1) The document reviews methods for fabricating investment casting patterns in the micrometer range for producing small metal parts.
2) Common approaches use micro injection molding of plastics like PMMA, but this has limitations. Other microfabrication methods are considered.
3) Methods discussed include micro cutting techniques like turning and milling of plastics, as well as laser machining. These allow production of patterns with tight tolerances needed for micro investment casting.
Discusses about photolithography, mask design, wet and dry bulk etching, bonding, thin film deposition and removal, metallization, sacrificial process and other inorganic processes.
This document provides an overview of microfabrication and nanofabrication techniques. It discusses both top-down approaches like photolithography, nanoimprint lithography, and nanosphere lithography as well as bottom-up techniques such as carbon nanotube synthesis and molecular self-assembly. The document also covers common microfabrication processes like thin film deposition, doping, oxidation, etching, and lithography. It provides details on lithography techniques, thin film deposition methods like CVD and PVD, and etching approaches including wet and dry etching.
The document discusses microfabrication techniques for manufacturing nano-scale structures. It describes both top-down approaches that sculpt materials from larger to smaller sizes (such as photolithography, nanoimprint lithography, and nanosphere lithography) and bottom-up approaches that assemble structures from smaller building blocks (like carbon nanotube synthesis and molecular self-assembly). Common microfabrication processes discussed include lithography, thin film deposition, doping, etching, and bonding. Both isotropic and anisotropic etching techniques are covered.
Micro manufacturing involves processes used to fabricate micro components or create micro features on parts. Some key micro manufacturing processes include diamond turning, laser welding, and micro drilling. Diamond turning can machine microgrooves as small as 2.5 μm wide by 1.6 μm deep. Laser beam welding comes in two types: surface heating and through transmission infrared welding. Nano manufacturing deals with even smaller scales down to 1 nanometer. Approaches include top-down methods like focused beam lithography and nanoimprint lithography as well as bottom-up methods such as chemical vapor deposition and dip pen lithography. These techniques have applications in precision manufacturing of devices used in areas like semiconductor fabrication, medical devices, and more.
Nanomanufacturing is both the generation of nanoscaled materials, which can be powders or liquids, and the assembling of parts "base up" from nanoscaled materials or "top down" in littlest strides for high exactness, utilized as a part of a few advances, for example, laser removal, drawing and others. Nanomanufacturing varies from atomic assembling, which is the produce of complex, nanoscale structures by method for nonbiological mechanosynthesis.
The document discusses nanofabrication techniques used to design nanomaterials and devices measured in nanometers. It describes common nanofabrication processes like thin film deposition using physical vapor deposition or chemical vapor deposition, patterning using optical or e-beam lithography, and etching using wet or dry methods. Typical applications of nanofabrication include manufacturing printed circuit boards, microcontrollers, and MEMS devices used in smartphones and computers.
Micro-electromechanical systems (MEMS) combine mechanical and electrical components on a silicon chip using microfabrication techniques. MEMS can sense, control, and actuate on a microscale and generate macroscale effects. Common MEMS fabrication techniques include deposition, patterning, etching, and micromachining of materials like silicon and metals. There are three main micromachining methods: bulk micromachining which removes silicon substrate material, surface micromachining which builds up thin films, and high-aspect-ratio micromachining (HARM) which allows molding of high-resolution microstructures. LIGA is a specialized HARM technique that uses x-rays to pattern thick photoresist
Discusses about photolithography, mask design, wet and dry bulk etching, bonding, thin film deposition and removal, metallization, sacrificial process and other inorganic processes.
This document provides an overview of microfabrication and nanofabrication techniques. It discusses both top-down approaches like photolithography, nanoimprint lithography, and nanosphere lithography as well as bottom-up techniques such as carbon nanotube synthesis and molecular self-assembly. The document also covers common microfabrication processes like thin film deposition, doping, oxidation, etching, and lithography. It provides details on lithography techniques, thin film deposition methods like CVD and PVD, and etching approaches including wet and dry etching.
The document discusses microfabrication techniques for manufacturing nano-scale structures. It describes both top-down approaches that sculpt materials from larger to smaller sizes (such as photolithography, nanoimprint lithography, and nanosphere lithography) and bottom-up approaches that assemble structures from smaller building blocks (like carbon nanotube synthesis and molecular self-assembly). Common microfabrication processes discussed include lithography, thin film deposition, doping, etching, and bonding. Both isotropic and anisotropic etching techniques are covered.
Micro manufacturing involves processes used to fabricate micro components or create micro features on parts. Some key micro manufacturing processes include diamond turning, laser welding, and micro drilling. Diamond turning can machine microgrooves as small as 2.5 μm wide by 1.6 μm deep. Laser beam welding comes in two types: surface heating and through transmission infrared welding. Nano manufacturing deals with even smaller scales down to 1 nanometer. Approaches include top-down methods like focused beam lithography and nanoimprint lithography as well as bottom-up methods such as chemical vapor deposition and dip pen lithography. These techniques have applications in precision manufacturing of devices used in areas like semiconductor fabrication, medical devices, and more.
Nanomanufacturing is both the generation of nanoscaled materials, which can be powders or liquids, and the assembling of parts "base up" from nanoscaled materials or "top down" in littlest strides for high exactness, utilized as a part of a few advances, for example, laser removal, drawing and others. Nanomanufacturing varies from atomic assembling, which is the produce of complex, nanoscale structures by method for nonbiological mechanosynthesis.
The document discusses nanofabrication techniques used to design nanomaterials and devices measured in nanometers. It describes common nanofabrication processes like thin film deposition using physical vapor deposition or chemical vapor deposition, patterning using optical or e-beam lithography, and etching using wet or dry methods. Typical applications of nanofabrication include manufacturing printed circuit boards, microcontrollers, and MEMS devices used in smartphones and computers.
Micro-electromechanical systems (MEMS) combine mechanical and electrical components on a silicon chip using microfabrication techniques. MEMS can sense, control, and actuate on a microscale and generate macroscale effects. Common MEMS fabrication techniques include deposition, patterning, etching, and micromachining of materials like silicon and metals. There are three main micromachining methods: bulk micromachining which removes silicon substrate material, surface micromachining which builds up thin films, and high-aspect-ratio micromachining (HARM) which allows molding of high-resolution microstructures. LIGA is a specialized HARM technique that uses x-rays to pattern thick photoresist
The document discusses various laser micromachining techniques including pyrolytic and photolytic processing. It describes the fundamentals of lasers including stimulated emission and different laser types such as solid state, diode, and Ti-sapphire lasers. The effects of nanosecond, picosecond, and femtosecond laser pulses on material processing are examined for applications such as microfabrication.
