报告题目：Microstructure Evolution during Friction Stir Welding of Metallic Materials
报告人：Prof. Hiroyuki Kokawa，日本东北大学教授、原日本焊接学会主席、上海交通大学讲席教授
时 间：2019年5月29日上午 (周三) 9:00
地 点：仲英楼 材料学院第二会议室
Friction stir welding (FSW) is a revolutionary joining technique invented in 1991. This technique is widely considered as one of the most significant recent achievements in the field of joining. Being a solid-state process, FSW avoids solidification problems associated with conventional fusion welding and thereby yields sound joints, even in materials usually considered to be unweldable. The triumph of this technology resulted in its widespread usage for joining of various structural metallic materials. In turn, the practical success of the friction stirring techniques necessitates a more fundamental understanding of the underlying physical processes. Thus, microstructural and textural studies are presently becoming one of the key issues in the friction stirring field. The frictional heat and material flow during FSW form fine-grained microstructures with microtextures in metallic materials. Characteristics and distributions of microstructures often determine the weld properties. We have been conducted metallurgical studies of microstructures and properties of friction stir welded materials. I would like to introduce several achievements in this field by reviewing our previous studies.
Dr. Hiroyuki Kokawa (粉川博之) is a Chair Professor at Shanghai Jiao Tong University from April 2017. He obtained his B.S. in 1974 and Ph. D. in 1979 from Tohoku University, Japan (日本东北大学), both in materials science. Then he joined Welding Engineering and Technology Laboratory in Department of Materials Processing at Tohoku University, where he served as a full professor and the director of the laboratory from 1996 to 2017 for 21 years until his retirement in March 2017. He has performed considerable research regarding welding metallurgy, especially on grain boundary engineering and friction stir welding. He has authored or co-authored 207 SCI-publications (Times cited: 6906, H-index: 42 in Web of Science on April 19, 2019), and received many awards and prizes from academic societies, such as Japan Welding Society (JWS日本焊接学会), American Welding Society (AWS), Japan Welding Engineering Society (JWES日本焊接协会), Japan Institute of Metals (JIM日本金属学会), Iron and Steel Institute of Japan (ISIJ日本钢铁协会). He is a Key Reader, Metallurgical and Materials Transactions Board of Review (TMS) and an Editorial Board Member of the journal “Science and Technology of Welding and Joining”. He was the President of JWS (2014-2016), and Executive Board Member of JWES, JIM and Japan Light Metal Welding & Construction Association (JLWA).