This document provides a review of porosity detection and its effect on the mechanical properties of additively manufactured components. It discusses common defects like gas porosity and lack of fusion in additive manufacturing and factors that affect these defects like process parameters and material properties. It also describes techniques for measuring porosity and defects, like X-ray computed tomography, ultrasonic testing and mass/volume measurements. Mechanical properties like tensile strength are found to depend on build orientation, with horizontally built specimens exhibiting higher strength than vertically built ones. Porosity is found to reduce mechanical properties and can be minimized by optimizing parameters like laser power and scan speed. Non-destructive evaluation techniques during manufacturing can detect defects and improve quality.
Experimental Behaviour of Steel Fiber Reinforced Concrete with partial Replac...ijtsrd
Concrete is generally used due to the abundance of uncooked material, low manufacturing and protection cost, excellence in compression, corrosion aspects, and versatility in forming more than a few shapes and its limitless structural purposes in aggregate with metal reinforcement. All these elements have contributed pressures to decrease cement consumption and to intensify lookup in exploring the probabilities of improving strength, sturdiness and corrosion discount via the use of pozzolonas as supplementary cementing materials. Fibre bolstered concrete FRC is a fibre reinforcing cementitious concrete composite, and by way of including discrete brief fibres randomly in concrete it famous many appreciably multiplied engineering residences It is manufactured from kaolin which makes the concrete extra long lasting and ecofriendly. In the current investigation mechanical residences of concrete containing each Fly ash and Metakaolin at a number of combos are studied. For the a range of mixtures of Fly ash and Metakaolin, cubes cylindrical and prism specimens are casted with 1 of fibres and the compression strength, break up tensile energy and flexural energy take a look at consequences are got and in contrast with the traditional combine having 1 fibres. It is thereby counseled that utilization of these cementitious substances in concrete will decrease the requirement for cement thereby marching in the direction of green construction. M. Sankaran | Dr. M. Gunasekaran | M. Loganathan "Experimental Behaviour of Steel Fiber Reinforced Concrete with partial Replacement of Fly Ash & Metakaolin" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-4 | Issue-5 , August 2020, URL: https://www.ijtsrd.com/papers/ijtsrd33163.pdf Paper Url :https://www.ijtsrd.com/engineering/civil-engineering/33163/experimental-behaviour-of-steel-fiber-reinforced-concrete-with-partial-replacement-of-fly-ash-and-metakaolin/m-sankaran
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.
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
Analyzing Adhesion of Epoxy/Steel Interlayer in Scratch TestIJERA Editor
The aim of this paper is to investigate use of an experimental technique to determine which parameters effects
on the interfacial durability performance of adhesive on the metallic adherends as zinc plated mild steel (S235)
by using Taguchi method. The experimental layout has been used four scratch force parameters using the L16
(41x23) orthogonal array. The statistical methods of signal to noise ratio (SNR) and the analysis of variance
(ANOVA) were applied to examine effects of surface treatment, adhesive type, blade angle and thickness on
scratch force and scratch energy. Besides, the surface analysis was carried out the morphological modifications
as well as to perform elemental analyses of the pre-treated surfaces. Results of this study indicate that the
thickness and surface treatment are main parameters influencing scratch force (by 52.4% and 19.9%) and
scratch energy (by 44.0 % and 25.6%), respectively.
Experimental and Analytical Investigation of Drilling of Sandwich Composites:...IOSR Journals
A composite material is made out of a mixture or a combination of two or more distinctly differing
materials which are insoluble in each other and differ in form or chemical composition. The technological and
commercial interest in composite material lies in their superior properties of strength-to-weight, stiffness-toweight,
fatigue and thermal expansion compared to metals. Extensive use of composite in application such as
rockets, satellites, missiles, light combat aircraft, advanced light helicopter and trainer air craft has shown that
India is on par with the advanced countries in the development and use of composites in this area.
Drilling is probably the most important conventional mechanical process and it is the most widely used
machining operation. Prediction of cutting forces for any set of cutting parameters is essential in optimal design
and manufacturing of products. It has been predicted that most of the problem associated with hole making
operation, such as drilling, can be attributed to the force generated during cutting operation. Many
developments and experiments are going on drilling of Sandwich composite for damage free drilling along with
the quality of the hole and the effect of tool geometry and tool material.
This paper aims at the comprehensive analytical and experimental investigation work done on the
composites material. The conclusion of the paper discusses the development and outlines the trends for the
research in this field.
Experimental Behaviour of Steel Fiber Reinforced Concrete with partial Replac...ijtsrd
Concrete is generally used due to the abundance of uncooked material, low manufacturing and protection cost, excellence in compression, corrosion aspects, and versatility in forming more than a few shapes and its limitless structural purposes in aggregate with metal reinforcement. All these elements have contributed pressures to decrease cement consumption and to intensify lookup in exploring the probabilities of improving strength, sturdiness and corrosion discount via the use of pozzolonas as supplementary cementing materials. Fibre bolstered concrete FRC is a fibre reinforcing cementitious concrete composite, and by way of including discrete brief fibres randomly in concrete it famous many appreciably multiplied engineering residences It is manufactured from kaolin which makes the concrete extra long lasting and ecofriendly. In the current investigation mechanical residences of concrete containing each Fly ash and Metakaolin at a number of combos are studied. For the a range of mixtures of Fly ash and Metakaolin, cubes cylindrical and prism specimens are casted with 1 of fibres and the compression strength, break up tensile energy and flexural energy take a look at consequences are got and in contrast with the traditional combine having 1 fibres. It is thereby counseled that utilization of these cementitious substances in concrete will decrease the requirement for cement thereby marching in the direction of green construction. M. Sankaran | Dr. M. Gunasekaran | M. Loganathan "Experimental Behaviour of Steel Fiber Reinforced Concrete with partial Replacement of Fly Ash & Metakaolin" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-4 | Issue-5 , August 2020, URL: https://www.ijtsrd.com/papers/ijtsrd33163.pdf Paper Url :https://www.ijtsrd.com/engineering/civil-engineering/33163/experimental-behaviour-of-steel-fiber-reinforced-concrete-with-partial-replacement-of-fly-ash-and-metakaolin/m-sankaran
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.