Bulk micromachining involves selectively removing substrate material through chemical wet etching to create miniaturized mechanical components. Etching can be anisotropic, isotropic, or reactive ion etching. Surface micromachining forms MEMS sensors on the wafer using deposited thin films and patterning layers. High aspect ratio micromachining combines surface and bulk techniques to allow for high aspect ratio silicon structures through thick silicon layers, enabling immunity to parasitic vibrations.
The document discusses bottom-up processing of nanomaterials. Bottom-up processing uses a self-assembly approach by selectively adding atoms to create nanostructures, unlike the top-down approach which removes material. Bottom-up processing allows for smaller feature sizes than photolithography and is needed to create some nanostructures like carbon nanotubes. While it has advantages like smaller sizes and material efficiency, bottom-up processing faces challenges like ensuring correct assembly and contamination. The document outlines examples of bottom-up applications and strategies to control growth, and predicts bottom-up will become more prevalent for technologies like organic semiconductors that require its approach.
This document discusses nanotechnology and provides an overview of top-down and bottom-up approaches to nanomaterial synthesis. It describes that the bottom-up approach involves molecular components arranging themselves into more complex structures from the smallest level, while the top-down approach uses larger external tools to shape and assemble materials into the desired nanoscale structures. Characterization techniques for nanomaterials include SEM, TEM, AFM, XRD, FTIR, and NMR. Applications mentioned include medical imaging, disease detection, agriculture, and environmental remediation.
Nanomaterials are commonly defined as materials with at least one dimension measuring less than 100 nanometers. They can exist in single, spherical, tubular, or irregular shapes in one, two, or three dimensions. Nanomaterials are important because their ultra-small size enables benefits like transparency in coatings and high strength with minimal material. Their large surface area enhances reactivity, strength, and electrical properties compared to larger particles of the same composition. Nanomaterials are created through top-down methods like grinding or bottom-up sol-gel processes and have applications in ceramics, semiconductors, powders, and thin films due to their unique mechanical, electrical, and optical properties at the nanoscale.
The document discusses various methods for synthesizing nanomaterials, including top-down and bottom-up approaches. Top-down approaches begin with bulk materials and make them smaller through processes like lithography or milling. Bottom-up approaches build materials up from atomic or molecular levels using chemical synthesis or self-assembly. Specific bottom-up methods discussed include sol-gel processing, chemical vapor deposition, and chemical reduction of metal salts to produce colloidal nanoparticles. The document compares advantages and limitations of different nanomaterial synthesis techniques.
This document provides an overview of nanochemistry including definitions of related terms like nanoscience and nanotechnology. It discusses common nanoscale structures such as nanocrystals, nanotubes, and nanowires. Methods for preparing nanomaterials include top-down processes that break down bulk materials and bottom-up techniques involving the assembly of atoms or particles. Properties and characterization techniques are also summarized along with potential application areas for nanotechnology across various industries.
The document discusses various nanofabrication techniques. Photolithography has limitations based on the optical diffraction limit. Electron beam lithography allows for higher resolution down to 5 nm but is slow and expensive. Soft lithography uses elastomeric stamps to transfer self-assembled monolayers in a parallel, low-cost manner via techniques like nanoimprint lithography and microcontact printing. Scanned probe techniques like atomic force microscopy and scanning tunneling microscopy can directly oxidize surfaces on the nanoscale.
This document discusses modeling approaches for thin-film manufacturing and product operation. It describes modeling a thin-film CdTe photovoltaic manufacturing process to analyze film uniformity and validate an improved hardware design. It also models a new thin-film PV module design to analyze its thermal response under various operating conditions. Simulation provides insight into thin-film processes and products that would otherwise be difficult to obtain.
Fiber-optic lines carry digital information over long distances using thin glass strands. They transmit light through total internal reflection within the core, which is surrounded by cladding that reflects the light back into the core. Fiber optics provide stable, high-speed communication that is hardly influenced by external factors due to transmitting light through the core over great distances.
The document discusses how the mechanical properties of nanomaterials are significantly different than their conventional counterparts. It provides examples of how nanomaterials make cutting tools harder and longer-lasting, allow for smaller microdrills, can improve fuel efficiency in automobiles through heat retention coatings, enhance fatigue life and strength in aerospace components, and enable ductile and machinable ceramics. Nanocrystalline ceramics can be pressed and sintered at lower temperatures than conventional ceramics.
3D Printing with Nanomaterials, Metamaterials and Ceramics. Michael Petch
Presentation: Novel Materials: Production, Processing and Performance
Plastics and metals are the dominant materials in the current 3D printing field. This talk looked at lesser publicized materials and related processes. Specifically, ceramics, graphene (and other nano-materials), hydro & aerogels in the context of 3D printing. The current academic research, commercial applications (and relevant patents), production of materials and the possible future developments will be reviewed with reference to independent research conducted for this presentation.
The document discusses the ball milling method for producing nano materials. It involves using a ball mill, which rotates around a horizontal axis partially filled with the material to be ground plus grinding media like balls. The balls crush the solid material into nano crystallites due to the gravity and kinetic forces as they rotate at high energy inside the container. Some examples given are using ball milling to produce carbon nanotubes, boron nitride nanotubes, metal oxide nano crystals like cerium oxide and zinc oxide. Ball milling of graphite can also produce nanostructured graphite for hydrogen storage applications.
surface texturing by rapid scanning of pulsed laser beamDi (Dustin) Liu
This document discusses using rapid laser scanning to texture surfaces for applications such as solar cells and military equipment. It demonstrates that laser scanning allows for high flexibility and precision compared to other texturing methods. The document investigates different laser parameters and their effects on texturing mechanisms and performance. Optimal parameters were identified that enhanced light trapping for solar cells through crystalline structures and enabled stealth and thermal functions for military applications.
The document discusses various applications of nanotechnology in engineering and construction materials, including using nanoparticles to improve the strength and properties of concrete, steel, wood, and glass. Nanoparticles can enhance qualities like compressive strength, corrosion resistance, self-healing abilities, and sustainability. The document evaluates how nanotechnology may lead to improved construction systems and materials in the future.
