The Experts below are selected from a list of 24489 Experts worldwide ranked by ideXlab platform
C.g. Kang - One of the best experts on this subject based on the ideXlab platform.
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Semi-Solid Die forging of Al6061 wrought aluminium alloy with electromagnetic stirring:
Proceedings of the Institution of Mechanical Engineers Part B: Journal of Engineering Manufacture, 2008Co-Authors: T W Kim, H H Kim, J W Bae, S M Lee, C.g. KangAbstract:This study demonstrates the forming process of a semi-Solid material with a Solid fraction of about 45 per cent after the primary α-Al particle in the semi-Solid material is globularized during Solidification by electromagnetically stirring the molten metal poured out into the sleeve. By rheological forming experiments incorporating electromagnetic stirring (EMS) using Al6061 alloy, the process parameters are optimized to be of 0.3 m/s of forming velocity, 45 MPa of forming pressure, 10 s of stirring time, and 30 A of stirring current to get the best quality. The product exhibited the highest tensile strength of 312.8 MPa and elongation of 4.51 per cent at positions where the pressure was directly applied to the material and overlapping occurred.
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the effect of injection velocity on liquid segregation and mechanical properties in arm part fabricated by semi Solid Die casting process
Journal of Materials Processing Technology, 2006Co-Authors: C.g. Kang, P.k. Seo, S S KangAbstract:Abstract Semi-Solid Die casting of Al alloy is suitable for complicated large parts of near net shape without defect and excellent mechanical properties in comparison with conventional casting process. Die design for the product with high quality in semi-Solid Die casting is required to prevent micro porosity, inflow of oxidized substances, and liquid segregation. Therefore, shape and size of runner, position and size of overflow and air vent, and arrangement of heating line are very important. Micro porosity, unfilled phenomena, turbulent flow, and liquid segregation occurs during semi-Solid Die casting. To prevent these phenomena, defect analysis of product according to the change of injection velocity is carried out and optimal injection velocity for high quality product is proposed and simulated. Also, the measurement of mechanical properties according to various injection velocity and heat treatment condition is performed.
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Effects of Die shape and injection conditions proposed with numerical integration design on liquid segregation and mechanical properties in semi-Solid Die casting process
Journal of Materials Processing Technology, 2006Co-Authors: P.k. Seo, D.u. Kim, C.g. KangAbstract:Abstract To solve the problem of reducing the weight of automobiles for the improvement of fuel efficiency and the protection of the environment, aluminum alloy parts have been substituted for steel parts. However, aluminum-alloy parts have inferior mechanical properties to those of steel parts. To improve the mechanical properties of aluminum-alloy parts, the semi-Solid Die casting process is used in the manufacture of automobile components. Semi-Solid Die casting has a different Die structure from those of general Die casting and squeeze casting. Because the oxide skin is produced during the reheating process will cause defects when it fills the Die cavity, in semi-Solid Die casting the most important factors are the filling velocity, the area of the gate, and the position, size, the number of overflow. In this paper, a theoretically-proposed Die structure for semi-Solid Die casting is verified by experiments, and the mechanical properties of the resultant parts are also presented.
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Semi-Solid Die casting process with three steps Die system
Journal of Materials Processing Technology, 2004Co-Authors: P.k. Seo, K.j. Park, C.g. KangAbstract:Abstract In automobile suspension part, knuckle as functional component is very complex shape and required high strength. To manufacture the high strength component like knuckle with semi-Solid Die casting process, there are required reheating condition, casting plan, Die design, injection condition, defect analysis and measurement of mechanical properties. In this study, aluminum knuckle with semi-Solid Die casting process was developed to replace the conventional steel components. Semi-Solid Die casting was established to lead the laminar flow and pressure transfer to the end point of product and to avoid oxide skin and shrinkage porosity. Three steps Die system was made up two-step moving Die and biscuit cutting system. And that was suitable for center-positioned gate and designed to hold the similar filling length and applying pressure. Aluminum knuckle component made by three steps Die system designed by casting simulation. Also, injection condition was established to remove oxide skin and liquid segregation. After controlled above process parameters, tensile strength, yield strength, elongation and microstructure were investigated to verify the real automobile applicability.