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
Analyzing Adhesion of Epoxy/Steel Interlayer in Scratch TestIJERA Editor
The aim of this paper is to investigate use of an experimental technique to determine which parameters effects
on the interfacial durability performance of adhesive on the metallic adherends as zinc plated mild steel (S235)
by using Taguchi method. The experimental layout has been used four scratch force parameters using the L16
(41x23) orthogonal array. The statistical methods of signal to noise ratio (SNR) and the analysis of variance
(ANOVA) were applied to examine effects of surface treatment, adhesive type, blade angle and thickness on
scratch force and scratch energy. Besides, the surface analysis was carried out the morphological modifications
as well as to perform elemental analyses of the pre-treated surfaces. Results of this study indicate that the
thickness and surface treatment are main parameters influencing scratch force (by 52.4% and 19.9%) and
scratch energy (by 44.0 % and 25.6%), respectively.
Experimental and Analytical Investigation of Drilling of Sandwich Composites:...IOSR Journals
A composite material is made out of a mixture or a combination of two or more distinctly differing
materials which are insoluble in each other and differ in form or chemical composition. The technological and
commercial interest in composite material lies in their superior properties of strength-to-weight, stiffness-toweight,
fatigue and thermal expansion compared to metals. Extensive use of composite in application such as
rockets, satellites, missiles, light combat aircraft, advanced light helicopter and trainer air craft has shown that
India is on par with the advanced countries in the development and use of composites in this area.
Drilling is probably the most important conventional mechanical process and it is the most widely used
machining operation. Prediction of cutting forces for any set of cutting parameters is essential in optimal design
and manufacturing of products. It has been predicted that most of the problem associated with hole making
operation, such as drilling, can be attributed to the force generated during cutting operation. Many
developments and experiments are going on drilling of Sandwich composite for damage free drilling along with
the quality of the hole and the effect of tool geometry and tool material.
This paper aims at the comprehensive analytical and experimental investigation work done on the
composites material. The conclusion of the paper discusses the development and outlines the trends for the
research in this field.
6.a review on wear behaviour of clutch plate made of peek composite materialEditorJST
The conventional clutch plate made of carbon fiber and ceramic mixture of copper, iron, tin bronze,
silicon dioxide, and/or graphite, typical alloy is a lamellar pearlitic gray iron like G11H20b of which, it can be
replaced by developing of new materials for reducing the wear rate of the clutch plate the materials chosen is
Poly Ether Ether Ketone (PEEK) based composites mixed with silicon carbide powder shows better results in
which it can be manufactured by the injection moulding process and it is tested in Friction and wear experiment
wear run under constant temperature in a pin-on-disc arrangement, PEEK and its composites used in this
investigated the friction coefficient decreases with the increasing load on PEEK. The composite showed a very
low friction coefficient and wear rate increase in the normal applied load sliding distance decreases wear rate.
Further the wear and friction behaviour decreases with increases the gradually by addition of fillers.
Effect of Temperature on Wear Rate of Si-Epoxy- Eglass Polymer composite Mate...IDES Editor
With the increase use of polymer composites in
erosive work environment, it has become extremely important
to investigate their erosion characteristics. The hybrid
composite consisting of a Epoxy resin reinforced with Eglass
fiber and Si particles was developed. The effect of temperature
on wear rate applied to Si – Epoxy – Eglass polymer composite
has been studied. It has been found that the wear rate increases
as the temperature of carrier media (air) is increased.
Temperature of carrier media is one of the significant factor
influencing the erosion wear. The results were compared with
the plain epoxy composite material. Micrographs of eroded
surface are also presented to study the wear rate and Wear
behavior of composite.
Taguchi analysis of single layer CrN coatings on AISI 304 Stainless Steel to ...IJAEMSJORNAL
The purpose of present study was to investigate the erosive corrosive wear behavior of single layer (CrN) coatings on AISI 304 Stainless Steel samples with varying coating thickness (0-200 nm) in the range of 50 nm. The slurry jet erosive test was conducted on Slurry Jet Erosion Tester in saline slurry (3.5wt% salt) under the different working conditions with varying impact velocity (10-25 m/s), impingement angle (30°-75°) and erodent discharge (160-280 gm/min). Taguchi analysis was applied to find optimum parameters for the minimization of erosion rate of various coated and uncoated samples. The results of Taguchi experiments also indicated that among all the factors, impact velocity became least significant when samples were coated with CrN whereas it was most significant for uncoated samples. Coating thickness was the second most significant factor in the case of CrN coated samples. PVD- CrN coatings reduced the wear rate by nearly 2 times.
