The Experts below are selected from a list of 69 Experts worldwide ranked by ideXlab platform
Alan A Luo - One of the best experts on this subject based on the ideXlab platform.
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Magnesium casting technology for structural applications
Journal of Magnesium and Alloys, 2013Co-Authors: Alan A LuoAbstract:This paper summarizes the melting and casting processes for Magnesium alloys. It also reviews the historical development of Magnesium Castings and their structural uses in the western world since 1921 when Dow began producing Magnesium pistons. Magnesium casting technology was well developed during and after World War II, both in gravity sand and permanent mold casting as well as high-pressure die casting, for aerospace, defense and automotive applications. In the last 20 years, most of the development has been focused on thin-wall die casting applications in the automotive industry, taking advantages of the excellent castability of modern Magnesium alloys. Recently, the continued expansion of Magnesium casting applications into automotive, defense, aerospace, electronics and power tools has led to the diversification of casting processes into vacuum die casting, low-pressure die casting, squeeze casting, lost foam casting, ablation casting as well as semi-solid casting. This paper will also review the historical, current and potential structural use of Magnesium with a focus on automotive applications. The technical challenges of Magnesium structural applications are also discussed. Increasing worldwide energy demand, environment protection and government regulations will stimulate more applications of lightweight Magnesium Castings in the next few decades. The development of use of Integrated Computational Materials Engineering (ICME) tools will accelerate the applications of Magnesium Castings in structural applications.
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Advanced casting technologies for lightweight automotive applications
China Foundry, 2010Co-Authors: Alan A Luo, Anil K Sachdev, Bob R. PowellAbstract:This paper provides an overview of alloy and process developments in aluminum and Magnesium Castings for lightweight automotive applications. Wear-resistant aluminum alloys, creep-resistant and high strength/ductility Magnesium alloys have been developed for automotive applications. On the process front, vacuum-assisted die casting and high vacuum die casting technologies have been developed for high-integrity body and chassis applications. Thin-wall and hollow casting components are being produced by low-pressure die casting processes for structural applications. Overcasting technology is gaining traction and has enabled mixed material designs for automotive sub-systems such as engine cradles and instrument panel beams. Simulation tools developed to predict the interfacial interactions of the dissimilar components and the structural integrity of the overcast systems are being validated in the casting trials.
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Magnesium Castings for automotive applications
JOM, 1995Co-Authors: Alan A Luo, Jean Renaud, Isao Nakatsugawa, Jacques PlourdeAbstract:The growth rate of Magnesium casting production in North America has averaged 16.6 percent per year over the last ten years.1−3 The fastest growing application for Magnesium is the high-pressure die casting for automotive components, which represents approximately 70–80% of the Magnesium casting shipments in recent years. This paper presents the latest developments in Magnesium alloys, product design, casting technology, surface finishing, and Magnesium-matrix composites. Current and future automotive applications of Magnesium Castings are also discussed.
Zhan W. Chen - One of the best experts on this subject based on the ideXlab platform.
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Incipient melting during friction stir processing of AZ91 Magnesium Castings
Materials Science and Engineering A-structural Materials Properties Microstructure and Processing, 2010Co-Authors: Joseph D. Robson, Zhan W. ChenAbstract:Abstract The microstructural evolution in as-cast AZ91 ahead of the tool has been studied during friction stir processing (FSP) using the breaking pin method. In this method, the pin is deliberately broken during FSP followed by rapid quenching of the material to freeze the microstructure. Examination of the frozen microstructure has revealed that the β-Mg17Al12 phase undergoes eutectic melting during FSP ahead of the pin and before the surrounding matrix is heavily deformed. The molten regions then collapse under the severe shear strain imposed on the matrix, and this leads to a large increase in their surface area that facilitates rapid solidification by growth of α-Mg, consuming the liquid. This mechanism leads to the small volume fraction of β observed in the final FSP material. It is promoted by the low eutectic melting temperature in the Mg–Al alloy system compared to that of pure Magnesium, and is thought more plausible than a solid state dissolution mechanism as it does not rely on an unrealistic acceleration of the solid state diffusion rate.
Joseph D. Robson - One of the best experts on this subject based on the ideXlab platform.
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Incipient melting during friction stir processing of AZ91 Magnesium Castings
Materials Science and Engineering A-structural Materials Properties Microstructure and Processing, 2010Co-Authors: Joseph D. Robson, Zhan W. ChenAbstract:Abstract The microstructural evolution in as-cast AZ91 ahead of the tool has been studied during friction stir processing (FSP) using the breaking pin method. In this method, the pin is deliberately broken during FSP followed by rapid quenching of the material to freeze the microstructure. Examination of the frozen microstructure has revealed that the β-Mg17Al12 phase undergoes eutectic melting during FSP ahead of the pin and before the surrounding matrix is heavily deformed. The molten regions then collapse under the severe shear strain imposed on the matrix, and this leads to a large increase in their surface area that facilitates rapid solidification by growth of α-Mg, consuming the liquid. This mechanism leads to the small volume fraction of β observed in the final FSP material. It is promoted by the low eutectic melting temperature in the Mg–Al alloy system compared to that of pure Magnesium, and is thought more plausible than a solid state dissolution mechanism as it does not rely on an unrealistic acceleration of the solid state diffusion rate.
S Ji - One of the best experts on this subject based on the ideXlab platform.
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low pressure lost foam process for casting Magnesium alloys
Materials Science and Technology, 2005Co-Authors: S JiAbstract:Abstract The lost foam process is capable of making Castings with extremely complicated shapes at high soundness levels and with low manufacturing costs. However, there are several challenges to produce Magnesium Castings using the conventional lost foam process because of the low heat content of Magnesium alloys. Therefore, a novel low pressure lost foam process has been developed especially for Magnesium Castings, in which the melt is filled under counter gravity conditions at low pressure. This paper introduces the low pressure lost foam process. The measurement of flow profiles in the plate shape and the L shape EPS patterns under different conditions reveals that the process can offer unique advantages for achieving laminar flow and fully controlled flow during melt filling. The dimensional accuracy with the specially designed Castings shows that CT4–8 is achievable for Magnesium Castings produced by the low pressure lost foam process, according to the dimensional tolerance grading given in ISO8062–1...
Jacques Plourde - One of the best experts on this subject based on the ideXlab platform.
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Magnesium Castings for automotive applications
JOM, 1995Co-Authors: Alan A Luo, Jean Renaud, Isao Nakatsugawa, Jacques PlourdeAbstract:The growth rate of Magnesium casting production in North America has averaged 16.6 percent per year over the last ten years.1−3 The fastest growing application for Magnesium is the high-pressure die casting for automotive components, which represents approximately 70–80% of the Magnesium casting shipments in recent years. This paper presents the latest developments in Magnesium alloys, product design, casting technology, surface finishing, and Magnesium-matrix composites. Current and future automotive applications of Magnesium Castings are also discussed.
