Effects of ion implantation on surface structures and properties for bulk metallic glass

A plate-like Zr55Cu30Ni5Al10 bulk metallic glass (BMG) was prepared and Co ion implantation was carried out. The effects of ion implantation on surface structures and properties of the BMG have been studied. The results showed, after Co ion implantation, the BMG specimen still maintained an amorphous structure on the whole. Ion implantation changed the thermodynamic parameters and enhanced the thermal stability of the amorphous alloy. Along the depth direction, cobalt element implanted basically existed in a metal state. The maximum enhancement of surface micro-hardness was about 103 Hv or 18%. The average friction coefficients before and after ion implantation were 0.331 and 0.168, respectively, and the corresponding grinding trace widths were 80.23 and 60.17 μm, respectively, i.e., the Co ion implantation has reduced the average friction coefficient and corresponding grinding trace width by about 52.3% and 32.68%, respectively. The reasons of efficient improving the surface performances by ion implantation surface modification in BMG were analyzed and discussed.