Study on Design, Fabrication and Properties of Biomedical Porous Titanium - C...CrimsonPublishersRDMS
Study on Design, Fabrication and Properties of Biomedical Porous Titanium by Guangsheng Xu* in Crimson Publishers: Peer Reviewed Material Science Journals
In manufacturing, many products need to undergo increasing customisation, and a shortening of the manufacturing cycle time. This makes the time needed to produce prototypes one of the most important contributors to product development cycles. Rapid Prototyping (RP) offers the user the ability to optimise part design in order to meet customer requirements with few manufacturing restrictions. One of the most common RP processes is Laser Sintering (LS). A problem with LS is that sometimes the surface of the parts produced displays a texture similar to that of the skin of an orange (the so-called orange peel texture). This problem must be addressed before the technology can gain wider acceptance. The main aim of this research is to develop a methodology of controlling the input material properties that will ensure consistent and good quality of the fabricated parts. From the experiment, it was found that PA12 powder with high melt flow rate, low melting temperature, low glass transition temperature and low degree of crystallization temperature could improve the sintering process to produce a good Laser Sintering (LS) parts with lower shrinkage rate. The powder which has higher melt viscosity and lower melting heat becomes liquid more easily and therefore flows better during the sintering process due to a shorter chain molecular structure. The results of experimental work indicate that the melt viscosity, and part surface finish are correlated.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Testing of Already Existing and Developing New Compaction Equations during C...IJMER
Powder Metallurgy (P/M) processing of materials to produce conventional P/M parts
involve the compaction of the pre-determined mass of individual elemental, mixed elemental metal
powders or alloy powders and or composite powders into green compacts and sintering them under
reducing atmosphere and or under other protective coatings, thus, after sintering producing
products after mild machining operations. Therefore, compaction represents one of the most
important stages in the production of engineering components using the P/M route. However, the
physical properties such as density and the stress distribution in the green compacts are determined
not only by the properties of the constituents of the powder or the powder blend, but, also by the
pressing modes and schedules. Thus, the present investigation pertains to generate experimental
data on the compaction behaviour of Fe-1.05% graphitesystems with two different iron particle size
ranges and two different powder masses in order to highlight the various aspects of compaction and
also testing out the already existing compaction equations and search for the new ones. Powder
blends of two different iron powder particle size ranges, namely, -106+53µm and -150+106µm
respectively were blended with the required amount of graphite powder of 3 – 5 µm sizes for a
period of 32 hours. Compaction studies have been carried out for two different amounts of both
powder blends. The two amounts taken were 65g and 85g respectively. However, the main attempt
was made to record the load and the corresponding heights and the top punch displacements for
every two tons (0.02MN) of load which was applied in the steps of 0.02MN. Various equations for
compaction were attempted empirically and the already existing ones were also tested. Critical
analysis of the experimental data and the calculated parameters have resulted into several
compaction equations which were arrived at empirically. The regression coefficient ‘R2
’ in each
case where compactions equations were empirically obtained was in very much close proximity to
unity. However, it has been also confirmed that the data of the present investigation were well
taken up by the earlier compactions equations, thus, validating them comprehensively.
PERFORMANCE COMPARISON OF FLYASH AND WOLLASTONITE MICRO-FIBER IN OBTAINING SE...IAEME Publication
Present study aims to find out the role of flyash and Wollastonite micro-fiber in
obtaining cheap self compacting concrete for pavements. Workability tests (Abrams
flow, V Funnel and J Ring test) have been performed which find out the flow,
passability and segregation resistance of trial mixes. Load transfer efficiency test has
also been performed with successful mixes on a pavement prototype. It was observed,
that both flyash and wollstonite micro-fiber when used alone can’t yield self
compaction, but with microsilica content upto 5% they do so, provided their content is
lesser than 20% each, respectively. Wollastonite reinforced concrete has two times
better load transfer efficiency with respect to normal concrete.
Study of an alternate manufacturing process of piston pineSAT Journals
Abstract In automobile industry development in technology has been increases significantly and so as the performance of an engine. In reciprocating internal combustion engine major parts having sliding motion among their parts and failure of any part in dynamic stage will cause major impact on engine such as failure of an engine. Piston pin play a vital role in the reciprocating internal combustion engine. Failure of piston pin will result in failure of engine. It has been investigated that fatigue failureis one of the major reason of failure of a piston pin. Piston pin are subjected to multiaxial stresses due to which crack initiation and propagation from the surface decreases intensely the fatigue strength of surface and fatigue fracture occurredso every effort has to be made towards improvement in sliding properties of piston pin which will reduce wear resistance of metal surface and ultimately increases fatigue life of piston pin without sacrificing any of the major property requirements of the substrate material. Literature shows that phosphating is one of the surface coating method which will improve friction properties and wear properties thus increases fatigue life. In this work, an effort is to suggest phosphate surface coating on a piston pin as an alternative to conventional surface coating. The investigation effect of phosphating surface coating on piston pin of different material is studied by using design of experiments. Key Words: Design of Experiment, Fatigue Strength, Piston pin, Phosphating
6.a review on wear behaviour of clutch plate made of peek composite materialEditorJST
The conventional clutch plate made of carbon fiber and ceramic mixture of copper, iron, tin bronze,
silicon dioxide, and/or graphite, typical alloy is a lamellar pearlitic gray iron like G11H20b of which, it can be
replaced by developing of new materials for reducing the wear rate of the clutch plate the materials chosen is
Poly Ether Ether Ketone (PEEK) based composites mixed with silicon carbide powder shows better results in
which it can be manufactured by the injection moulding process and it is tested in Friction and wear experiment
wear run under constant temperature in a pin-on-disc arrangement, PEEK and its composites used in this
investigated the friction coefficient decreases with the increasing load on PEEK. The composite showed a very
low friction coefficient and wear rate increase in the normal applied load sliding distance decreases wear rate.
Further the wear and friction behaviour decreases with increases the gradually by addition of fillers.
Effect of Temperature on Wear Rate of Si-Epoxy- Eglass Polymer composite Mate...IDES Editor
With the increase use of polymer composites in
erosive work environment, it has become extremely important
to investigate their erosion characteristics. The hybrid
composite consisting of a Epoxy resin reinforced with Eglass
fiber and Si particles was developed. The effect of temperature
on wear rate applied to Si – Epoxy – Eglass polymer composite
has been studied. It has been found that the wear rate increases
as the temperature of carrier media (air) is increased.
Temperature of carrier media is one of the significant factor
influencing the erosion wear. The results were compared with
the plain epoxy composite material. Micrographs of eroded
surface are also presented to study the wear rate and Wear
behavior of composite.
Taguchi analysis of single layer CrN coatings on AISI 304 Stainless Steel to ...IJAEMSJORNAL
The purpose of present study was to investigate the erosive corrosive wear behavior of single layer (CrN) coatings on AISI 304 Stainless Steel samples with varying coating thickness (0-200 nm) in the range of 50 nm. The slurry jet erosive test was conducted on Slurry Jet Erosion Tester in saline slurry (3.5wt% salt) under the different working conditions with varying impact velocity (10-25 m/s), impingement angle (30°-75°) and erodent discharge (160-280 gm/min). Taguchi analysis was applied to find optimum parameters for the minimization of erosion rate of various coated and uncoated samples. The results of Taguchi experiments also indicated that among all the factors, impact velocity became least significant when samples were coated with CrN whereas it was most significant for uncoated samples. Coating thickness was the second most significant factor in the case of CrN coated samples. PVD- CrN coatings reduced the wear rate by nearly 2 times.