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horizontal reheating of aluminum alloys and semi Solid casting for a near net shape compressor component
Journal of Materials Processing Technology, 2003Co-Authors: C.g. Kang, Youngho Jung, S.w. YounAbstract:Abstract A semi-Solid casting will have a higher internal integrity, mechanical properties and dimensional accuracy than a conventional castings. This process can reduce the manufacturing costs and finished weight for critical components. Semi-Solid castings are capable of greater dimensional repeatability, this affording considerable savings when extensive machining, salvage and scrap are key variables in the current automotive product. The most important factors regarding the semi-Solid Die casting process are the reheating method of the raw materials to the semi-Solid state, the specifications of the semi-Solid Die casting machine, the optimal injection conditions and Die design. Thus, in the present work, a horizontal-type induction heating system to obtain the optimal reheating conditions for the semi-Solid Die casting process was designed and manufactured. The mechanical properties of semi-Solid Die castings for varying Die temperatures, injection velocity and applied pressure were investigated, and the relationship between applied pressure and stroke to assess semi-Solid Die castability was proposed. Semi-Solid Die casting experiments to replace heavier cast iron compressor products with lightweight aluminum castings were also carried out. The possibility of their use for compressor parts was verified.
Qiang Zhu - One of the best experts on this subject based on the ideXlab platform.
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Impact of Intensification Pressure and Grain Refiner on the Hot Tearing Susceptibility of a Semi-Solid Cast Al-Zn-Mg-Cu Alloy
Solid State Phenomena, 2019Co-Authors: Hai Yue Zhao, Stephen P. Midson, Da Quan Li, Min Luo, Qiang ZhuAbstract:The commercial application of wrought aluminum alloys to semi-Solid casting would be extremely beneficial, as wrought alloys often exhibit better strength-ductility combinations than cast aluminum alloys. Semi-Solid casting typically reduces the hot tearing tendency, as it requires a globular microstructure and produces grain refinement, but hot tearing often still occurs during the semi-Solid Die casting of complex-shaped components produced from wrought alloys. This study examined the impact of intensification pressure and grain refinement on the hot tearing tendency of an Al-Zn-Mg-Cu alloy. Semi-Solid slurries were produced using the SEED (Swirled Equilibrium Enthalpy Device) process. A specially designed constrained rod mold was used to evaluate hot tearing. Results showed the tendency for hot tearing decreased with increasing of intensification pressure. Grain refinement (with 0.06Ti) was also found to be beneficial to the elimination of hot tearing.
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Effect of Primary α-Al Morphology in Slurry on Segregation during 357 Semi-Solid Die Casting
Solid State Phenomena, 2019Co-Authors: Hong Zhang, Fan Zhang, Da Quan Li, Stephen P. Midson, Min Luo, Qiang ZhuAbstract:Controlling the morphology of the microstructure of the slurry is important during semi-Solid Die casting. For this project, semi-Solid slugs were produced using the SEED (Swirled Enthalpy Equilibrium Device) process, where a fully liquid metal is poured into a steel crucible and cooled into the semi-Solid temperature range, and the crucible and slurry are then swirled and cooled to the appropriate temperature (and Solid fraction) for semi-Solid casting. The pouring temperature of the melt into the crucible during SEED processing has been shown to influence the morphology and size of the aluminum Solid particles within the slurry, which can influence the distribution and segregation of the Solid particles during Die casting. In this study, a specially-designed Die with a serpentine-shaped flow channel has been used to study the distribution of the Solid particles during semi-Solid Die casting. The experimental results show that a dendritic structure is formed when the liquid is poured from a high temperature, while a globular semi-Solid morphology is more easily formed when poured from a low superheat. The current results also show that a dendritic structure leads to severe segregation during Die casting.
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Influence of Rare Earth Additions on the Microstructure and Mechanical Properties of Al7Si0.3Mg Alloys Processed by Semi-Solid Die Casting and Gravity Die Casting
Solid State Phenomena, 2019Co-Authors: Da Quan Li, Qiang Zhu, Min Luo, Yong Zhong Zhang, Yong Lin Kang, Stephen P. MidsonAbstract:Microstructures with fine globular grains and refined eutectic structures are important to enhance the mechanical properties of A356 alloys processed by semi-Solid and gravity Die casting. Rare earth (RE) additions have been shown to be capable of refining both the α-Al particles as well as modify the eutectic phase of alloys. In semi-Solid Die casting, Al7Si0.3Mg alloys with RE concentrations (0, 0.1 and 0.4 wt.%) were used to prepare semi-Solid slurries using the SEED (Swirling Enthalpy Equilibrium Device) method, and subsequently semi-Solid Die cast. The same compositions of alloys were also applied to gravity Die casting. The microstructure and mechanical properties of castings in two processes have been characterized. Compared to the grains produced in gravity Die casting, globular grains with small size (260 μm) in the semi-Solid Die casting significantly enhance the UTS and elongation of alloys. Although the size of grains had no change with increasing RE concentrations in alloys. The Al-Si eutectics were changed to refined morphology with the 0.1 wt.% RE addition, which enhanced the ductility of alloys in two processes. When increasing the RE addition to 0.4 wt.%, the RE-rich phases precipitated at grain boundaries, which decreased the UTS and elongation of alloys.