The document discusses various applications of nanomaterials. It describes how nanotechnology is used in industries like automotive, engineering, medicine, cosmetics and textiles. It also discusses energy applications like nanofabrication for new ways to capture, store and transfer energy. Pharmaceutical applications of nanomaterials include drug delivery, tissue engineering, medical implants and diagnostics. Nanotechnology is also used in water purification through processes like nanofiltration and reverse osmosis. Thin film solar cells and dye sensitized solar cells that use nanomaterials are discussed as energy applications. Perovskite solar cells which can achieve high efficiencies are also summarized.
Nano material and surface engineering pptVipin Singh
The document discusses the use of nano materials in surface engineering. It provides an introduction to nano materials and their applications. Some key points include:
- Nano materials have at least one dimension between 1-100 nanometers. They can exist naturally or be engineered.
- Surface engineering techniques like coatings and treatments are used to improve material properties and resistance to degradation.
- Nano materials can be used in coatings and composites to enhance mechanical, optical, and other properties when integrated as a reinforcing phase.
- A case study examines how nanostructured TiN/CrN coatings deposited at different temperatures influence mechanical and tribological properties. The lowest deposition temperature produced the highest hardness and wear
Nano-material and its benefits in the Environmental ApplicationMusaddiq Ali
Nanomaterial is defined as material with dimensions less than 100nm. Nanotechnology involves manipulating nanomaterials to create new large-scale materials with improved properties. Nanoparticles can be organic such as polymeric or inorganic such as gold. Nanomaterials provide benefits in environmental applications such as energy savings through weight reduction and optimized function in vehicles and buildings. They can also reduce use of raw materials through miniaturization.
This lecture helps to gain an understanding of the interaction between part design, tool design and forging process parameters in order to achieve optimum quality forged products. General understanding of metallurgy and deformation processes is assumed.
International Journal of Engineering and Science Invention (IJESI)inventionjournals
International Journal of Engineering and Science Invention (IJESI) is an international journal intended for professionals and researchers in all fields of computer science and electronics. IJESI publishes research articles and reviews within the whole field Engineering Science and Technology, new teaching methods, assessment, validation and the impact of new technologies and it will continue to provide information on the latest trends and developments in this ever-expanding subject. The publications of papers are selected through double peer reviewed to ensure originality, relevance, and readability. The articles published in our journal can be accessed online.
The document discusses various laser micromachining techniques including pyrolytic and photolytic processing. It describes the fundamentals of lasers including stimulated emission and different laser types such as solid state, diode, and Ti-sapphire lasers. The effects of nanosecond, picosecond, and femtosecond laser pulses on material processing are examined for applications such as microfabrication.
Bulk micromachining involves selectively removing substrate material through chemical wet etching to create miniaturized mechanical components. Etching can be anisotropic, isotropic, or reactive ion etching. Surface micromachining forms MEMS sensors on the wafer using deposited thin films and patterning layers. High aspect ratio micromachining combines surface and bulk techniques to allow for high aspect ratio silicon structures through thick silicon layers, enabling immunity to parasitic vibrations.
The document discusses bottom-up processing of nanomaterials. Bottom-up processing uses a self-assembly approach by selectively adding atoms to create nanostructures, unlike the top-down approach which removes material. Bottom-up processing allows for smaller feature sizes than photolithography and is needed to create some nanostructures like carbon nanotubes. While it has advantages like smaller sizes and material efficiency, bottom-up processing faces challenges like ensuring correct assembly and contamination. The document outlines examples of bottom-up applications and strategies to control growth, and predicts bottom-up will become more prevalent for technologies like organic semiconductors that require its approach.
This document discusses nanotechnology and provides an overview of top-down and bottom-up approaches to nanomaterial synthesis. It describes that the bottom-up approach involves molecular components arranging themselves into more complex structures from the smallest level, while the top-down approach uses larger external tools to shape and assemble materials into the desired nanoscale structures. Characterization techniques for nanomaterials include SEM, TEM, AFM, XRD, FTIR, and NMR. Applications mentioned include medical imaging, disease detection, agriculture, and environmental remediation.
Nanomaterials are commonly defined as materials with at least one dimension measuring less than 100 nanometers. They can exist in single, spherical, tubular, or irregular shapes in one, two, or three dimensions. Nanomaterials are important because their ultra-small size enables benefits like transparency in coatings and high strength with minimal material. Their large surface area enhances reactivity, strength, and electrical properties compared to larger particles of the same composition. Nanomaterials are created through top-down methods like grinding or bottom-up sol-gel processes and have applications in ceramics, semiconductors, powders, and thin films due to their unique mechanical, electrical, and optical properties at the nanoscale.
The document discusses various methods for synthesizing nanomaterials, including top-down and bottom-up approaches. Top-down approaches begin with bulk materials and make them smaller through processes like lithography or milling. Bottom-up approaches build materials up from atomic or molecular levels using chemical synthesis or self-assembly. Specific bottom-up methods discussed include sol-gel processing, chemical vapor deposition, and chemical reduction of metal salts to produce colloidal nanoparticles. The document compares advantages and limitations of different nanomaterial synthesis techniques.
This document provides an overview of nanochemistry including definitions of related terms like nanoscience and nanotechnology. It discusses common nanoscale structures such as nanocrystals, nanotubes, and nanowires. Methods for preparing nanomaterials include top-down processes that break down bulk materials and bottom-up techniques involving the assembly of atoms or particles. Properties and characterization techniques are also summarized along with potential application areas for nanotechnology across various industries.
The document discusses various nanofabrication techniques. Photolithography has limitations based on the optical diffraction limit. Electron beam lithography allows for higher resolution down to 5 nm but is slow and expensive. Soft lithography uses elastomeric stamps to transfer self-assembled monolayers in a parallel, low-cost manner via techniques like nanoimprint lithography and microcontact printing. Scanned probe techniques like atomic force microscopy and scanning tunneling microscopy can directly oxidize surfaces on the nanoscale.
This document discusses modeling approaches for thin-film manufacturing and product operation. It describes modeling a thin-film CdTe photovoltaic manufacturing process to analyze film uniformity and validate an improved hardware design. It also models a new thin-film PV module design to analyze its thermal response under various operating conditions. Simulation provides insight into thin-film processes and products that would otherwise be difficult to obtain.