Study on Design, Fabrication and Properties of Biomedical Porous Titanium - C...CrimsonPublishersRDMS
Study on Design, Fabrication and Properties of Biomedical Porous Titanium by Guangsheng Xu* in Crimson Publishers: Peer Reviewed Material Science Journals
In manufacturing, many products need to undergo increasing customisation, and a shortening of the manufacturing cycle time. This makes the time needed to produce prototypes one of the most important contributors to product development cycles. Rapid Prototyping (RP) offers the user the ability to optimise part design in order to meet customer requirements with few manufacturing restrictions. One of the most common RP processes is Laser Sintering (LS). A problem with LS is that sometimes the surface of the parts produced displays a texture similar to that of the skin of an orange (the so-called orange peel texture). This problem must be addressed before the technology can gain wider acceptance. The main aim of this research is to develop a methodology of controlling the input material properties that will ensure consistent and good quality of the fabricated parts. From the experiment, it was found that PA12 powder with high melt flow rate, low melting temperature, low glass transition temperature and low degree of crystallization temperature could improve the sintering process to produce a good Laser Sintering (LS) parts with lower shrinkage rate. The powder which has higher melt viscosity and lower melting heat becomes liquid more easily and therefore flows better during the sintering process due to a shorter chain molecular structure. The results of experimental work indicate that the melt viscosity, and part surface finish are correlated.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Testing of Already Existing and Developing New Compaction Equations during C...IJMER
Powder Metallurgy (P/M) processing of materials to produce conventional P/M parts
involve the compaction of the pre-determined mass of individual elemental, mixed elemental metal
powders or alloy powders and or composite powders into green compacts and sintering them under
reducing atmosphere and or under other protective coatings, thus, after sintering producing
products after mild machining operations. Therefore, compaction represents one of the most
important stages in the production of engineering components using the P/M route. However, the
physical properties such as density and the stress distribution in the green compacts are determined
not only by the properties of the constituents of the powder or the powder blend, but, also by the
pressing modes and schedules. Thus, the present investigation pertains to generate experimental
data on the compaction behaviour of Fe-1.05% graphitesystems with two different iron particle size
ranges and two different powder masses in order to highlight the various aspects of compaction and
also testing out the already existing compaction equations and search for the new ones. Powder
blends of two different iron powder particle size ranges, namely, -106+53µm and -150+106µm
respectively were blended with the required amount of graphite powder of 3 – 5 µm sizes for a
period of 32 hours. Compaction studies have been carried out for two different amounts of both
powder blends. The two amounts taken were 65g and 85g respectively. However, the main attempt
was made to record the load and the corresponding heights and the top punch displacements for
every two tons (0.02MN) of load which was applied in the steps of 0.02MN. Various equations for
compaction were attempted empirically and the already existing ones were also tested. Critical
analysis of the experimental data and the calculated parameters have resulted into several
compaction equations which were arrived at empirically. The regression coefficient ‘R2
’ in each
case where compactions equations were empirically obtained was in very much close proximity to
unity. However, it has been also confirmed that the data of the present investigation were well
taken up by the earlier compactions equations, thus, validating them comprehensively.
PERFORMANCE COMPARISON OF FLYASH AND WOLLASTONITE MICRO-FIBER IN OBTAINING SE...IAEME Publication
Present study aims to find out the role of flyash and Wollastonite micro-fiber in
obtaining cheap self compacting concrete for pavements. Workability tests (Abrams
flow, V Funnel and J Ring test) have been performed which find out the flow,
passability and segregation resistance of trial mixes. Load transfer efficiency test has
also been performed with successful mixes on a pavement prototype. It was observed,
that both flyash and wollstonite micro-fiber when used alone can’t yield self
compaction, but with microsilica content upto 5% they do so, provided their content is
lesser than 20% each, respectively. Wollastonite reinforced concrete has two times
better load transfer efficiency with respect to normal concrete.
Study of an alternate manufacturing process of piston pineSAT Journals
Abstract In automobile industry development in technology has been increases significantly and so as the performance of an engine. In reciprocating internal combustion engine major parts having sliding motion among their parts and failure of any part in dynamic stage will cause major impact on engine such as failure of an engine. Piston pin play a vital role in the reciprocating internal combustion engine. Failure of piston pin will result in failure of engine. It has been investigated that fatigue failureis one of the major reason of failure of a piston pin. Piston pin are subjected to multiaxial stresses due to which crack initiation and propagation from the surface decreases intensely the fatigue strength of surface and fatigue fracture occurredso every effort has to be made towards improvement in sliding properties of piston pin which will reduce wear resistance of metal surface and ultimately increases fatigue life of piston pin without sacrificing any of the major property requirements of the substrate material. Literature shows that phosphating is one of the surface coating method which will improve friction properties and wear properties thus increases fatigue life. In this work, an effort is to suggest phosphate surface coating on a piston pin as an alternative to conventional surface coating. The investigation effect of phosphating surface coating on piston pin of different material is studied by using design of experiments. Key Words: Design of Experiment, Fatigue Strength, Piston pin, Phosphating
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
An Overview of Clearance Optimization in Sheet Metal Blanking ProcessIJMER
Abstract: This document prescribes a model investigation the effect of potential parameters influencing the blanking
process and their interaction. The blanking process optimization carried out by using Design of Experiment (DOE), Finite
Element Method (FEM) with ANSYS Package, Simulation with ABAQUS-Explicit software, Blank soft Software and Neural
Network Simulation in order to achieve the intended model objectives.
Keywords: Blanking Process, DOE, FEM, Optimum Clearance and Simulation.
