gets firmly
mechanically anchored by the adhesion bond.
As metallization is considered the most critical step of MID
manufacturing process, adhesion bond between metallization
and polymer substrate is one of the most important factor of this
step. Adhesion bond plays an important role and contributes
deeply as it holds the metallization against the ultra-sonic power
in wire bonding, compensates thermo-mechanical stress caused
by manufacturing processes like soldering or curing and by
environmental conditions during product lifetime, creates
stability during reliability testing in the electrical connection [4].
However, different types of defects (Fig. 8) can already occur
due to the metallization which has a valuable impact on the
adhesion bonding afterwards [4]. The bond strength needs to be
in such a reliable manner that the whole device can withstand
the thermo-mechanical and mechanical loads. However, the
real challenge is determining the Adhesion strength of the bond
between the plastic substrate and the thin layers of metal.
Fig. 8: Different types of defects in Metallization of MID [4].
The structure sizes involved and the three-dimensional layout
of the MID contributes to a certain proportion to hamper the
reproducibility of adhesion tests, which is why practicality of
testing needs to be considered. One good feature of a reliable
mechatronic system is that it presupposes an adhesion bonding
of the conductor tracks on the substrate. Especially when it
comes to MID, the quality gets significantly determined by the
adhesion strength of the metallization to the substrate.
Numerous factors along the entire manufacturing chain
influence the initial adhesion strength of the MID. The adhesion
of the metallization can be significantly affected by the decision
in each process step. Thus it can influence factors like selection
of the substrate material through the design of the molding tool,
different parameters of the injection molding tool, chemistry
used for cleaning, structuring and metallization. All the
processes that come one after another such as reflow soldering,
transmission of pins by press-fit technology or wire bonding do
require a sufficient adhesion strength which depends on the
individual process and hence, further influences the initial
adhesion. Moreover in rough environmental conditions, the
adhesion strength decreases during product lifetime due to
thermal and mechanical loads as well as by chemical and
climatic influences. So, this issues also need to be taken into
account. For MID, during laser structuring or etching, a micro-
rough surface is accomplished on the basis of which mainly the
bonding mechanism between metallization and substrate
depends on. With different polymer and different laser
parameters the roughness can change. Layers with a typical
thickness of 5-15 μm copper, 5-15 μm nickel and 0.1 μm gold
are build up. And one of the toughest challenges during the
processing step is to determine the adhesion strength of these
thin metallized layers on thermoplastic substrate. To determine
the adhesion strength of MID, different conventional test
methods are applied which are mainly adopted from the existing
testing standards from PCB technology e.g. pull-off/pull out
test, peel test, tape test, shear force measurement test.
V. CONVENTIONAL TEST METHODS
Most commonly used methods which are applied to
determine the adhesion strength of MID are known as Shear
Force Measurement, Pull-off Test and Peel Test. As the test
methods differ considerably from one another in their procedure
and set-up, a direct comparison is not possible among them. The
type of failure modes also differ from each other because the
type of loading applied in order to determine the adhesion also
varies. These three methods are described below along with their
specific criteria and applicability on MID.
Pull-off Test: A very well-known method used to determine the
adhesion strength, mostly of thin surface coating is the pull-off
test [5]. Tensile forces act vertically on the test area in this test
procedure and those particular forces are measured. A dolly
needs to be soldered or glued to the composite panel to perform
this test. Once the prepared specimen is fixed in the device
which is being tested, an increasing amount of tensile force
applied to the dolly until the coating detaches from the substrate
as shown in Fig. 9.
Fig. 9: Schematic illustration of Pull-off test [5].
7. Finally, from the size of the detached area and the maximum
force applied to the dolly, the Adhesion strength of the bond is
calculated.
In case of other failures occurring elsewhere than between the
desired substrate and metallization, it is very much necessary to
add a reference to the fracture pattern as a supplement to the
original measured value. As MID technology differs a lot from
the conventional PCB technology due to its spatial design
freedom, a test dolly (diameter 7 mm) is recommended for
testing adhesion from one side only [2].