Fiber-optic lines carry digital information over long distances using thin glass strands. They transmit light through total internal reflection within the core, which is surrounded by cladding that reflects the light back into the core. Fiber optics provide stable, high-speed communication that is hardly influenced by external factors due to transmitting light through the core over great distances.
The document discusses how the mechanical properties of nanomaterials are significantly different than their conventional counterparts. It provides examples of how nanomaterials make cutting tools harder and longer-lasting, allow for smaller microdrills, can improve fuel efficiency in automobiles through heat retention coatings, enhance fatigue life and strength in aerospace components, and enable ductile and machinable ceramics. Nanocrystalline ceramics can be pressed and sintered at lower temperatures than conventional ceramics.
3D Printing with Nanomaterials, Metamaterials and Ceramics. Michael Petch
Presentation: Novel Materials: Production, Processing and Performance
Plastics and metals are the dominant materials in the current 3D printing field. This talk looked at lesser publicized materials and related processes. Specifically, ceramics, graphene (and other nano-materials), hydro & aerogels in the context of 3D printing. The current academic research, commercial applications (and relevant patents), production of materials and the possible future developments will be reviewed with reference to independent research conducted for this presentation.
The document discusses the ball milling method for producing nano materials. It involves using a ball mill, which rotates around a horizontal axis partially filled with the material to be ground plus grinding media like balls. The balls crush the solid material into nano crystallites due to the gravity and kinetic forces as they rotate at high energy inside the container. Some examples given are using ball milling to produce carbon nanotubes, boron nitride nanotubes, metal oxide nano crystals like cerium oxide and zinc oxide. Ball milling of graphite can also produce nanostructured graphite for hydrogen storage applications.
surface texturing by rapid scanning of pulsed laser beamDi (Dustin) Liu
This document discusses using rapid laser scanning to texture surfaces for applications such as solar cells and military equipment. It demonstrates that laser scanning allows for high flexibility and precision compared to other texturing methods. The document investigates different laser parameters and their effects on texturing mechanisms and performance. Optimal parameters were identified that enhanced light trapping for solar cells through crystalline structures and enabled stealth and thermal functions for military applications.
The document discusses various applications of nanotechnology in engineering and construction materials, including using nanoparticles to improve the strength and properties of concrete, steel, wood, and glass. Nanoparticles can enhance qualities like compressive strength, corrosion resistance, self-healing abilities, and sustainability. The document evaluates how nanotechnology may lead to improved construction systems and materials in the future.
The document discusses various applications of nanomaterials. It describes how nanotechnology is used in industries like automotive, engineering, medicine, cosmetics and textiles. It also discusses energy applications like nanofabrication for new ways to capture, store and transfer energy. Pharmaceutical applications of nanomaterials include drug delivery, tissue engineering, medical implants and diagnostics. Nanotechnology is also used in water purification through processes like nanofiltration and reverse osmosis. Thin film solar cells and dye sensitized solar cells that use nanomaterials are discussed as energy applications. Perovskite solar cells which can achieve high efficiencies are also summarized.
Nano material and surface engineering pptVipin Singh
The document discusses the use of nano materials in surface engineering. It provides an introduction to nano materials and their applications. Some key points include:
- Nano materials have at least one dimension between 1-100 nanometers. They can exist naturally or be engineered.
- Surface engineering techniques like coatings and treatments are used to improve material properties and resistance to degradation.
- Nano materials can be used in coatings and composites to enhance mechanical, optical, and other properties when integrated as a reinforcing phase.
- A case study examines how nanostructured TiN/CrN coatings deposited at different temperatures influence mechanical and tribological properties. The lowest deposition temperature produced the highest hardness and wear
Nano-material and its benefits in the Environmental ApplicationMusaddiq Ali
Nanomaterial is defined as material with dimensions less than 100nm. Nanotechnology involves manipulating nanomaterials to create new large-scale materials with improved properties. Nanoparticles can be organic such as polymeric or inorganic such as gold. Nanomaterials provide benefits in environmental applications such as energy savings through weight reduction and optimized function in vehicles and buildings. They can also reduce use of raw materials through miniaturization.
This lecture helps to gain an understanding of the interaction between part design, tool design and forging process parameters in order to achieve optimum quality forged products. General understanding of metallurgy and deformation processes is assumed.
International Journal of Engineering and Science Invention (IJESI)inventionjournals
International Journal of Engineering and Science Invention (IJESI) is an international journal intended for professionals and researchers in all fields of computer science and electronics. IJESI publishes research articles and reviews within the whole field Engineering Science and Technology, new teaching methods, assessment, validation and the impact of new technologies and it will continue to provide information on the latest trends and developments in this ever-expanding subject. The publications of papers are selected through double peer reviewed to ensure originality, relevance, and readability. The articles published in our journal can be accessed online.
11.a review on micro fabrication methods to produce investment patterns of mi...Alexander Decker
This document reviews microfabrication methods for producing investment casting patterns in the micrometer range. It discusses several methods including micro cutting, laser machining, micro injection molding, and rapid prototyping. Micro cutting techniques like turning and milling can produce patterns out of plastics like PMMA with high accuracy and surface quality. Laser machining uses ablation to fabricate microstructures in materials like PMMA but can cause distortion. Micro injection molding mass produces plastic microparts but requires micro-scale molds. Rapid prototyping builds 3D patterns layer-by-layer through photopolymerization of resins or two-photon polymerization of materials like PMMA. The best process depends on factors like batch size,
Ontologisms have been applied to many applications in recent years, especially on Sematic Web, Information
Retrieval, Information Extraction, and Question and Answer. The purpose of domain-specific ontology
is to get rid of conceptual and terminological confusion. It accomplishes this by specifying a set of generic
concepts that characterizes the domain as well as their definitions and interrelationships. This paper will
describe some algorithms for identifying semantic relations and constructing an Information Technology
Ontology, while extracting the concepts and objects from different sources. The Ontology is constructed
based on three main resources: ACM, Wikipedia and unstructured files from ACM Digital Library. Our
algorithms are combined of Natural Language Processing and Machine Learning. We use Natural Language
Processing tools, such as OpenNLP, Stanford Lexical Dependency Parser in order to explore sentences.
We then extract these sentences based on English pattern in order to build training set. We use a
random sample among 245 categories of ACM to evaluate our results. Results generated show that our
system yields superior performance.