COMPARATIVE STUDY OF EXPERIMENTAL AND ANALYTICAL RESULTS OF GEO POLYMER CON...IAEME Publication
Geo polymer concrete is a recently developed construction material which is environment friendly and perhaps best alternative to conventional concrete. In the present scenario, where global warming is a big issue due to Co2 emissions, no cement concrete like Geo Polymer Concrete is the big boon for construction industry. The research work carried out on Geo Polymer Concrete and documented in the present paper is a step forward in the direction to encourage the development of Geo Polymer Concrete for its wide application in construction industry. The present paper describes experimental work and analytical work pertaining to Finite Element Analysis using ANSYS software to simulate the flexural behavior of Reinforced Geo Polymer Concrete Beams. The alkaline solution used for present study was the combination of sodium silicate and sodium hydroxide solution with the varying ratio of 2.50. NaoH solids with 97 - 98% purity is purchased from commercial source and mixed with water to make solution with a concentration of 16 molarity.
Machining is one of the unavoidable operation after the processing of any type of
material. Because of the advancement in the technology and innovation in the materials
area, the composite materials are replacing and occupying the traditional materials
market rapidly. Among these composite materials, the Fiber Reinforced Polymer (FRP)
composite materials are found to be technically and structurally competitive and are
widely used in a number of engineering industrial applications. The machining of these
composites is found to be a complex phenomenon due to the influence of a number of
machining and material parameters related to machining. Since drilling is the most
frequently applied machining operation on composites, many research works were done
on the drilling of composites, which resulted in numerous parameters that have influence
on the drilling operation, impact on work material and cutting tool damage, cost of
machining, material removal rate etc. So, at the background, it was thought to have a
review on the issues related to drilling on the composite materials, which could help the
manufacturing sectors and researchers in order to enhance the productivity. Thus the aim
of this technical paper is to provide a detailed study of various issues related to drilling
of FRP composite materials. This paper also comprehensively addresses the success and
the failures of drilling operations, the factors associated with the drilling operation, their
impact on the various output parameters. In addition, this review paper also discusses
about the influences of a number of machining parameters and their influence on
machining.
Study of Concrete Properties under Acid Attacksijtsrd
Acidic attack on concrete imparts a unique set of damage mechanisms and manifestations compared to other durability issues of concrete. Sulfuric acid attack limits the service life of concrete elements and, thus, results in increased expenditures for the repair or in some cases replacement of the whole structure. To date, there is lack of standardized tests for specifically evaluating the resistance of concrete to sulfuric acid attack, which has caused great variability, for example in terms of solution concentration, pH level control, etc., among previous studies in this area. Accordingly, there are conflicting data about the role of key constituents of concrete e.g. supplementary cementitious materials SCMs , and uncertainty about building codes' stipulations for concrete exposed to sulfuric acid. Hence, the first objective of this thesis was to assess the behaviour of the same concretes, prepared with single and blended binders, to incremental levels mild, severe and very severe of sulfuric acid solutions over 36 weeks. The test variables included the type of cement general use GU or portland limestone cement PLC and SCMs fly ash, silica fume and nano silica . The severe 1 , pH of 1 and very severe aggression 2.5 , pH of 0.5 phases caused mass loss of all specimens, with the latter phase providing clear distinction among the performance of concrete mixtures. The results showed that the penetrability of concrete was not a controlling factor, under severe and very severe damage by sulfuric acid attack, whereas the chemical vulnerability of the binder was the dominant factor. Mixtures prepared from PLC performed better than that of counterparts made from GU. While the quaternary mixtures comprising GU or PLC, fly ash, silica fume and nano silica showed the highest mass losses after 36 weeks, binary mixtures incorporating GU or PLC with fly ash had the lowest mass losses. S. Durgasravanthi | M. Krishna Kumar "Study of Concrete Properties under Acid Attacks" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-3 | Issue-5 , August 2019, URL: https://www.ijtsrd.com/papers/ijtsrd26392.pdfPaper URL: https://www.ijtsrd.com/engineering/structural-engineering/26392/study-of-concrete-properties-under-acid-attacks/s-durgasravanthi
Investigation on Strength and Light Transmittance of Translucent concrete wit...
AdditiveManufacturingResearch_Report
1. 1
Review on the Progress of Porosity Detection and
its Effect on Mechanical Properties of Additive
Manufacturing Components
Mohammad Rashid Mohammad Shoaib Instructor Dr. Leonard Bond
Aerospace Engineering
Iowa State University
2. 2
ABSTRACT
Additive Manufacturing (AM) has seen a risen interest, both in the consumer sector as well as in
industrial applications. However, AM industry is also facing several technical challenges. This report
provides a brief review on the defects in Additive Manufactured components, factors affecting these
defects, their measurements techniques using in-situ NDE and mechanical properties. The aim of this
review is to identify and summarize the factors affecting the fabrication of AM parts and its allowables.
3. 3
Table of Contents
1. Introduction ……………………………………………………………………………………. 1
2. Defects In Additive Manufacturing ……………………………………………………… 1
Porosity ……………………………………………………………………………………. 1
Gas Porosity ……………………………………………………………………………. 1
Lack of fusion ……………………………………………………………………………. 2
3. Factors ……………………………………………………………………………………………... 4
4. Measurements and Properties …………………………………………………………… 5
5. Conclusion ………………………………………………………………………………………. 19
4. 4
1. Introduction
Additive manufacturing (AM) is a process of fabricating parts or objects by joining and building
up material layer by layer from a computerized three dimensional model data. The AM process
always starts with a CAD model, which then is converted into a STL file. Here it is sliced into a certain
number of layers depending on desired precision and then exported to the AM machine. AM makes
effective and efficient use of raw materials, producing less waste than its counterpart, subtractive
manufacturing, while producing satisfactory accuracy in finished parts. AM has ability to quickly
produce parts with complex geometry which is difficult to achieve using conventional
manufacturing. It is also considered a sustainable technology due to its low energy consumption
during the manufacturing process. Some of the advantages of additive manufacturing when
compared to conventional manufacturing are a shorter time to market, use of inexpensive
materials, high production rate, versatility, accuracy and an ability to produce unique features.
