Interaction of crack with twins in hot-rolling AZ31 magnesium alloys during in-situ TEM straining experiments  

作　　者：吴落义 伍翠兰 夏伟军 陈振华 

机构地区：[1]Center of High Resolution Electron Microscopy,College of Materials Science and Engineering, Hunan University [2]College of Materials Science and Engineering,Hunan University

出　　处：《中国有色金属学会会刊：英文版》2007年第A01期457-460,共4页Transactions of Nonferrous Metals Society of China

基　　金：Project(2006FJ4238) supported by the Research Fund for the Post-Doctoral Program of Hunan Province, China

摘　　要：In-situ straining experiments in transmission electron microscopy were performed to investigate the propagation of crack,twinning and interaction of crack with twins. Lots of micro-twins were observed in the deformation band near the tip of crack. The stress is relaxed by the formation of micro-twins and the densely developed micro-twins prevent the growth of crack from the deformation band,subsequently the cracks extend into adjacent grains across grain boundaries,and grow along cleavage plane. Multiple twins are observed in hot-rolling AZ31 magnesium alloys,when cracks propagate into twins through twin grain boundaries(GBs),the direction of growth deviates. It is concluded that twins,especially multiple twins effectively baffle the development of crack.In-situ straining experiments in transmission electron microscopy were performed to investigate the propagation of crack, twinning and interaction of crack with twins. Lots of micro-twins were observed in the deformation band near the tip of crack. The stress is relaxed by the formation of micro-twins and the densely developed micro-twins prevent the growth of crack from the deformation band, subsequently the cracks extend into adjacent grains across grain boundaries, and grow along cleavage plane. Multiple twins are observed in hot-rolling AZ31 magnesium alloys, when cracks propagate into twins through twin grain boundaries（GBs）, the direction of growth deviates. It is concluded that twins, especially multiple twins effectively baffle the development of crack.

关 键 词：镁合金 物理性能 电子 转移模式 

分 类 号：TG115[金属学及工艺—物理冶金]