Glass formation, microstructure evolution and mechanical properties of Zr41.2Ti13.8Cu12.5Ni10Be22.5 and its surrounding alloys

Abstract

Microstructure evolutions were studied as a function of withdrawal velocity and alloy composition for Zr41.2Ti13.8Cu12.5Ni10Be22.5 and its surrounding alloys. The results demonstrate that there is a Zr(Ti)2Cu(Ni)–Zr(Ti)Be2 pseudo-binary eutectic and a Zr(Ti)–Zr(Ti)2Cu(Ni)–Zr(Ti)Be2 pseudo-ternary eutectic in the Zr–Ti–Cu–Ni–Be alloy system. The best glass-forming region was identified to be in the pseudo-binary and pseudo-ternary eutectics. The bulk metallic glass composites with different primary phases can be obtained at the composition which lies in the region between the best glass former and the corresponding primary crystalline phase. This finding confirms that multi-component alloy systems can be considered as pseudo-binary or pseudo-ternary eutectics. A metallographic approach, based on phase selection of the glass over all the competing crystalline phases, can be used to identify the best glass formers and optimum composites in multi-component alloy systems.