2. Defects in Additive Manufacturing
In Additive Manufacturing, powder is melted within the melt pool and solidified to form a deposited
track. These deposited tracks may contain porosities or cracks which affect the functionality of the part.
When these defects go undetected, they may cause failure of the part. These defects act as stress
concentrators that compromise the components quality. Common defects in AM components are gas
porosity, lack of fusion and cracking. It is important to understand the effects of these defects on the
components to facilitate a better understanding of manufacturing and repair of AM parts.
Porosity
Porosity is the most common defect found in components produced through AM. It can be
divided into two categories: gas porosity and lack of fusion (LOF). Liujinhui et al (2011) discussed that
the porosity is a result of fluid, fusion, welding, separation and balling of metal in the melt pool and its
creation is complex. Gu et al (2013) also pointed out two types of porosity formation mechanisms: the
balling phenomenon and high thermal stresses.
Gas Porosity
Gas Porosity is porosity caused by gasses that get entrapped in the AM part and typically have
smooth spherical morphology. Bauereiß et al (2014) defined gas porosity as a result of gas entrapped
within gas atomized powder particle. These are common in AM parts and growth over the layer has
been experimentally observed. The porosity as seen in Figure1 and 2 can be decreased by choosing
proper process parameters and material parameters which will be discussed in later sections but could
not be eliminated.
GKL Ng et al (2009) found that gas porosity is mostly due to an overly high powder flow rate
which traps the shielding gas within the melt pool and also lowers the specific energy of the melt pool.
In AM mostly gas atomized powder is used, this increasing the probability of entrapped gas within the
powder particles.
5. 5
Lack of Fusion
Lack of fusion (LOF) is a material discontinuity at the melt layer boundary in which two
faces become separated and form porosity due to lack of fusion. Lack of fusion are irregularly
shaped and often contain trapped and un-melted powder particles.
GKL Ng et al (2009) used gas atomized Inconel 718 powder and concluded that porosity
due to lack of fusion is because of the inability of the melt pool to melt the powder particles due
to low specific energy.
Olakanmi et al (2015) informed that lack of fusion defects are usually found along the
layer boundaries and are irregularly shaped, often containing un-melted powder. They
attributed lack of fusion to insufficient dissipation of the laser energy density into the powder
layer thickness.
Liu Qianchu et al (2014) explained a similar reason for lack of fusion i.e. insufficient
energy to the melt pool. They divided lack of fusion into three categories (a) Separated surface
with un-melted powder, (b) Separated surface without un-melted powder and (c) Narrow and
long shaped with un-melted powder. Type (a) and type (b) were present in vertical built
specimen and type (c) was observed in horizontal built specimen. Bauereiß et al (2014) found
similar defects to LOF and they concluded that it was possible to eliminate these defects by
increasing the power of the beam. According to the study of Liu Qianchu et al (2014) LOF defects
have an influence on the fatigue life of the specimen. Defects closer to the surface affected
fatigue life less compared to the defect that were deeper or far from the surfaces.
LOF can be corrected by adjusting external factors such as scan speed, laser power, layer
thickness etc.
6. 6
Bauereiß et al. (2014) explained the formation of large cavities in the AM products. According to
their study combining of the melt pool is much faster than the melting of single powder particle, which
means that the powder particle starts blending even before it is melted. Due to this behavior, powder
particles combine with the first liquid or solid surface they come into contact with and form isolated
drops of liquid. The direction of this liquid is not downward instead its lateral and is in spherical shape.
Because of this, the energy from the beam does not reach the previous layer and particles cannot fuse
and this causes large cavities for several layers as shown in Figure 4.
7. 7
3. Influencing Factors
The quality of the AM manufactured part is highly dependent on many interrelated factors such as
process parameters, powder characteristics and surrounding conditions. The factors affecting the AM
process can be divided into two categories process parameters and material parameters. Process
parameters are the inputs and primarily determine the rate of energy delivered to the surface of the
powder as well as how energy interacts with material. Process parameters be controlled to achieve
variations in the properties of these components. Rombouts et al (2006) named following as process
parameters: laser power, scan speed, layer thickness, spacing of scan lines and powder feed rate.
Material parameters such as powder size and distribution are decided at the beginning of the
manufacturing process.
Simchi (2006) pointed out that sintered density of AM component depends on powder
characteristics, fabrication parameters, layer thickness and scan line spacing. Higher laser power results
in higher density and increasing the thickness of layer decreases the density. They concluded that
density seems to be linearly proportional to the ratio of laser to the scan rate on a semi log scale. They
also analyzed the influences on the porosity from oxygen content, shape, size and its distribution. The
conclusion is that high density is obtained when the powder particles are fine and oxygen content is low,
assuming proper parameters.
Ng et al (2009) concluded that LOF and gas porosity were affected by different factors. LOF was
largely governed by specific energy provided to the melt pool whereas gas porosity was believed to
originate from gas entrapped in the powder. Gas porosity was harder to eliminate than the LOF and can
be as high as 0.7%. LOF was affected by powder feed rate, traverse speed and track overlap. LOF
reduced with the increase in transverse speed. This was an unexpected result because they thought this
should have increased the LOF, as increasing the transverse speed decreases the specific energy and
therefore increases LOF. LOF increased as the powder feed rate was increased. Increasing the track
overlap did not have a significant effect. Gas porosity was found to be dependent on process
parameters and pool dynamics. The porosity measured average around 0.2%. It was deduced that gas
porosity increases with powder feed rate and shielding gas. At low powder feed rate and low laser
power, gas porosity increased significantly.
Meier and Haberland (2008) concluded that an increase in laser power
results in a decrease in porosity. With effective laser power of 90 Watts, a
relative density of 99% is realistic. (Figure 5p). With decreasing scan speed and
hatch distances (i.e., increasing input energy) the relative density increases.
This means that a higher density is achieved by the input of higher energy. They
pointed out that the pores appeared lattice like when the hatch distance was
too large and when the scanning speed was large, the pores were irregular.
They also investigated the effect of scanning speed on the horizontal surface
and vertical walls and concluded that an increase in scanning speed initiated
fragmentation first in vertical walls, and then horizontal.
