A Concordant Shift Model for Flow in Bulk Metallic Glasses  

作　　者：Gang Wang Zbigniew H.Stachurski 

机构地区：[1]Laboratory for Microstructures, Shanghai University [2]Research School of Engineering, The Australian National University

出　　处：《Acta Metallurgica Sinica(English Letters)》2016年第2期134-139,共6页金属学报（英文版）

基　　金：supported by the grants from the Ministry of Science and Technology of China(No.2015CB856800);the National Natural Science Foundation of China(Nos.51171098 and 51222102)

摘　　要：The homogeneous plastic flow in bulk metallic glasses （BMGs） must be elucidated by an appropriate atomistic mechanism. It is proposed that a so-called concordant shifting model, based on rearrangements of five-atom subclusters, can describe the plastic strain behaviour of BMGs in a temperature range from room temperature to the supercooled liquid region. To confirm the effectiveness of the atomic concordant shifting model, a comparative investigation between the vacancy/atom model and the concordant shifting model is carried out based on the estimation of the strain rate deduced from two models. Our findings suggest that the atomic concordant shifting model rather than the vacancy/atom exchange model can well predict the large strain rate in the superplasticity of BMGs.The homogeneous plastic flow in bulk metallic glasses （BMGs） must be elucidated by an appropriate atomistic mechanism. It is proposed that a so-called concordant shifting model, based on rearrangements of five-atom subclusters, can describe the plastic strain behaviour of BMGs in a temperature range from room temperature to the supercooled liquid region. To confirm the effectiveness of the atomic concordant shifting model, a comparative investigation between the vacancy/atom model and the concordant shifting model is carried out based on the estimation of the strain rate deduced from two models. Our findings suggest that the atomic concordant shifting model rather than the vacancy/atom exchange model can well predict the large strain rate in the superplasticity of BMGs.

关 键 词：Bulk metallic glasses SUPERPLASTICITY Vacancy/atom exchange model Atomic concordantshifting model Strain rate 

分 类 号：TG139.8[一般工业技术—材料科学与工程] U213.42[金属学及工艺—合金]