文献类型：期刊文献

英文题名：Lamellar aspect-ratio and thickness-dependent strength-ductility synergy in pure nickel during in-situ micro-tensile loading

作者：Wang, Zi-Meng[1];Jia, Yun-Fei[1];Li, Kai -Shang[1];Zhang, Yong[1];Cai, Jia-Dong[1];Zhang, Xian-Cheng[1];Hirakata, Hiroyuki[2];Tu, Shan -Tung[1]

机构：[1]East China Univ Sci & Technol, Sch Mech & Power Engn, Key Lab Pressure Syst & Safety, Minist Educ, Shanghai 200237, Peoples R China;[2]Kyoto Univ, Dept Mech Engn & Sci, Kyoto 6158540, Japan

年份：2023

卷号：157

起止页码：89

外文期刊名：JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY

收录：;EI(收录号：20231413852075);WOS:【SCI-EXPANDED(收录号:WOS:000976885400001)】；

基金：This work was supported by the National Natural Science Foundation of China (grant Nos. 52222505, 51975211, and 51725503); Shanghai Rising-Star Program (grant No. 20QA1402500); and Foundation Strengthening Plan Technology Field Fund Project (grant No. 2019-JCJQ-JJ-454).

语种：英文

外文关键词：Lamella; In -situ micro -tensile test; Strength -ductility synergy; Aspect ratio; Grain rotation

摘要：In order to overcome the trade-off between strength and ductility in traditional metallic materials, the gradient lamellar structure was fabricated through an ultrasound-aided deep rolling technique in pure Ni with high stacking fault energy after heat treatment. The gradient lamellar Ni was successively di-vided into three regions. In-situ micro-tensile tests were performed in different regions to reveal the corresponding microscopic mechanical behaviors. Microscopic characterization techniques were adopted to explore the effects of microstructural parameters and defects on mechanical properties. This work demonstrates that the micro-tensile sample with small lamellar thickness and large aspect ratio possesses excellent strength and ductility when the loading direction is parallel to the long side of lamellar grain boundaries. The finding is helpful to the design of metallic material microstructure with superior com-prehensive properties. On one hand, the reason for high strength is that the strength increases with the decrease of lamellar thickness according to the Hall-Petch effect. Besides, initial dislocation density also participates in the strengthening mechanism. On the other hand, the deformation mechanisms include dislocation slip, grain rotation, and the effects of grain boundaries on dislocations, jointly contributing to good ductility.(c) 2023 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science & Technology.