Fig. 10: Different failures during unsuccessful Pull-off test [5]
Due to lack of having large and planar surfaces on MID, the
continuous change in size for dolly and test structure has to be
considered as well. As a result, the positioning of the dolly and
the manual application of the adhesions become significantly
difficult which can eventually result in an increased standard
deviation. In Fig. 10, too less adhesion was applied in section 1,
excessive amount of adhesion was used in section 2 and the
position of the dolly was decentralized on the test structure in
section 3, as all of these are the results of failures performing
pull-off test on MID.
Advantage:
Easy procedure.
Standard tensile test equipment can be used.
Disadvantage:
Large test pad (at least of ø 7 mm).
High temperature impact due to soldering process if the
dolly is soldered, not glued.
Influence by manual handling.
Peel Test: To determine the adhesion strength of conductor
tracks on printed circuit boards another common test method is
used named peel test. In order to perform the test, a pull-off
object is needed to be affixed to the conductor track by gluing,
soldering or clamping and by peeling the conductor tracks off
the substrate the adhesion strength is determined. At a constant
speed of 50±5 mm/min. a steadily increasing tensile force is
applied orthogonally to the conductor track in order to peel off
the conductor as shown in Fig. 11. For ensuring the constant
peeling angle the substrate is moved contrary to the direction of
peeling. As the peel-off force is the lowest force measured per
conductor, the adhesion strength can be calculated as quotient of
the minimum force measured and the width of the conductor
track. A conductor track with a width of 3±0.2 mm, a thickness
of at least 35 µm and a length of 65 mm are recommended in
order to perform the peel test [5]. As this requirement of
conductor tracks usually do not meet with the conductor tracks
on MID, the peel test is only used in exceptional cases for testing
MID.
Fig. 11: Schematic illustration of Peel test [5]
Common MID would need a galvanic reinforcement to meet the
necessary requirement of the thickness to perform usual peel test
because normally they are often too brittle. Eventually this
would influence the results of the test. Other than tested, the
result cannot be applied one-to-one to combinations of
materials.
Advantage:
Already known from PCB technology.
Disadvantage:
Dimensions of circuit paths are too large to be used in
LDS- MID.
Minimum layer thickness ≥ 35 µm (otherwise galvanic
reinforcement is necessary).
Shear Force Measurement test: Though the shear force
measurement is particularly used in the field of PCB technology
to measure the mechanical strength of the interconnection
technology between the applied electronic components and
conductor track this method can also be applied conditionally to
measure the adhesion strength of the metallization on the
substrate. A chisel shears off components parallel to the
conductor track and thus measures the necessary force as shown
in Fig. 12.
Fig. 12: Schematic illustration of Shear force measurement [5]
8. One important parameter is that the width of the shear chisel
should be narrower than the distance between the junctions of
conductor track and component. Without contacting the surface
of the substrate, the shearing tool should get in touch with the
component as far at the bottom as possible. The shear chisel
must be placed parallel to the component, otherwise a uniform
force distribution will not be present over the component. In this
case, not only the shear force but also a peeling force is recorded
which eventually distorts the result.
Fig. 13: Different fractures during shear force measurement on MID [5].
Apart from the shear force measurement, the fracture faces have
to be analyzed. In Fig. 13 different types of fracture faces after
shear force measurement on MID has been shown where in
section 1, a fracture joint is shown, in section 2, the wrong
application of the procedure occurred. It can also be observed
that while shearing off the component, the chisel moved into the
substrate material. In section 3, a direct fracture in the
component is shown. In section 4, a mixed fracture is shown as
on the right side fracture occurred between metallization and
substrate while on the left side in the solder joint. If the occurred
fracture is between metallization and substrate, as shown in
section 5, a direct conclusion can be made regarding the
metallization adhesion. When it comes to MID, this type of
failure or fracture occurs more often. However, the shear test can
also be performed in a more direct method without electronic
components. This variant of the test is very difficult to proceed
due to the thin metallization layers and the beads caused by the
laser structuring process. Another special version of this method
is used to measure the shear force named micro chisel test where
conductor tracks are peeled off using a micro chisel while forces
in X and Z direction are recorded.
Advantage:
During analysis quantifiable values occur.
Disadvantage:
Difficult procedure to proceed because of thin
metallization layers and beads of laser structuring
process.
High investment in equipment.
