Diffusion behavior of Ni in Zr48Cu36Ag8Al8 bulk metallic glass within supercooled liquid region
(1. State Key laboratory of Solidification Processing, Northwestern Polytechnical University, Xi’an 710072, China;
2. Northwestern Institute for Nonferrous Metal Research, Xi’an 710016, China)
2. Northwestern Institute for Nonferrous Metal Research, Xi’an 710016, China)
Abstract: Diffusion behavior of Ni in Zr48Cu36Ag8Al8 metallic glass was investigated in the temperature range of 683-723 K by secondary ion mass spectrum (SIMS) and transmission electron microscope (TEM). The diffusivity of Ni in Zr48Cu36Ag8Al8 is reasonably ？tted by a single Arrhenius relation with small effective activation energy. The diffusivity of Ni in Zr48Cu36Ag8Al8 is an instantaneous function of annealing time in the supercooled liquid region. In addition, a large number of nano-crystals are detected near the interface of Ni-Zr48Cu36Ag8Al8 diffusion couple, and its width is broader than the Ni diffusion depth determined by SIMS. The results indicate that atomic inter-diffusion is an important factor to promote the formation of nano-crystals within the diffusion zone.
Key words: metallic glasses; diffusion behavior; interface; nano-crystal