Deformation Morphology underneath the Vickers Indent in Bulk Metallic Glasses
XING Dong-Mei1,3, ZHANG Tai-Hua1, WEI Bing-Chen2
1State Key Laboratory of Nonlinear Mechanics (LNM), Institute of Mechanics, Chinese Academy of Sciences, Beijing 100080
2National Microgravity Laboratory, Institute of Mechanics, Chinese Academy of Sciences, Beijing 100080
3College of Physics and Electronic Information Science, Tianjin Normal University, Tianjin 300072
Deformation Morphology underneath the Vickers Indent in Bulk Metallic Glasses
XING Dong-Mei1,3;ZHANG Tai-Hua1;WEI Bing-Chen2
1State Key Laboratory of Nonlinear Mechanics (LNM), Institute of Mechanics, Chinese Academy of Sciences, Beijing 100080
2National Microgravity Laboratory, Institute of Mechanics, Chinese Academy of Sciences, Beijing 100080
3College of Physics and Electronic Information Science, Tianjin Normal University, Tianjin 300072
Abstract： Plastic deformation behaviour of Zr52.5Al10Ni10Cu15Be12.5 and Mg65Cu25Gd10 bulk metallic glasses (BMGs) is studied by using the depth-sensing nanoindentation and microindentation. The subsurface plastic deformation zone of the BMGs is investigated using the bonded interface technique. Both the BMGs exhibit the serrated flow depending on the loading rate in the loading process of indentation. Slow indentation rates promote more conspicuous serrations, and rapid indentations suppress the serrated flow. Mg-based BMG shows a much higher critical loading rate for the disappearance of the serration than that in Zr-based BMG. The significant difference in the shear band pattern in the subsurface plastic deformation zone is responsible for the different deformation behaviour between the two BMGs. Increase of the loading rate can lead to the increase of the density of shear bands. However, there is no distinct change in the character of shear bands at the loading rate of as high as 1000nm/s.
2005, Vol. 22 
