Formation and properties of Cr-Si sputtered alloys

Cr-Si metastable alloys were prepared by RF sputtering in a low-pressure argon gas. The structure of sputtered alloys results in Cr (Si) solid solution, Cr+Cr₃Si, the amorphous phase with increasing Si content for Cr-Si alloys. The dissolution hardening effect of Si increases the microhardness of Cr(Si) solid solution. The microhardness of Cr-Si sputtered alloys yields the peak around 50 at% Si, and furthermore, the microhardness of Cr-Si alloy, with Si rich content of 80at% or more increases with Si content. These results suggest that the bonding character of Cr-Si amorphous alloys is different from the metallic-to-covalent bonding of Si-rich alloys. This bonding character difference for Cr-Si rich alloys is also seen in the Si content dependence of the crystallization temperatures for Cr-Si alloys.