Hot Pin Pull test: This new method for determining the
adhesion strength is easy to use and also used for the
characterization of PCB pad cratering. This test can be carried
out with Nordson DAGE’s micro material testing system Dage
Fig. 14: Hot pin pull test using the testing system Dage 4000Plus.
4000Plus as shown in Fig. 14. Straight copper pins with a
diameter of 900 μm are used for this test. Either plain copper
pins or pins with tinned end both can be used. Test pins are
widely available with a tip radius of 100 μm, 300 μm or 450 μm
as shown in Fig. 15. There is a special heater cartridge into
which the test pins are vertically inserted and they are held in
place by a spring-loaded mechanism. A user-defined time-
temperature profile can be assigned to the heater cartridge in
which the setup for the profile can be defined by temperature
and time criteria for the reflow in six consecutive stages shown
as Fig. 16.
Fig. 15: Schematic illustration of hot pin pull test [5].
The inserted pin is positioned either into a previously dispensed
solder paste on the test structure contacting the metallized
surface (untinned pin) or on the test structure (tinned pin).
According to this temperature profile, the pin temperature
ramps up once the test is started. In this method, the pin is
soldered to the metallized test structure. By pulsing compressed
air along the pin and onto the test sample the cooling process is
handled. During the running process when the temperature
reaches T6, the clamping mechanism of the cartridge fixes the
pin and an increasing tensile force is applied by the pull-off
process to the pin. Hence, after applying particular amount of
force the detachment of metallization from the substrate occurs
and it gets recorded and logged. From the size of the detached
area and the maximum force applied, the adhesion strength can
be calculated.
9. Fig. 16: Temperature profile of hot pin pull test [5].
In Fig. 17, the hot pin pull method has been shown in total of
eight sections. The test was performed with an untinned pin
with a tip of radius of 450 µm and low melting SnBi solder paste
according to [5]. LDS process laser structure has been used in
the test structure with the metallized circles having a diameter
of 1mm. In section 1, the solder paste that has been dispensed
on the metallization pad and the pin positioned over the test
structure is shown. Needless to say, according to the size of the
test area, the amount of solder was adapted. In section 2, the
sample has been shown right after the pin dipped into the solder.
Section 3 shows the picture during the heating process. As the
metallized test structure is wetted by the flux, a transition is
built up by the solder from pin to test structure in conical shape.
As the process continues in section 4, the single solder particles
start to melt when the melting temperature of the solder is
reached (melting temperature of SnBi is 137 degree Celsius).
As seen in section 5, the solder being completely melted covers
the test structure in a cone shape surrounding the pin. After that
when the cooling process takes place the pin gets completely
covered by the circular structure of the solidified solder as
shown in section 6.
Fig. 17: Process steps of hot pin pull test [5].
In section 7, the exposed surface of the substrate is shown after
the test metallization is pulled-off. In section 8, the pin with the
detached metallization is connected by the solder joint [6].
Advantage:
A low standard deviation (below 10%) can be obtained.
Different pad sizes can be used on the substrate.
This method allows the direct use of serial parts.
The process changes can be detected by the resolution
of test method as it is sensitive enough to do so.
Disadvantage:
Special set of apparatus is required to perform the test.
Conditions:
As low as possible temperature profile.
Test should be continued with completely wetted
structures for reproducible test conditions.
Machine parameters such as take-off speed should be
set properly.
Amount of solder paste must be taken into account with
the change of test pad.
Different test geometries can be set only if other
parameters like temperature profile does not have a
massive impact.
According to the change of pad and solder paste the
temperature profile must be taken into account.