The document defines and analyzes Boston's creative economy. It proposes a definition of the creative economy that includes artistic and cultural industries such as performing arts, publishing, film and video, museums, and independent artists. The definition outlines the creative production chain from content creation to distribution. It then provides a detailed breakdown of the creative economy into components using NAICS industry codes.
This document provides information on legal requirements, hazards, and safety practices in the workplace. It discusses employer and employee responsibilities under occupational health and safety laws. Various workplace hazards are outlined such as physical, chemical, ergonomic, and psychological hazards. Manual handling practices, fire safety including classifications and types of fire extinguishers, material safety data sheets, and emergency response procedures are summarized. Key aspects of maintaining a safe work environment through hazard identification and control are emphasized.
This document contains 20 analogies questions with 5 answer options each. It tests one's ability to understand relationships between pairs of words and concepts. The answers provided at the end analyze each question to explain the logical relationship between the paired words or concepts in the correct answer choice.
Flexible Manufacturing System system is the ideal answer to integral training in industry automation. The technology included in its different assembly stations.
The document discusses micromachining, which refers to machining processes that remove small amounts of material to achieve high geometric accuracy at the micro level. Key points include:
- Micromachining is used to manufacture micro-structures and parts 1-500 micrometers in size.
- There is a growing demand for miniaturized products, driving increased use of micromachining.
- Micromachining techniques include bulk micromachining, surface micromachining, LIGA, and laser micromachining.
- Micromachining has applications in fields like biotechnology, medical devices, optics, and sensors.
This document discusses MEMS (Micro Electro Mechanical Systems) technology. It begins by explaining that MEMS combines microelectronics and micromachining to create miniaturized systems on a chip. It then discusses some key fabrication techniques for MEMS like surface micromachining, bulk micromachining, and LIGA. Applications of MEMS discussed include communications, biotechnology, inertial sensors like accelerometers and gyroscopes, RF switches, and uses in consumer and industrial markets. Challenges for the future of MEMS include limited access to foundries for fabrication, challenges with design/simulation/modeling, and challenges with packaging and testing MEMS devices.
As most of modern devices are either getting smaller or requiring tinier components, the demand for plastic micro molding continues growing. Thus it is easy to guess - this presentation is going to dive us in peculiarities of micro injection molding technology.
This was SlideShare adapted from our companies blog post:
https://www.micromolds.eu/micromolding-in-depth-insights
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.
Production Techniques 2 - advanced machining techniques reportKerrie Noble
This document compares and contrasts four advanced machining processes: photo-chemical machining, electrical-discharge machining, laser-beam machining, and electro-chemical machining. It discusses the process capabilities and design considerations for each. Two case studies are presented on using electro-chemical machining for a biomedical implant and manufacturing small satellites. The document concludes that each process has strengths for different applications in industries like aerospace, electronics, automotive, and medical.
Steps towards mathematical modeling of microcasting process from mesoscopic p...Alexander Decker
This document summarizes steps towards mathematical modeling of microcasting from a mesoscopic point of view. It discusses that microcasting involves producing small metallic parts with high aspect ratios using molten metal cast into microstructured molds. The document then presents governing differential equations that can be used to model fluid flow in microcasting from a mesoscopic scale perspective. Specifically, it discusses that the Navier-Stokes equations can be applied given channel dimensions are far enough from molecular scales. Lastly, it provides classifications for channel size and discusses modeling approaches for multi-phase systems in microcasting.
Steps towards mathematical modeling of microcasting process from mesoscopic p...Alexander Decker
This document discusses steps towards developing a mathematical model of the microcasting process from a mesoscopic point of view. It begins by introducing microcasting and its applications. It then discusses structural dimensions in microcasting and challenges associated with decreasing size scales. The document outlines different scales (macro, meso, micro, nano) for modeling casting and solidification phenomena. It presents the governing differential equations needed to model fluid flow at the mesoscale level in microcasting. Finally, it discusses channel classification and indicates that flow channels in microcasting are typically in the range of mesochannels.
This document provides an overview of microelectromechanical systems (MEMS) technology. It discusses how MEMS devices are fabricated using modified silicon and non-silicon techniques to create tiny integrated systems combining mechanical and electrical components on the microscale. The document outlines common MEMS fabrication methods like surface micromachining, bulk micromachining, and LIGA. It also discusses MEMS design processes, packaging challenges, and applications. The future of MEMS is presented as enabling more advanced automotive, medical, and environmental applications through continued innovation in areas like foundry access and design tools.
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.
Advances in micro milling: From tool fabrication to process outcomesShivendra Nandan
This document summarizes a review article on advances in micro milling. It discusses micro milling cutter geometry, materials, fabrication techniques, material removal mechanisms, design and optimization methods, and performance when used for micromanufacturing. Key aspects covered include micro milling cutter designs like solid cutters and welded cutters, common materials like cemented carbides and coatings, modeling cutting forces and tool wear, and experimental studies of temperature and forces at the microscale.
A Review on Factors Affecting the Sheet Metal Blanking ProcessIJMER
Metal blanking is a widely used process in high volume production of sheet metal
components. The main objective of this paper is to present the study model to predict the shape of the cut
side. The study investigates the effect of potential parameters influencing the blanking process and their
interactions. Different methodology like use of simulation software’s (e.g. abacus,ansys),FEM,DOE tech
are applied. Finally, the factors affecting blanking process observed are Clearance ,tool wear, Sheet
Thickness, Material properties .
Influence of Thrust, Torque Responsible for Delamination in drilling of Glass...IDES Editor
Glass fabric sandwich composites are potentially
growing materials which satisfies the low strength to weight
fraction, thermal conductivity, high strength and long
operational lifetime required for key engineering applications
especially in the field of Mechanical and Aerospace structures.
With their wide range of application, their manufacturing
and machinability characteristics are interesting to
investigate. Drilling is one of the prime manufacturing
processes used in assembly lines of components for fastening
and joining two components. In this study, Glass Fabric – Epoxy
/ Rigid polyurethane foam sandwich hybrid composite is drilled
in Arix VMC 100 CNC drilling machine using High Speed
Steel (HSS) drill bit of three different diameters of 6 mm, 8
mm and 10 mm. A L9 orthogonal array is setup to investigate
the result. Two main parameters that contribute to
delamination are thrust and torque. Thus in this
investigation, thrust and torque responsible for the effect of
delamination and hole quality is studied experimentally.
