Serrated plastic flow behavior and microstructure in a Zr-based bulk metallic glass processed by surface mechanical attrition treatment  

作　　者：Juan-juan Liu Qing Wang Kang Sun Sebastien Gravier Jean-jacque Blandin Bao-an Sun Jian Lu 

机构地区：[1]Laboratory for Microstructures,Institute of Materials,Shanghai University,Shanghai 200072,China [2]Department of Mechanical and Biomedical Engineering,City University of Hong Kong [3]Science et Ingenierie des Matériaux et des Procédés(SIMAP),University of Grenoble/CNRS,Grenoble-INP,Saint-Martin d'Heres Cedex 38402,France

出　　处：《Journal of Iron and Steel Research International》2017年第4期475-482,共8页

基　　金：the financial supports provided by National Natural Science Foundation of China(Grant Nos.51171099,50871063);the MOST 973 Program of China(Grant Nos.2015CB856800 and 2012CB932203)

摘　　要：The serrated plastic flow,microstructure and residual stress of a Zr_（55）Cu_（30）Ni_5Al_（10） bulk metallic glass（BMG）undergone surface mechanical attrition treatment（SMAT）have been investigated by a combination of compression tests with scanning electron microscopy（SEM）,high resolution transmission electron microscopy（HRTEM）and the incremental hole-drilling strain-gage method.It is found that SMAT leads to various microstructural modifications and residual stress distribution in the surface layers of the Zrbased BMG due to the mechanically-induced nanocrystallization and generation of shear bands.As a result,the BMG alloy exhibits a remarkable work-hardening like behavior and significant increase of plastic strain from less than 1%to 15%,and its plastic deformation dynamics yields a power-law distribution of shear avalanches.Based upon the analysis of the experimental results,it is indicated that this can be connected to the SMAT-induced microstructural modifications and the resulting residual compressive stress in the Zr-based BMG.The serrated plastic flow,microstructure and residual stress of a Zr_（55）Cu_（30）Ni_5Al_（10） bulk metallic glass（BMG）undergone surface mechanical attrition treatment（SMAT）have been investigated by a combination of compression tests with scanning electron microscopy（SEM）,high resolution transmission electron microscopy（HRTEM）and the incremental hole-drilling strain-gage method.It is found that SMAT leads to various microstructural modifications and residual stress distribution in the surface layers of the Zrbased BMG due to the mechanically-induced nanocrystallization and generation of shear bands.As a result,the BMG alloy exhibits a remarkable work-hardening like behavior and significant increase of plastic strain from less than 1%to 15%,and its plastic deformation dynamics yields a power-law distribution of shear avalanches.Based upon the analysis of the experimental results,it is indicated that this can be connected to the SMAT-induced microstructural modifications and the resulting residual compressive stress in the Zr-based BMG.

关 键 词：Bulk metallic glass Surface mechanical attrition treatment Serrated flow Microstructure Residual stress 

分 类 号：TG139.8[一般工业技术—材料科学与工程]