Major investigations on hot pin pull test: According to [5],
all investigations regarding the hot pin pull test were performed
with low melting SnBi solder with melting point of 138 ºC and
blank copper pins and LDS process have been used to produce
all test structures. The influence of the temperature on the test
results was one of main focuses of the hot pin pull test. Samples
which were used as test samples were made of liquid crystal
polymer (LCP, Vectra E840i LDS) and had circles with a
diameter of 1 mm. Depending on the test structure size the
amount of solder paste was adapted accordingly and depending
on the amount of solder paste the necessary peak temperature
and time period for the reflow process were fixed. In pre trials,
such a temperature profile was determined so that the substrate
is not damaged or the adhesion strength is not influenced and
also a complete wetting of the test circles got ensured. For a
period of 20 second with a peak temperature of 170 °C, this
profile was stepped up increasing the peak temperature in two
steps by 80 °C each and the results show a significant impact on
the measured adhesion strength on Fig. 18. As the peak
temperature increases the adhesion strength considerably
decreases. With a peak temperature of 330 °C, the fracture face
and the cross section show a damage on the substrate material in
contrast to a peak temperature of 170 °C. So, temperature profile
should be determined as soft as possible to avoid influencing the
results of adhesion test [5].
Fig. 18: Adhesion strengths at different peak temperatures of hot pin pull test
[5].
Other main focuses on the investigation is the complete wetting
of the test structure with solder paste as it ensures the
reproducible application of the hot pin pull test. For the complete
wetting of the test structure the properties and condition of the
metallization e.g. roughness, impurities plays an important role
as well. In Fig. 19 detached test circles having a diameter of 2
mm in different solder wetting conditions are shown. As shown
in section 1 and 2 of Fig. 19, there is a possibility of uncontrolled
rip out of the whole metallized area (section 1) and a complete
10. detachment of the test structure due to lack of complete wetting
with solder paste on those two sections. As shown in section 3,
a completely wetted test structure with a fully detached
metallization should be used for the proper analysis of the test.
Fig. 19: In hot pin pull test different detached structures with different solder
wetting conditions [5].
Significant differences were seen while investigating the solder
paste amount used for test circles with diameter of 1 mm and 3
mm as shown in Fig. 19. According to [5], a volume of
0.045±0.01 mm³ solder paste was required to completely wet the
1 mm circle and the same amount was used for 3 mm circles as
well. It is been calculated that the metallization with 0.79 mm²
of area was totally pulled off for the 1 mm circles (Fig. 18,
section 3) while on the 3 mm circles, a partial rip out took place
to the metallized areas from 0.53 mm² until 0.86 mm² with a
mean of 0.62 mm² (Fig. 19, section 1). As a matter of fact the
more the uncontrolled rip out the higher the standard deviation.
And additional forces are required to rip out a part of
metallization which results in the higher adhesion strength. The
results could vary to certain extent depending on the layer
properties and thicknesses. It is also known that the smaller the
test areas are the more the adhesion strength increases.
Fig. 20: In hot pin pull test result of using different detached structures with
different solder wetting conditions [5].
VI. COMPARISON OF TEST METHODS
According to [5], four different samples (V1 - V4) were used
where substrate material LCP Vectra E840i LDS was used as
V1, V2 and PA4T/X Vestamid HTplus TGP 3586 was used as
V3, V4. V1 and V3 samples had comparatively smoother
structure while V2 and V4 had comparatively rougher ones.
With a diameter of 1 mm, the hot pin pull test was performed on
test circles while test circles with a diameter of 3 mm was used
to perform the pull-off test, the dolly being bonded with an
adhesive onto the test structures.
Fig. 21: Comparison of hot pin pull test, pull-off test and shear force
measurement test [5].
The temperature profile is shown in Fig. 16 for hot pin pull test.
On the corresponding land patterns for the measurement of shear
force, CR 0402 components were applied using SnAgCu solder.
For assuring comparability, according to [5], all tests were
performed after vapor phase soldering at a temperature of 230ºC.