Scanning Electron Microscope (SEM) images are taken for
the drilled hole laminate to support the result.
Industrial adoption of 3D Printing has been increasing gradually from prototyping to manufacturing of low volume customized parts. The need for customized implants like tooth crowns, hearing aids, and orthopedic-replacement parts has made the life sciences industry an early adopter of 3D Printing. Demand for low volume spare parts of vintage cars and older models makes 3D printing very useful in the automotive industry. It is possible to 3D print in a wide range of materials that include thermoplastics, thermoplastic composites, pure metals, metal alloys and ceramics. Right now, 3D printing as an end-use manufacturing technology is still in its infancy. But in the coming decades, and in combination with synthetic biology and nanotechnology, it has the potential to radically transform many design, production and logistics processes.
This document provides an overview of micro-nanomachining processes. It discusses micro-milling and micro-drilling techniques used to create miniaturized structures. Microelectromechanical systems (MEMS) are also described. The document outlines various microfabrication technologies and processes like silicon layering, LIGA, and micro-machining. It provides examples of applications in automotive, medical, chemical and other industries. Finally, the document introduces nano-technology and different types of nano-finishing processes.
Micromachining technologies for future productsvivatechijri
: Miniaturization is proceeding in various types of industrial products. Micromachining is the
foundation of the technology to realize such miniaturized products. A review of the literature, mostly of last
10years, that is enhancing our understanding of the mechanics of the rapidly growing field of micromachining
has been provided. The paper focuses only on methods of micromachining process along with applications of
major methods of micromachining.this paper gives you idea of current scenario of micromachining market of
world along with its benefits and challenges
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.
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A review on micro fabrication methods to produce investment patterns of microcasting
1. Journal of Natural Sciences Research www.iiste.org
ISSN 2224-3186 (Paper) ISSN 2225-0921 (Online)
Vol.1, No.2, 2011
A Review on Micro Fabrication Methods to Produce
Investment Patterns of Microcasting
Mohammad Mostafa Mohammadi1*
1. Department of Engineering, Abhar Branch, Islamic Azad Univercity, Abhar, Iran
* E-mail of the corresponding author: yahoommnet@gmail.com
Abstract
Microcasting is one of the key technologies enable the manufacture of small structures in the
micrometer range or of larger parts carrying microstructures by using a metal melt which is cast into a
microstructured mold. Microcasting, is generally identified with the investment casting process, which
is known as the lost-wax, lost-mold technique. A main step in micro investment casting is making
disposable patterns which have sufficient mechanical strength and dimensional accuracy. In this study
a review on available microfabrication methods to produce such patterns has been down and possible
processes have been compared in order to select the best process.
Keywords: micro investment casting, plastic pattern, micro manufacturing techniques
1. Introduction
Microcasting is one of the key technologies enable the manufacture of small structures in the micrometer
range or of larger parts carrying microstructures by using a metal melt which is cast into a microstructured
mold. This technology has been successfully applied for manufacturing of instruments for surgery and
dental devices, instruments for biotechnology and miniaturized devices for mechanical engineering.
Microcasting, is generally identified with the investment casting process, which is known as the lost-wax,
lost-mold technique (Baltes et al. 2005). Figure 1 shows the micro investment casting process steps. First
the plastic or wax pattern is made and embedded in a ceramic slip. After drying the ceramic mold is heated
and sintered and the pattern will be lost during this process due to melting and burning. Finally the
preheated ceramic mold is filled with metal melt by vacuum-pressure or centrifugal casting. After
solidification, the ceramic mold is mechanically removed without destroying or influencing the cast
surface. Depending on the casting alloy and the ceramic mold material, additional chemical cleaning
processes may be sometimes necessary. Finally, the single parts are separated from the runner system.
Mechanical removing of the ceramic mold after casting, offers the chance to produce metallic parts even
with undercuts. The key point in producing such parts is fabrication of pattern with undercut. Also pattern
fabrication technique directly influence on surface roughness and dimensional accuracy of the pattern
which are of importance in final surface quality and dimensional accuracy of the cast part. Common
approach in fabricating investment patterns is micro injection molding (Baltes et al, 2005; Baumeister et al.
2002, 2004; Qin 2010, Chuang et al. 2009; Thian et al. 2008; Rath et al. 2006), that has some disadvantages
and limitations. In this study other possible methods to fabricate these patterns has been introduced and
compared with each other.
2. Investment Casting Patterns
The type of pattern used also has a significant effect on the casting tolerances that can be obtained and
maintained. In general, final casting tolerances can be held within tighter limits as the rigidity and
durability of the pattern equipment increase. Traditional investment casting usually uses wax and
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2. Journal of Natural Sciences Research www.iiste.org
ISSN 2224-3186 (Paper) ISSN 2225-0921 (Online)
Vol.1, No.2, 2011
sometimes plastic, for pattern material and wax or plastic patterns are almost injection-molded. When wax
is used, the molds can be inexpensive, being made from a low-temperature alloy sprayed or cast around a
master-part pattern. The pattern is made with an allowance for shrinkage (Stefanescu et al. 1992).
In micro investment casting the patterns should guarantee a higher strength and are thus of advantage when
assembling microstructures thus in contrast to the wax patterns used there, microtechnology mostly works
with plastic patterns which have much higher mechanical strength. The patterns usually are made of
thermoplastic like PMMA or POM which shows much higher strength than wax made structures
(Baumeister et al. 2004). The improved mechanical properties permit easier handling and assembling of the
pattern during the manufacturing process. The feeding system can be made of wax. Figure 2 shows a
PMMA pattern with runner system made of wax, used for investment casting (Baltes et al. 2005).
2.1 Influence of Pattern on Surface Roughness and Dimensional Accuracy
By far the most significant factor influencing the dimensional accuracy of micro investment castings is the
dimension of pattern and shrinkage of the materials used as they change from the molten to solid state. The
wax or plastic pattern, the investment material, and the cast metal all exhibit this characteristic to some
degree. Like patterns for macrocasting, patterns for microcasting should be constructed according to the
well-known design rules for casting. Manufacturing method of the pattern should be able to produce the
pattern with required tolerance.
3. Microfabrication Methods to Produce PMMA Patterns
Today's technology gives various processes for microfabricating of polymer and plastic materials. To select
the suitable process, it is necessary to compare these processes based on availability, manufacturing aspects
and economical points of view.