8. 8
4. Measurements Techniques And Properties
There is a real need to monitor manufacturing of AM parts layer by layer while they are being
manufactured to detect defects and reduce cost. This can be done by different measurement tools and
techniques. These techniques are useful in giving data needed for optimizing the process and learning
which parameter needs to be controlled and monitor to ensure high quality of the component.
Bond et al (2014) provided an overview of current non-destructive evaluation (NDE) tools and new
approach to total quality management for the characterization of materials from metal powder to
finished parts. They concluded that micro computed tomography (CT) is a very rapid and cost effective
way to obtain structural information at very early stages. From a CT scan, size distribution, shapes and
internal features of the particle such as porosity can be determined quickly. They also applied a high
resolution digital X-ray radiography (Figure 6) to metal powder in order to inspect porosity and grain size
distribution. According to them radiography can be used with image processing to assess uniformity of
particle’s shape, size and distribution. Ultrasonic imaging was another tool Bond et al (2014) explained
that can be used to measure porosity, elastic moduli and density of a part.
O’Brien and James concluded that the direct current resistivity technique appears to be capable
of not only detecting cracks but also measuring hardness and density. Eddy current testing can be used
for surface crack but it is not suited for internal cracks. Computed Tomography and real X-ray imaging
have potential for detecting defects but have high cost. They said Ultrasonic testing can be applied to
sintered parts to detect defects.
9. 9
Slotwinski and EJ Garboczi (2014) applied three different techniques to monitor the porosity in
AM built parts. They used Archimedes’ method, X-Ray computed Tomography (XRCT) and Mass/Volume
measurements to determine the porosity. An image taken by XRCT (Figure 7) shows several localized
areas of porosity as well as cracks. They compared the results of these three methods and the outcomes
were as follows:
Figure 8 compares the results for the individual cylinders as measured by Archimedes and Mass/Volume
methods. There is a good agreement between each method but there are some instances of discrepancy
perhaps due to effects of water infiltration during Archimedes measurement.
Figure 9 compares the composite disk porosity results using Archimedes, the Mass/Volume of the small
cylinders and the mass/volume of the whole disks. The measured values are very close to each other.
Figure 10 compares mass/volume, XRCT and Archimedes for 14 individual cylinders, one from each disk.
The results of these methods were very similar.
11. 11
All three methods for determining porosity were generally in agreement, but each method has
its positive and negative aspect. The ultrasonic velocity measurements reported here demonstrates
sufficient sensitivity to detect small changes (~ 0.5%) in total porosity and should be sensitive enough to
detect process change in material porosity. The samples have local variations in porosity, both in build
direction and in the plane of each build. This was concluded from the images taken by XRCT and
measurements of the individual cylinders.
Meier and Haberland (2008) performed tensile tests of stainless steel and cobalt-chromium
parts. They said material exhibit anisotropic behavior. They used
* *
eff
v
P
E
v h d
= to calculate energy
density. Where
3
[J/ mm ]
[ ]
[ / ]
d [ ]
v
eff
E energy density
P effective laser power W
v scanning speed mm s
layer thickness mm
=
=
=
=
h hatch= distance [ ]mm
They concluded that a value of energy density between 40 and 90 J/mm3
(shaded region in
Figure 11) gives nearly 100 % density with the best surface quality.
12. 12
The tensile tests performed by Meier & Haberland indicated that the selective laser melting
(SLM) fabricated specimen showed lower ductility and lower elongation when compared to the parts
manufactured by a conventional method. By comparing the vertical and horizontal build specimens with
a reference material, they concluded that horizontally built specimens have higher tensile strength and
elongation compared to the vertically built. When a thickness of 75 mµ was investigated, it was found
that the vertically built part failed dramatically. This can be seen in Figure 12 showing brittle fracture
with cracks starting at inner defects. It was reasoned that this failure was due to the induced residual
stress which caused plastic deformation. The residual stresses are present as a result of high heating up
rates and low heat conduction.
When they compared 50 mµ thick layer built in different orientations. They concluded that less
obtuse the angle between the built direction and direction of load, the lower the strength. They also
found out that the tensile strength of horizontally generated parts i.e. orientation (b) and (c) as shown in
Figure 13 is higher than the tensile strength of conventionally fabricated parts.
0.2
5
limit
mR tensile strength
technical elastic
A Elongation after fracture
ρρ
=
=
=
13. 13
Meier and Haberland (2008) concluded that tensile strength, elastic limit and elongation after
fracture depends on the direction of build. If the load applied is perpendicular to the direction of
manufacture the structural properties are lower but reduction in layer thickness enhances the
properties. As pointed out earlier the tensile strength of the horizontally fabricated parts were higher
than those of conventionally manufactured. This hinted presence of residual stress in the parts.
Ng et al (2009) achieved the minimum lack of fusion and gas porosity processing conditions by
using numerical optimization. A laser power of 640 W, speed =620 mm/min, powder feed rate= 4g/min
shielding gas = 30 1/min and overlap of 45% was optimal for achieving minimum defects.
Barua et al (2014) performed vision based test. They used Red, Blue and Green (RGB) calibrated
values and radiant surface temperature to approximate the temperature of each pixel in the image.
Heat is lost by material being deposited by the processes of convection, conduction and radiation. They
explained that a defect free deposit should show gradual decrease in temperature through which the
reference cooling curve can be obtained using standard deposition parameters. Defects such as porosity
or cracks will lead to an increase in the temperature around the defective region because of interruption
of heat flow, which leads to deviation from the reference cooling curve, thus indicating the presence of
defect.
