Strong composition-dependence on glass-forming ability in Ni–(Ti,Zr)–Si pseudo-ternary alloys

The glass formation in Ni–(Ti,Zr)–Si pseudo-ternary alloys was studied. For suction casting, by carefully adjusting the alloy composition and studying the microstructure changes, the best glass-forming alloy with a 2 mm diameter is pinpointed in a narrow composition region of 57.5–58.5 at.% Ni, 36.5–38.5 at.% (Ti + Zr) and 5–5.5 at.% Si. The main competing crystalline phases, identified by XRD and SEM, were Ni10(Zr,Ti)7, Ni(Ti,Zr) and an unidentified Si-containing phase. Our results indicate a clear need for monitoring the microstructure change in the cross section of the ingots to locate the best glass-forming alloys.