3.1 Micro Mechanical Cutting
Micro-cutting is one of the key technologies to enable the realization of micro-products. Similarly to the
conventional cutting operation, in micro-cutting the surface of the workpiece is mechanically removed
using tools, but the depth of cut is normally at the level of a micrometer or less (Dornfeld et al. 2006). This
process brings many potentialities to the fabrication of miniature and micro-products components with
arbitrary geometry. The micro cutting process is particularly suitable for the manufacture of individual
personalized components rather than large batch sizes, which is largely indispensable for customized and
vibrant markets.
With the high level of machine accuracy of ultra-precision machine tools, good surface finish and form
accuracy can be achieved. Micro- cutting is also capable of fabricating 3D free-form surfaces. The high
machining speed of micro-cutting is another advantage over other micro manufacturing technologies.
Unlike micro-laser beam machining and lithographic techniques, it does not require a very expensive set-
up, which enables the fabrication of miniatures at an economically reasonable cost (Qin 2010).
Established methods of micromachining by turning, drilling, milling, and grinding have already been
applied to polymethylmetacrylate (PMMA) plastics (geough 2002).
3.1.1 Micro-turning
Various Swiss-type machine tools, ultra-precision lathes for diamond turning and miniature desktop
machines, are used to perform micro-turning operations on parts made of different materials like plastics.
The next application group of micro-turning operations with ultra precision mode makes it possible to
machine materials from a few microns to sub micron. Such a machining process is easily able to produce
mirror surfaces of less than 10 nm surface finish and form error of less than 1 nm on some diamond
turnable materials (geough 2002).
3.1.2 Micro-milling
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3. Journal of Natural Sciences Research www.iiste.org
ISSN 2224-3186 (Paper) ISSN 2225-0921 (Online)
Vol.1, No.2, 2011
Micro-milling is a classical form of tool-based micromachining, in which miniaturized milling cutters are
used to achieve the material removal in the form of chips. This micromachining technique is able to
produce three-dimensional high aspect ratio functional parts with high accuracy and surface quality. During
the stepping zone itself, micro-milling operation is suggested for a wide variety of medical and engineering
applications (Sooraj & Mathew 2002).
The micro-milling process is characterized by milling tools that are currently in the range from 10-100 pm
in diameter and made by the focused-ion beam machining process (Craig et al. 1996). the most usual
meaning of a micro-milling machine refers to ultra precision milling machines, with submicron accuracies,
that is, accuracies under 1 micron or less, usually one tenth of a micron. Machine tools capable of such
extreme accuracy may be applied to microscopic workpieces (micromachining), but they are more typically
applied to workpieces with features and details measurable in submicron increments or even in the
mesoscale.
The two main advantages of micro-milling in relation with other micro technologies are its apparent
similarity with conventional milling (which enables user to tackle the process from a position of in-depth
knowledge) and the fact that it enables intricate parts with 3D forms to be machined (molds, electrodes,
etc.) in a large range of materials (Lopez et al. 2009).
3.2 Laser Machining
Laser micromachining has been widely applied in the fabrication, production and manufacturing of Micro
Electro Mechanical Systems (MEMS). It uses photo thermal melting or ablation to fabricate a
microstructure (Neda et al. 2011).
In the production of micro-scaled products, laser ablation is able to generate structure sizes in the range of
10– 100 micro-meter, not only in metals and polymers like PMMA but also in hard and ultra-hard materials
such as tungsten carbide and ceramics. Especially for micro-machining, laser processes qualify for a wide
range of materials, from semiconductors in the field of micro-electronics, to hard materials such as tungsten
carbide for tool technology, to very weak and soft materials such as polymers for medical products. In
comparison to the classical technologies, laser processes are generally used for small and medium lot sizes
but with strongly increased material and geometric variability.
Using ultra-short pulsed lasers with durations of 10 ps in bursts of several pulses with a time spacing of 20
ns each and adapted pulse energies, the surface quality of metal micro-ablation has been increased
significantly and allows the production of tools and parts with Ra values of less than 0.5 mm.
Laser manufacturing of parts and tools can be performed without additional working tools in reasonable
times directly from the CADCAM system.
Material removal on polymers like PMMA can be obtained using low power lasers. Depending on the
interaction time, radiation intensity and polymer properties, the material is rapidly heated to become molten
and then burned or even vaporized. High energy density associated with the focused laser spot allows a
relevant resolution during cutting. This procedure can provide very small details or radii, which are difficult
to achieve if conventional milling process is used (Romoli et al. 2011). For this reason lasers are retained
to be flexible and precise “thermal tools” for the fast production of micro plastic patterns.
Unfortunately Distortion of the material is one of the negative effects of laser ablation, especially for
polymers. During laser cutting of polymers, bulges are formed mainly due to resolidification of molten
material in the working zone and temperature difference between the heat affected zone and the heat
unaffected zone. In order to prevent the creation of such defects it is necessary to choose laser machining
parameters like laser power accurately.
Commonly, PMMA are highly absorptive at the CO2 laser wavelength and transparent to the visible and
near-infrared spectra (Neda et al. 2011). Figure 3 shows a CO2 laser machine for fabrication PMMA micro
parts.
3.3 Micro Injection Molding
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4. Journal of Natural Sciences Research www.iiste.org
ISSN 2224-3186 (Paper) ISSN 2225-0921 (Online)
Vol.1, No.2, 2011
Microinjection molding (µIM) appears to be one of the most efficient processes for the large-scale
production of thermoplastic polymer microparts like patterns for micro investment casting. The micro-
injection molding process steps are the following (see Figure 4):
1. Plastic pellets are plasticized by the fixed extruder screw and fed into the metering chamber.
2. The shut-off valve closes in order to avoid backflow from the metering chamber.
3. After the set volume has been achieved, the plunger in the dosage barrel delivers the shot volume to the
injection barrel.
4. The injection plunger then pushes the melt into the mold.
5. Once the plunger injection movement is completed, a holding pressure may be applied to the melt. This
is achieved by a slight forward movement (maximum 1 mm) of the injection plunger.
The independent system for melting the polymer allows a limitation of the cycle times. The polymer flows
through small sized runners and gates using high speed and high pressure, which can favor its degradation.
The fabrication of high aspect ratio micro features can be achieved by using a mold temperature close to
the softening temperature of polymer, with structure sizes in the nanometer range (Giboz et al. 2007).