Gu et al (2013) explained the influences of energy density on porosity and microstructures of
4PH stainless steel. They applied two sets of process parameters: (a) different energy densities were
obtained by changing the scan speed and keeping laser power constant and (b) changing laser power
and scan speed to keep the energy density constant. Nearly 100% dense parts were built using 195W
laser power, 800 mm/s. Density of 7.857 g/mm was selected as threshold value for density. By varying
the process parameters the pores were studied and are presented in Figures 16, 17 and 18. For high
laser power and scan speed (195W & 1200 mm/s) pores are small compared to pores observed in Figure
17 (95W & 389 mm/s) and Figure 18 (70W & 287 mm/s). It is also noticeable that there are less un-
melted particles for 195W and 1200mm/s compared to the other two energy densities. Using
Archimedes method and image analysis they found similar results in level of porosity. They also looked
into the microstructural features and concluded that austenitic grains showed increasing diameter when
the scan speed was decreased.
15. 15
Cerniglia et al (2015) concluded that the laser ultrasonic technique can be used to inspect flaws
in laser deposited components during manufacturing. This technique can be used to inspect the
component as soon as the layer is solidified while manufacturing with a sensitivity of flaw detection of
above 100 mµ . Defects less than 100 mµ can be detected only if they are surface breaking. Defects
deeper than 300 mµ were easily detected. Flaws deeper than 800 mµ could only be detected if high
reflected waves were produced.
Abd-Elghany and Bourell (2012) evaluated 304L stainless steel and fabricated 24 different
samples with three different layer thickness (30 mµ 50 mµ and 70 mµ ) and laser scanning speeds of 70
mm/s & 90mm/s by Selective laser melting. They said that small particles of the powder exhibit better
compaction and lower tendency for porosity, thus higher density (experimental values tabulated in
Table 1). At lower scanning speeds, density increases because this powder has more time to melt due to
increased applied energy, thus allowing atoms to diffuse and fill up the voids. When the scan speed is
decreased, the surface tension of the melt pool is reduced as well. This contributes to formation of
porosity. These conclusions are similar to Rombouts et al (2006).
16. 16
The surface roughness of the parts increased with the use of larger particles inside the thick
layer (Table 2). Abd-Elghany and Bourell (2012) examined the microstructures of the specimens using
optical microscopy, SEM and XRD analysis. It was found that a layer thickness of 50 mµ and scanning
speed of 70 mm/s allow complete melting, whereas a layer thickness of 70 mµ shows increased porosity
and cracks formation due to presence of large powder
particles.
17. 17
Figure 21 shows that low scanning speed and 30 mµ layer
fabricated parts are 80% in strength compared to base line Yield
Strength of 170 MPa and Ultimate Tensile Strength of 480 MPa. But
70 mµ samples were brittle in nature because of the presence of
porosity. Yield strength and ultimate tensile strength were
measured to be 180 and 393 MPa and surface hardness was
recorded as high as 190 HV (Vickers hardness).
Ahsan et al (2011) analyzed the trend of porosity generation in Ti-6Al-4V using SEM and Micro
Computed Tomography of Gas Atomized (GA) and Plasma Rotating Electrode Powders (PREP) using the
same parameters. They found that the gas atomized deposited sample had three times more interlayer
porosities than the PREP deposition sample. Shown in Figure 23 (a) and (b).
18. 18
Figure 24 shows the trend of porosity in laser powers of 800W and 1000W. It was concluded by
Ahsan et al that the highest porosity percentage is achieved at a mass flow rate of 0.033 gs-1
. Porosity
decreases with decreasing mass flow rate until 0.066 gs-1
and then starts increasing again. PREP powder
shows lower porosity compared to GA powder. GA powder deposited samples show higher intralayer
porosity at all mass flow rates and laser powers than the PREP powder deposition samples.
19. 19
Figure 25 and 26 conclude that the gas atomized powder has pores of larger diameter compared
to PREP powder at both the laser powers of 800W and 1000 W and at different mass flow rates. There is
less porosity with diameter less than 40 micrometers in all cases. Ahsan et al concluded that PREP
powder should be used to obtain minimum intralayer porosity. This experiment showed a reduction in
porosity level to 0.0025% using PREP powder at 1000 W, 0.066 gs-1
and 5 mms-1
.
Shunmugavel et al (2015) compared the microstructure and mechanical properties of wrought
Ti-6Al-4V cylindrical rod with selective laser melting Ti-6Al-4V cylindrical rod. They found that SLM rods
have higher yield strength and ultimate tensile strength compared to wrought sample but low ductility.
The difference in these properties were agreed to be due to the difference in the microstructures of
these two sample. SLM sample exhibited trans-granular fracture as a result of their brittle nature
whereas wrought rod showed deep dimple fracture revealing ductile behavior (Figure XX). Stress- Strain
curve of the samples is shown in Fgure XXX and the values are tabulated in table 3.
21. 21
Qianchu et al revealed that fatigue crack initiated from the LOF defects in SLM Ti-64 specimens
for both vertically and horizontally built directions. LOF defect had more detrimental influence on
fatigue life due to its morphology. It was concluded that elimination of LOF defect will increase the
fatigue life significantly.
22. 22
5. Conclusion
Porosity is one of the major defects present in AM parts. Gas porosity is a result of gas trapped in
the parts and is hard to eliminate whereas lack of fusion defects occur due to insufficient density and
are mainly responsible for fatigue crack initiation.
There are so many different process parameters such as laser power, scan speed, layer thickness
that it’s hard to control the manufacturing. If these process can be controlled with accuracy, parts with
high density but not defect free can be achieved. The main trends found are a reduction in porosity with
increased laser power. Material parameters such as metal powder type, size and shape also affect the
mechanical properties of the component. Metal powders prepared by other techniques other than gas
atomization such as plasma rotating electrode can be used to overcome small percentage of porosity.
Several NDE tools have been identified that can be used to inspect these parts its quality such as
X-ray radiography, micro computed tomography, IR tomography, Ultrasonic imaging, Eddy current,
electrical resistivity etc. But there is a need to monitor the manufacturing of these parts layer by layer
while they are being produced to eliminate defects and reduce cost. This can be done by observing the
variation in radiance temperature of the deposit and IR temperature source measurement.
More research and investigations need to be conducted in order to improve and ensure the
functional integrity of the AM components.
Acknowledgement
The author of this report would like to thank Dr. Leonard Bond for his support and guidance.
23. 23
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