Unfortunately due to different test methods of these different
tests, a direct comparison of adhesion strength values cannot be
Pull-off Test
Shear force measurement Test
V3 - PPA Vestamid HTplus TGP3586 𝑅 𝑧 = 13.98 µ𝑚
V2 - LCP Vectra E840i LDS 𝑅 𝑧 = 13.98 µ𝑚
V4 - PPA Vestamid HTplus TGP3586 𝑅 𝑧 = 32.73 µ𝑚
V1 - LCP Vectra E84i LDS 𝑅 𝑧 = 11.03 µ𝑚
Hot pin pull Test
11. drawn. However, Fig. 21 implies to the similar trends shown by
the results of the tests of measuring the adhesion strength of the
investigated samples. For a basic evaluation of the adhesion
strength of metallized structures on MID, all regarded test
methods are suitable. But when it comes to the standard
deviation however, it can be seen that significant differences
appear on them. With hot pin pull test the lowest standard
deviation in a range of about 5% could be achieved while the
values achieved with the shear force measurement are twice as
high compared to that. With pull-off test, standard deviation
reached to more than 25%. Important facts to be mentioned here
that the efforts for performing these test vary widely. The
preparation efforts for the pull-off test are comparatively high
with the application of the adhesive, the positioning of the dolly
and the curing process and also it includes the manual process
which increases the influence of the user even furthermore. For
shear force measurement, the test cannot be used to determine
the initial adhesion of a metallization and the test can only be
performed quite fast if the components are already applied on
the specimen but due to different fracture faces the usable
results can be very much limited. On the other hand, hot pin pull
test has advantage on the preparation effort over other test
methods mentioned above, but only if the required apparatus
are present. There are also some significant differences between
hot pin pull test and conventional pull-off test. As the MID
structures don’t offer much planar surface so the large size of
the dolly and manual application of adhesives are not effective
whereas hot pin pull test offers smaller test pad usage, less
manual activity and partly automated process.
VII. CONCLUSION
In this study, the advantages of choosing Laser Direct
Structuring process over other processes, optimum LDS
parameters with its effects on groove dimensions and quality
have been investigated. Also the importance of adhesion and
comparison between different adhesion strength measuring tests
have been mentioned and investigated. We can summarize and
conclude notable investigations as given below-
There are sets of LDS parameters to produce certain
thickness of circuit line and minimum space between two
circuit lines. The minimum space distance between two
circuit lines can be achieved in the range of 50 to 60 µm
while the minimum width of the circuit line of 48.5 µm can
also be achieved. Metallization defects may start to occur if
the minimum space between the two lines are reduced to less
than 50 µm.
The edge dimension namely the width needs to be reduced to
the lowest possible value to avoid or reduce the metallization
defects. As a result it increases the quality of the
metallization, hence the quality of MID products.
If the necessary apparatus are present then the hot pin pull
test can be a very good alternative to the conventional
methods for testing the adhesion strength. The method itself
being partly automated makes the influence of the user
correspondingly limited thus enabling the reproducibility of
the test to be quite high. For instance, the fact that the pin is
soldered to the test metallization while it is inserted in the
cartridge, minimized the risk that the tensile force is not
applied vertically. Also on account of the controlled heating
a reproducible temperature treatment is ensured and cooling
process gets executed by the heater cartridge.
In hot pin pull test, low standard deviation is achievable
compared to other test methods which makes it very
promising and also relatively low amount of efforts are
required for the preparation and performing the test.
Hot pin pull test also provides the possibility to use small test
structures e.g. circles with a diameter of 1mm, which can be
very helpful especially on three-dimensional MID parts,
where planar areas for larger test structure are quite rare.
However, as there are various influencing factors exist which
bear a considerable impact on the results, further
investigations in detailed manner and necessary standards
and guidelines are required that enable a uniform
performance of the test.
REFERENCES
[1] Joerg Franke, “Three Dimensional Molded Interconnect Devices (3D-
MID), April 2013
[2] Bassim Bachy and Joerg Franke, “Experimental Investigation and
Optimization for the Effective Parameter in the Laser Direct Structuring
Process”, JLMN- Journal of Laser Micro/Nanoengineering 2015.
[3] Angelika Paproth, Klaus-Jürgen Wolter, and Rumen Deltschew,
“Adhesion of Polymer/Metal Bonds for Molded Interconnect Devices
(MID)”, June 2005.
[4] Klaus Zeh, “Selection and Qualification of a Test Method for Determining
Adhesion of MID Metallization in the LDS Technology”, 2012.
[5] Thomas Kuhn and Joerg Franke, “Test Methods and Influencing Factors
for the Adhesion Strength Measurement of Metallized Structures on
Thermoplastic Substrates”, EPTC IEEE 2014.
[6] HARTING Mitronics- Christian Goth, “Hot Pin Pull Method – Mew
Test Procedure for the Adhesion Measurement for 3D- MID”, 11th
International Congress MID 2014.