Dependence of initial powder temperature on impact behaviour of bulk metallic glass in a kinetic spray process

摘要

In this work, the superplasticity and brittleness of CuNiTiZr bulk metallic glass (BMG) with different initial powder temperatures (below T-g, between T-g and T-x, and above T-x) are investigated. TEM analysis, together with focused ion beam prepared samples, showed that crystallization of BMG was promoted by increasing initial temperature. Interface heating and deformability upon impact enhance the deposition of BMG particles below T-x, while rebound and fracture occurred above T-x due to the formation of a thick pre-crystallized layer around the particles. Strain induced nanocrystallization of BMGs at the impact interface may improve the bonding between amorphous particles.