期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：2008
卷号：105
期号：39
页码：14769-14772
DOI：10.1073/pnas.0806051105
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：We report experimental characterization of shear transformation zones (STZs) for plastic flow of bulk metallic glasses (BMGs) based on a newly developed cooperative shearing model [Johnson WL, Samwer K (2005) A universal criterion for plastic yielding of metallic glasses with a (T/Tg)2/3 temperature dependence. Phys Rev Lett 95: 195501]. The good agreement between experimental measurements and theoretical predictions in the STZ volumes provides compelling evidence that the plastic flow of metallic glasses occurs through cooperative shearing of unstable STZs activated by shear stresses. Moreover, the ductility of BMGs was found to intrinsically correlate with their STZ volumes. The experiments presented herein pave a way to gain a quantitative insight into the atomic-scale mechanisms of BMG mechanical behavior.
关键词：nanoindentation ; strain rate sensitivity ; shear band ; mechanical property ; cooperative shearing model
