演讲题目：Ultrafine Structure Formation by Severe Plastic Deformation in Light Alloys
演讲人：Koichi Tsuchiya (土谷浩一)
Structural Materials Unit, National Institute for Materials Science, Tsukuba, Japan.
Graduate School of Pure and Applied Sciences, University of Tsukuba, Tsukuba, Japan.
Severe plastic deformation has become a popular top-down approach to produce ultrafine microstructures in various metallic materials. Various methods have been developed such as equiangular channel pressing (ECAP), accumulative roll bonding (ARB), multi-directional forging (MDF) and high-pressure torsion (HPT). Among these HPT method is very unique method since a large shear strain can be applied even to brittle materials, e.g., intermetallics, amorphous, ceramics, hcp materials etc., because of quasi-hydrostatic nature of deformation. Although the HPT method can serve as a tool to explore new deformation modes or phase transformation in extreme condition, disadvantage may be the limitation in the size of the sample. Meanwhile, caliber rolling and swaging may be other possible methods to produce ultrafine microstructure in larger scale.
The present talk will introduce the effort to produce ultrafine microstructures in Ti alloys, Mg alloys using these conventional and non-conventional processes.
Dr. Koichi Tsuchiya is Managing Director of Research Center for Strategic Materials at National Institute for Materials Science (NIMS), and Professor in the Graduate School of Pure and Applied Sciences at University of Tsukuba. He obtained his Ph. D. in Materials Science and Engineering at Northwestern University in 1991. From 1991 to 1997, he was Assistant Professor at the Department of Applied Physics at Hokkaido University. From 1997 to 2006, he was a Lecturer and Associate Professor at the Department of Production Systems Engineering of Toyohashi University of Technology. His research interests are in structure-property relation in metallic structural and functional materials, such as, Ti alloys, steels, shape memory alloys, intermetallics and metallic glasses. He serves as a board member of Association of Shape Memory Alloys. He was awarded the Mishima Award from the Iron and Steel institute of Japan in 2014, and Research Progress Award from the Japan Society of Powder in 2002, and Powder Metallurgy and the Takagi Award from The Society of Non-Traditional Technology in 2002.