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第52 卷 第4 期 Vol.52 No.4 2016 年4 月 第491-496 页 ACTA METALLURGICA SINICA Apr. 2016 pp.491-496 纳米孪晶Cu 中局部剪切应变诱导的退孪生行为* 白敬胜 卢秋虹 卢 磊 ( 中国科学院金属研究所沈阳材料科学国家(联合)实验室, 沈阳 110016) 摘 要 对择优取向纳米孪晶结构Cu 样品进行室温轧制变形. 微观结构研究发现, 当变形压下量为15%时, 样品中出现了 与轧制方向呈30º~45°方向(最大剪切应力方向)分布的退孪生带. 退孪生带中孪晶片层明显粗化, 孪晶界上出现大量Shock- ley 位错. 塑性变形过程中较小应变时, 纳米孪晶Cu 中局部退孪生机制是协调局部剪切应变的主要机制. 关键词 Cu, 纳米孪晶, 轧制形变, 退孪生, 剪切应变 中图法分类号 TG 146 文献标识码 A 文章编号 0412-1961(2016)04-0491-06 DETWINNING BEHAVIOR INDUCED BY LOCAL SHEAR STRAIN IN NANOTWINNED Cu BAI Jingsheng, LU Qiuhong, LU Lei Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, China Correspondent: LU Lei, professor, Tel: (024) E-mail: llu@imr.ac.cn Supported by National Basic Research Program of China (No.2012CB932202) and National Natu - ral Science Foundation of China (Nos.51420105001,and Manuscript received 2015-09-30, in revised form 2015-12-11 ABSTRACT Nanotwinned materials have attracted widespread attention due to their superior mechanical proper- ties, such as high strength, good ductility and work hardening. Experimental and molecular dynamics (MD) simula- tion results had indicated that there are three distinctly different dislocation-mediated deformation mechanisms in nanotwinned metals, namely dislocation pile-up against and slip transfer across twin boundaries (TBs), Shockley par- tials gliding on twin boundaries leading to twin boundary migration, and threading dislocations slip co