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Forming conditions of blisters during solution heat treatment of Al–Si alloy semi-Solid Die castings
Rare Metals, 2018Co-Authors: Lu Hongxing, Qiang Zhu, Stephen P. Midson, Fan ZhangAbstract:In the present study, numerical simulation method was used to analyze the conditions, resulting in the formation of blisters during solution heat treatment. Blister formation is considered to occur as the height of blister reaches 5 μm. The effects of process parameters on the magnitude of the forming temperatures of blister (Tb) were discussed. Two kinds of Al–Si alloys were used to analyze the effect of mechanical properties of the alloys on blister forming conditions. Simulation results show that decreasing the initial pressure in gas hole, the long-short axial ratio of gas hole and the size of gas hole, as well as increasing the depth of gas hole and the strength of alloy are helpful to increase the critical temperature of forming blister. These conclusions are helpful for casters to understand the conditions controlling blister formation during solution heat treatment and take actions to avoid the blister defects.
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Floating Behavior of Entrapped Gas in Semi-Solid Metal
Materials Science Forum, 2017Co-Authors: Qiang Zhu, Da Quan Li, Fan ZhangAbstract:Semi-Solid Die casting technology has great advantages at defects control and has been successfully used to produce high quality aluminum alloy components for several years. In this process, semi-Solid metal with high apparent viscosity and low plunger velocity are used to avoid surface turbulence which is the main source of entrapped gas in conventional Die casting processes. But, entrapped gas still has other sources, such as melting, pouring, surface flooding and confluence weld. Solution heat treatment is always used to strengthen semi-Solid Die castings. The entrapped gas leads to blister defects, which directly decreases the acceptance rate of semi-Solid Die castings. So, the entrapped gas is still a serious issue in semi-Solid Die casting process. We stuDied the floating behavior of entrapped gas bubble in semi-Solid metal. Two floating models were established for gas bubbles with different sizes. These models were used to analyze the possibility of entrapped gas escaping from semi-Solid metal in casting practice. The results showed that entrapped gas from feed billet could not escape from the semi-Solid metal in the casting process of impeller, which was proved by experiment results. These results emphasized the importance of clean melt and semi-Solid metal. Some advices were given at last for avoiding or removing the entrapped gas in semi-Solid Die casting process.
Fan Zhang - One of the best experts on this subject based on the ideXlab platform.
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Multiphase modelling of the transient flow for Sn-15Pb and 357.0 alloys in semi-Solid Die casting process
Journal of Materials Processing Technology, 2020Co-Authors: Fan Zhang, Min Luo, Yong Zhong ZhangAbstract:Abstract The transient flow behavior of the semi-Solid slurries for Sn-15Pb and 357.0 alloys during Die casting process is investigated by experimental and numerical methods. A model for the transient-state three-dimensional multiphase flow based on the kinetic theory of granular flow is developed. This model is applied to investigate the distribution of Solid concentration, flow state, pressure variation of the semi-Solid slurry in the Die casting process. The three important aspects of the multiphase flow, flow regime, particle-particle interaction and particle-liquid interaction, are interpreted according to the characteristic of the system. The model is verified by partial filling and in-situ observation experiments. Then it is applied for the phase segregation study of an elbow cavity encountered in practice. Results indicate that the 3D multiphase model can depict the flow characteristics of the semi-Solid slurry very well. The inner arc side of the elbow cavity is easier to have liquid phase segregation than the outer arc side for the lower velocity graDients of the Solid and liquid phases.
