Nanoindentation response of laser shock peened Ti-based bulk metallic glass

The effect of laser shock peening (LSP) on mechanical properties of Ti-based bulk metallic glass (BMG) was investigated under nanoindentation. Two regions were generated within the specimen after the LSP: (I) the extremely thick softened region (∼300 µm) in which amounts of shear bands and excess free volume were generated; (II) the middle region where the free volume increased but nearly no shear bands were induced. The hardness decreased with the increase of the indenter depth (h), exhibiting indentation size effect (ISE). The ISE increased with the increase of the measured distance away from the laser shocked tip, indicating that the ISE was inhibited by the shear bands and excess free volume was generated by the LSP