ORAL

SESSION: AdvancedMaterialsMonAM-R6	Marquis International Symposium on New and Advanced Materials and Technologies for Energy, Environment and Sustainable Development(3rd Intl Symp. on New and Advanced Materials and Technologies for Energy, Environment and Sustainable Development)
Mon Oct, 23 2017	Room: Condesa IA
Session Chairs: Jan Seidel; S. Ravi P. Silva; Session Monitor: TBA

15:30: [AdvancedMaterialsMonAM07]
Effect of Deformation Twins on Recrystallization Behavior of Magnesium Alloy Sheets
Jae H. Kim¹ ; Byeong-chan Suh² ; Ji Hyun Hwang³ ; Myeong-shik Shim¹ ; Nack Kim¹ ; ¹POSTECH, Pohang, Korea (Republic of [South] Korea); ²NIMS, Tsukuba, Japan; ³Pohang University of Science and Technology, Pohang, Korea (Republic of [South] Korea);
Paper Id: 110 [Abstract]

In recent years, there has been a great interest in the weight reduction of automobiles for energy conservation and environmental protection. One of the most effective ways to reduce the weight of vehicles is the use of lightweight materials such as Mg alloys as structural components in vehicles. Mg alloys have the lowest density among commercially available structural alloys and recent studies have shown that some Mg alloys have good mechanical properties comparable to those of Al alloys. However, Mg alloys have a critical shortcoming that needs to be overcome, poor formability at room temperature mainly originated from strong basal texture developed during thermomechanical processing. Although several Mg alloys show random/weak texture and accordingly good room temperature formability, most of such alloys rely on the usage of expensive rare earth elements. In the present work, an attempt has been made to modify the texture of Mg alloys by utilizing deformation twins as nuclei for recrystallization. The main impetus for such approach comes from the idea that various deformation twins formed in Mg alloys have different orientation relationship with the matrix and accordingly can induce the formation of recrystallized grains with different orientations. The orientation relationship between parent grain, deformation twins, and recrystallized grains has been analyzed by ex-situ heating EBSD in both as-rolled and annealed conditions to understand how deformation twins affect the orientation of recrystallized grains.

SESSION: AdvancedMaterialsMonAM-R7	Marquis International Symposium on New and Advanced Materials and Technologies for Energy, Environment and Sustainable Development(3rd Intl Symp. on New and Advanced Materials and Technologies for Energy, Environment and Sustainable Development)
Mon Oct, 23 2017	Room: Condesa IB
Session Chairs: Toshinori Okura; Carlos Enrique Schvezov; Session Monitor: TBA

15:30: [AdvancedMaterialsMonAM07]
Effect of Alloying Element on Deformation Behavior of Binary Magnesium Alloys
Ji Hyun Hwang¹ ; Byeong-chan Suh² ; Jae H. Kim³ ; Myeong-shik Shim³ ; B. J. Lee¹ ; Jaimyun Jung¹ ; H. S. Kim¹ ; Nack Kim³ ; ¹Pohang University of Science and Technology, Pohang, Korea (Republic of [South] Korea); ²NIMS, Tsukuba, Japan; ³POSTECH, Pohang, Korea (Republic of [South] Korea);
Paper Id: 111 [Abstract]

As the lightest of structural alloys, Mg alloys offer significant potential for weight reduction, but have yet to see the significant application in automobiles, particularly in sheet form. One of the major drawbacks preventing such application is their poor formability at room temperature, originating from their strong basal texture and the limited number of slip systems. Therefore, numerous studies have been conducted to improve the formability of Mg alloys by alloy modification and weakening/randomizing the texture. Although the effect of alloying elements on the modification of texture is relatively well understood, the intrinsic effect of alloying elements on the deformation behavior of Mg alloys is not clearly understood yet. The present work is aimed at having a better understanding of the effect of alloying elements on the deformation behavior of Mg alloys. Among various elements utilized in Mg alloys, four representative alloying elements have been chosen; Al and Zn that are most commonly used alloying elements in Mg alloys, Sn that is known to increase ductility and promote significant precipitation hardening in Mg alloys, and Y that represents rare earth elements used in numerous Mg alloys. The binary alloys containing these elements have been cast and subjected to various thermomechanical treatment to have the similar grain size. Their deformation behavior has been analyzed by in-situ tensile test with EBSD, and the result has been compared with the VPSC simulation analysis to identify the role of each alloying element in the deformation behavior.