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Effect of Primary α-Al Morphology in Slurry on Segregation during 357 Semi-Solid Die Casting
Solid State Phenomena, 2019Co-Authors: Hong Zhang, Fan Zhang, Da Quan Li, Stephen P. Midson, Min Luo, Qiang ZhuAbstract:Controlling the morphology of the microstructure of the slurry is important during semi-Solid Die casting. For this project, semi-Solid slugs were produced using the SEED (Swirled Enthalpy Equilibrium Device) process, where a fully liquid metal is poured into a steel crucible and cooled into the semi-Solid temperature range, and the crucible and slurry are then swirled and cooled to the appropriate temperature (and Solid fraction) for semi-Solid casting. The pouring temperature of the melt into the crucible during SEED processing has been shown to influence the morphology and size of the aluminum Solid particles within the slurry, which can influence the distribution and segregation of the Solid particles during Die casting. In this study, a specially-designed Die with a serpentine-shaped flow channel has been used to study the distribution of the Solid particles during semi-Solid Die casting. The experimental results show that a dendritic structure is formed when the liquid is poured from a high temperature, while a globular semi-Solid morphology is more easily formed when poured from a low superheat. The current results also show that a dendritic structure leads to severe segregation during Die casting.
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Forming conditions of blisters during solution heat treatment of Al–Si alloy semi-Solid Die castings
Rare Metals, 2018Co-Authors: Lu Hongxing, Qiang Zhu, Stephen P. Midson, Fan ZhangAbstract:In the present study, numerical simulation method was used to analyze the conditions, resulting in the formation of blisters during solution heat treatment. Blister formation is considered to occur as the height of blister reaches 5 μm. The effects of process parameters on the magnitude of the forming temperatures of blister (Tb) were discussed. Two kinds of Al–Si alloys were used to analyze the effect of mechanical properties of the alloys on blister forming conditions. Simulation results show that decreasing the initial pressure in gas hole, the long-short axial ratio of gas hole and the size of gas hole, as well as increasing the depth of gas hole and the strength of alloy are helpful to increase the critical temperature of forming blister. These conclusions are helpful for casters to understand the conditions controlling blister formation during solution heat treatment and take actions to avoid the blister defects.
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Floating Behavior of Entrapped Gas in Semi-Solid Metal
Materials Science Forum, 2017Co-Authors: Qiang Zhu, Da Quan Li, Fan ZhangAbstract:Semi-Solid Die casting technology has great advantages at defects control and has been successfully used to produce high quality aluminum alloy components for several years. In this process, semi-Solid metal with high apparent viscosity and low plunger velocity are used to avoid surface turbulence which is the main source of entrapped gas in conventional Die casting processes. But, entrapped gas still has other sources, such as melting, pouring, surface flooding and confluence weld. Solution heat treatment is always used to strengthen semi-Solid Die castings. The entrapped gas leads to blister defects, which directly decreases the acceptance rate of semi-Solid Die castings. So, the entrapped gas is still a serious issue in semi-Solid Die casting process. We stuDied the floating behavior of entrapped gas bubble in semi-Solid metal. Two floating models were established for gas bubbles with different sizes. These models were used to analyze the possibility of entrapped gas escaping from semi-Solid metal in casting practice. The results showed that entrapped gas from feed billet could not escape from the semi-Solid metal in the casting process of impeller, which was proved by experiment results. These results emphasized the importance of clean melt and semi-Solid metal. Some advices were given at last for avoiding or removing the entrapped gas in semi-Solid Die casting process.
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Development of Semi-Solid Die Casting Process Technology for Aluminium Alloy Clamp
Materials Science Forum, 2016Co-Authors: Chen Song, Qiang Zhu, Fan Zhang, Da Quan Li, Hai Xia CuiAbstract:Compared with traditional liquid and Solid processing methods, semi-Solid Die casting process can apparently overcome shrinkage cavity and porosity defects in castings and high deformation resistance and high residual stress shortcomings in forging parts. Semi-Solid Die casting process with advantages such as high efficiency and low cost, will become the optimal process for high quality automobile parts. In this study, using the clamp as an example, the author introduced product structure optimization and Die design for semi-Solid Die-casting process of aluminum alloy in a new product development.The Computer Aided Engineering technology was applied to the product structure optimization according to the stress analysis. The optimal mold structure, including cavity layout, gating system, overflow and vent systems, were confirmed based on the Die design criteria for traditional Die casting, combining with the characteristics of semi-Solid forming and the simulation results. The semi-Solid aluminum alloy clamp parts with excellent performances were finally developed successfully by means of product structure optimization, Die design, parameters optimization of Die casting process, and the mechanical properties test of products.The existing parts were optimized to make them more suitable for semi-Solid Die casting processing. In addition, a reasonable Die design specially for semi Solid processing was an important guarantee for a successful semi Solid product applied in industry. Computer numerical simulation was applied in product structure design for semi-Solid Die casting, Die design, Die-casting process optimization and other aspects, to shorten the development cycle of new product, reduce cost and improve efficiency.
