摘要
本文综述了纳米孪晶金属材料的塑性变形机制.通过分析纳米孪晶二维结构变形时可启动的滑移位错类型,揭示纳米孪晶金属塑性变形的3种位错机制,即位错塞积并穿过孪晶界机制,Shockley不全位错诱导孪晶界迁移机制以及贯穿位错在孪晶片层内受限滑移机制.通过改变加载方向与孪晶界面的相对取向可实现这3类位错机制的可控转变.
A brief overview is provided about the plastic deformation mechanisms in nanotwinned metals. The unique two-dementional nanoscale twin lamellae lead to different dislocation slip systems activated during plastic deformation. It has been revealed that there are three distinctly different dislocation-mediated deformation mechanisms in nanotwinned metals, namely dislocation pile-up against and slip transfer across twin boundaries, Shockley partials gliding on twin boundaries leading to twin boundary migration, and threading dislocations slip confined by neighboring twin boundaries. It is further demonstrated that these three dislocation-mediated mecha- nisms are switchable upon changing in the loading direction with respect to twin boundaries.
出处
《金属学报》
SCIE
EI
CAS
CSCD
北大核心
2014年第2期129-136,共8页
Acta Metallurgica Sinica
基金
国家重点基础研究发展计划项目2012CB932202
国家自然科学基金项目51071153和51371171资助~~
关键词
纳米孪晶金属
变形机制
位错滑移
各向异性
力学性能中图法
nano-twinned metal, deformation mechanism, dislocation slip, anisotropy, mechanical property