Nearly every commercially available thermoplastic – unfilled or filled – can be used for the microinjection
molding of plastic micro-components. In contrast to the injection molding of macroscopic parts, some
modifications of the process have to be developed to achieve complete mold filling and damage-free
demolding even for patterns down to the submicrometer regime (Baltes et al. 2005).
Mold inserts are required to produce microstructured plastic parts. Their micrometric dimensions and
tolerances require specific methods for the mold inserts realization, such as:
(i) LIGA based (lithography, electroplating, molding) technologies (LIGA, UV-LIGA, IB-
LIGA, EB-LIGA);
(ii) 3D micro machining regrouping micro electrical discharge machining (µEDM), micro
mechanical milling and electrochemical machining (ECM) using ultra-short pulses;
(iii) silicon wet etching (or silicon wet bulk machining);
(iv) deep reaction ion etching (DRIE);
(v) thick deep UV resists;
(vi) excimer and ultra-short pulse laser ablation
Compared with the µIM, the classical IM process uses ablation techniques of material, such as milling,
turning or EDM (Giboz et al. 2007).
3.4 Rapid prototyping
To reduce the product development time and reduce the cost of manufacturing, the new technology of rapid
prototyping (RP) has been developed, which offers the potential to completely revolutionize the process of
manufacture. This technology encompasses a group of manufacturing techniques, in which the shape of the
physical part is generated by adding the material layer-by-layer. Many of these techniques are based on
either the selective solidification of the liquid or bonding solid particles (Rosochowskia & Matuszakb
2000).
The most established and widely distributed technology is stereolithography with the direct layer-by-layer
transformation of computer-aided design data into a 3-D mold using the photopolymerisation of reactive
polymer resins with a focused UV beam (Volker Piotter & Thomas Hanemann 2011).
Micro-stereolithography (MicroSL) , is a novel micro-manufacturing process which builds the truly 3D
microstructures by solidifying the liquid monomer in a layer by layer fashion. The basic principle of
stereolithography is schematically shown in figure 5. A 3D solid model designed with CAD software is
sliced into a series of 2D layers with uniform thickness. The NC code generated from each sliced 2D file is
then executed to control a motorized x–y stage carrying a vat of UV curable solution. The focused scanning
UV beam is absorbed by an UV curable solution consisting of monomer and photoinitiators, leading to the
polymerization, i.e., conversion of the liquid monomer to the solid polymer. As a result, a polymer layer is
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formed according to each sliced 2D file. After one layer is solidified, the elevator moves downward and a
new layer of liquid resin can be solidified as the next layer. With the synchronized x–y scanning and the Z-
axis motion, the complicated 3D micro part is built in a layer by layer fashion. The MicroSL shares the
same principle with its macroscale counterpart, but in different dimensions. Submicron resolution of the x–
y–z translation stages and the fine UV beam spot enable precise fabrication of real 3D complex
microstructures (Zhang et al. 1999).
A promising three-dimensional microfabrication method that has recently attracted considerable attention is
based on two-photon polymerization with trashort laser pulses. When focused into the volume of a
photoresistive material like PMMA, the pulses initiate two photon polymerization via two photon
absorption and subsequent development (e.g. washing out the non illuminated regions) the polymerized
material reminds in the prescribe 3-D form. This allows fabrication of any computer generated structure by
direct laser recording into the volume of a photosensitive material. Figure 6 shows some micro components
fabricated via mentioned method. Because of the threshold behavior and non linear nature of the process, a
resolution beyond the diffraction limit can be realized by controlling the laser pulse energy and the number
of applied pulses. As a result the technique can provide much better resolution than micro-
stereolithography. The achieved resolution can be 100 nm or better (Ostendorf & Chichkov 2011).
5. Conclusion
As seen above, today's industry has provided various techniques to fabricate micro investment casting
patterns from PMMA. Comparison of these techniques based on important manufacturing criteria is
beneficial for selection of the best process to fabricate the patterns. Table 1 shows a comparison between
mentioned micromanufacturing techniques based on cost, aspect ratio, geometric freedom based on existing
of undercut, surface roughness and accuracy.
From table 1 it is obvious that in mass production the best process for pattern fabrication is microinjection
molding. A complete review of this technique can be found in (Giboz et al. 2007). For one-off and batch
production, microcutting, laser machining, micro steriolithography and two photon polymerization
technique respectively can be chosen. Complicate shapes with undercut may be producible only by
steriolithography and two photon polymerization.
References
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Bertsch, A., Lorenz, H. & Renaud, P. (1999), "3D microfabrication by combining microstereolithography
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Friedrich, C.R. & Vasile, J. (1996), "Development of the Micromilling Process for High Aspect Ratio
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Journal of micromechanics and microengineering 17, 96–109.
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Figure 1. Micro investment casting process, a plastic pattern, b embedded in ceramic slip, c hollow form, d
gold filled mold, e cast part
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Figure 2. Pattern with 15 injection-molded specimens fixed on a runner system
made of wax (Baltes et al. 2005).
Figure 3. Laser micro machining of PMMA (Neda et al. 2011).
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Figure 4. Schematic drawing of the injection molding process (Giboz et al. 2007).
Figure 5. The principle of stereolithography (Zhang et al. 1999).
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Figure 6. The SEM image shows a micro-scale dragon (left) and a movable windmill (right) fabricated by
two-photon polymerization (Ostendorf & Chichkov 2011).
Table 1. comparison between mentioned methods for fabrication PMMA patterns (Baltes et al. 2005;
Baumeister et al. 2002; Giboz et al. 2007; Ostendorf. A. & Chichkov, B.N. 2006; Choudhury, I.A, &
Shirley, S. 2010; Hansen,H.N, et al, 2011; Leea, K.S et al. 2008; Bertsch, A. et al 1999).
technique Workpiece accuracy Surface Geometrica Aspect cost
dimension roughness l freedom ratio
microcutting Higher than50 ~2 <100 nm low Medium medium
To Low
10-50
Laser machining Higher than ~ ~1 low low high
3 1-10
Micro injection Higher than Higher 10 nm to medium Medium Low to
molding 20 than 1 100 To low high
~20
MicroSL Higher than 1 ~5 ~5 high high high
Two photon Higher than 100nm to ~ 40nm high high high
polymerization nano meter
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