P.k. Seo - One of the best experts on this subject based on the ideXlab platform.
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Numerical integration design process to development of suspension parts by semi-Solid Die casting process
Journal of Materials Processing Technology, 2007Co-Authors: P.k. Seo, H.c. Kim, Chung-gil KangAbstract:Abstract In recent years in the automobile industry, it has been necessary to reduce the weight of automobile parts. To solve this problem, lower arm parts have been fabricated with the aluminum alloy metal by semi-Solid Die casting as substitutes for steel arm parts. Aluminum alloy parts can reduce the weight of automobiles, but the mechanical properties of aluminum alloy parts are inferior to those of steel parts. In order to substitute aluminum alloys parts for steel arm parts, simulations of strength and fatigue have to be performed, before changing to new model designs. The Die design for the semi-Solid Die casting of the arm part has to be considered according to defects from air porosities, impurities and filling errors. In this study, the filling and Solidification processes were simulated in order to propose the optimal Die design.
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the effect of injection velocity on liquid segregation and mechanical properties in arm part fabricated by semi Solid Die casting process
Journal of Materials Processing Technology, 2006Co-Authors: C.g. Kang, P.k. Seo, S S KangAbstract:Abstract Semi-Solid Die casting of Al alloy is suitable for complicated large parts of near net shape without defect and excellent mechanical properties in comparison with conventional casting process. Die design for the product with high quality in semi-Solid Die casting is required to prevent micro porosity, inflow of oxidized substances, and liquid segregation. Therefore, shape and size of runner, position and size of overflow and air vent, and arrangement of heating line are very important. Micro porosity, unfilled phenomena, turbulent flow, and liquid segregation occurs during semi-Solid Die casting. To prevent these phenomena, defect analysis of product according to the change of injection velocity is carried out and optimal injection velocity for high quality product is proposed and simulated. Also, the measurement of mechanical properties according to various injection velocity and heat treatment condition is performed.
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Effects of Die shape and injection conditions proposed with numerical integration design on liquid segregation and mechanical properties in semi-Solid Die casting process
Journal of Materials Processing Technology, 2006Co-Authors: P.k. Seo, D.u. Kim, C.g. KangAbstract:Abstract To solve the problem of reducing the weight of automobiles for the improvement of fuel efficiency and the protection of the environment, aluminum alloy parts have been substituted for steel parts. However, aluminum-alloy parts have inferior mechanical properties to those of steel parts. To improve the mechanical properties of aluminum-alloy parts, the semi-Solid Die casting process is used in the manufacture of automobile components. Semi-Solid Die casting has a different Die structure from those of general Die casting and squeeze casting. Because the oxide skin is produced during the reheating process will cause defects when it fills the Die cavity, in semi-Solid Die casting the most important factors are the filling velocity, the area of the gate, and the position, size, the number of overflow. In this paper, a theoretically-proposed Die structure for semi-Solid Die casting is verified by experiments, and the mechanical properties of the resultant parts are also presented.
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Determination of Die Design Rules for Semi-Solid Die Casting Process and Its Experimental Investigation
Materials Science Forum, 2005Co-Authors: Chung-gil Kang, P.k. Seo, Byung-min KimAbstract:Die design rule for semi-Solid Die casting (SSDC) with A356 electromagnetic stirring (EMS) aluminum alloy, was proposed. The Die design rule included inspection of machine, part requirements, parting line determination, sleeve, plunger, gating system, overflow, air vent, ejector pin, and heating line design. The specification of gating system, overflow, air vent, plunger tip, and sleeve suitable for respective part were regulated. Two steps Die system of lower-positioned gate and three steps Die system of center-positioned gate were manufactured for 4 automobile suspension parts, based on the Die design rule. For the sound filling pattern and Solidification behavior, injection speeds of 4 parts were summarized to the interval (from V1 to V4). As a result of observing the microstructure of 4 parts after T6 heat treatment, primary Al-α phase was globularized and fine Si particles were distributed around the grain boundary. The mechanical properties of 4 parts with T6 heat treatment were investigated and showed ultimate tensile strength (UTS) of 330 MPa, yield strength (YS) of 250 MPa, and elongation of 7.5% as average.
