Study on implantation of Co ions in ZrCuNiAl bulk metallic glass

A bulk metallic glass Zr55Cu30Ni5Al10 with a dimension of 70×10×1 mm was prepared using copper mold suction casting. Co ion implantation was carried out in a MEVVA source system. XRD and DSC were utilized to determine the alloy's structure and thermal stability. XPS was adopted to analyze the surface composition and Co atomic concentration distribution. Micro-hardness was examined using a micro-hardness tester. The results showed, after Co ion implantation, that the alloy sample was still in an amorphous state on the whole. Ion implantation changed the thermodynamic parameters and enhanced the thermal stability of the amorphous alloy. Along the depth of the as-implanted amorphous alloy, the Co atomic concentration profile presented an M-like shape. Surface micro-hardness of the amorphous alloy was enhanced from 575.8 Hv to 662.6 Hv. In short, ion implantation can be used as an effective means of surface modification for bulk metallic glasses.