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Development of Horizontal Reheating System for Semi-Solid Die Casting and Its Microstructure Evaluation
Materials Science Forum, 2005Co-Authors: P.k. Seo, Byung-min Kim, Chung-gil KangAbstract:The parts manufactured by Die casting process usually contain liquid segregation and porosities. To solve these problems, the semi-Solid forming process has been applied. The process enables material in the semi-Solid state to be completely filled, and parts with the complicated shape to be fabricated by applying relatively low pressure. This process is necessary in order to control the microstructure of the billet as well as to achieve the desired semi-Solid billet state. In this study, a horizontal high-frequency induction heating device which can be fabricated by semi-Solid forming irrespective of a billet's size was developed. A globular structure of the reheated billet and a billet's temperature distribution during the reheating process for A356 were investigated.
Chung-gil Kang - One of the best experts on this subject based on the ideXlab platform.
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A study of Die design of semi-Solid Die casting according to gate shape and Solid fraction
Journal of Materials Processing Technology, 2008Co-Authors: Chung-gil Kang, Su-hoon Lee, Byung-min KimAbstract:In this paper, the effects of gate shape and Solid fraction on filling behavior during semi-Solid processing of A356 alloys have been demonstrated by experimental and computer simulation. Effects of Solid fractions and gate shapes on material properties have been investigated through experiment and computer simulation. Although the cross-section areas of the gates were identical, the filling behavior of the semi-Solid material differed due to differences between the widths and heights of the gates. Furthermore, when the cross-section area of the gate is held constant, the increase in height plays a key role in improving mechanical properties. Because the pressure applied by the plunger transfers easily to the material during injection when the cross-section area of the cavity is large, the mechanical properties improved. Therefore, the optimization of Die design and the experimental conditions that enhance material properties are proposed in this paper.
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Numerical integration design process to development of suspension parts by semi-Solid Die casting process
Journal of Materials Processing Technology, 2007Co-Authors: P.k. Seo, H.c. Kim, Chung-gil KangAbstract:Abstract In recent years in the automobile industry, it has been necessary to reduce the weight of automobile parts. To solve this problem, lower arm parts have been fabricated with the aluminum alloy metal by semi-Solid Die casting as substitutes for steel arm parts. Aluminum alloy parts can reduce the weight of automobiles, but the mechanical properties of aluminum alloy parts are inferior to those of steel parts. In order to substitute aluminum alloys parts for steel arm parts, simulations of strength and fatigue have to be performed, before changing to new model designs. The Die design for the semi-Solid Die casting of the arm part has to be considered according to defects from air porosities, impurities and filling errors. In this study, the filling and Solidification processes were simulated in order to propose the optimal Die design.
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Determination of Die Design Rules for Semi-Solid Die Casting Process and Its Experimental Investigation
Materials Science Forum, 2005Co-Authors: Chung-gil Kang, P.k. Seo, Byung-min KimAbstract:Die design rule for semi-Solid Die casting (SSDC) with A356 electromagnetic stirring (EMS) aluminum alloy, was proposed. The Die design rule included inspection of machine, part requirements, parting line determination, sleeve, plunger, gating system, overflow, air vent, ejector pin, and heating line design. The specification of gating system, overflow, air vent, plunger tip, and sleeve suitable for respective part were regulated. Two steps Die system of lower-positioned gate and three steps Die system of center-positioned gate were manufactured for 4 automobile suspension parts, based on the Die design rule. For the sound filling pattern and Solidification behavior, injection speeds of 4 parts were summarized to the interval (from V1 to V4). As a result of observing the microstructure of 4 parts after T6 heat treatment, primary Al-α phase was globularized and fine Si particles were distributed around the grain boundary. The mechanical properties of 4 parts with T6 heat treatment were investigated and showed ultimate tensile strength (UTS) of 330 MPa, yield strength (YS) of 250 MPa, and elongation of 7.5% as average.
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Development of Horizontal Reheating System for Semi-Solid Die Casting and Its Microstructure Evaluation
Materials Science Forum, 2005Co-Authors: P.k. Seo, Byung-min Kim, Chung-gil KangAbstract:The parts manufactured by Die casting process usually contain liquid segregation and porosities. To solve these problems, the semi-Solid forming process has been applied. The process enables material in the semi-Solid state to be completely filled, and parts with the complicated shape to be fabricated by applying relatively low pressure. This process is necessary in order to control the microstructure of the billet as well as to achieve the desired semi-Solid billet state. In this study, a horizontal high-frequency induction heating device which can be fabricated by semi-Solid forming irrespective of a billet's size was developed. A globular structure of the reheated billet and a billet's temperature distribution during the reheating process for A356 were investigated.