Revisiting the glass-forming ability of Ti–Ni–Si ternary alloys

The compositional dependence of glass-forming ability (GFA) was investigated for the Ti–Ni–Si ternary alloys. Glassy ribbons varied with different thicknesses were fabricated via single-roller melt spinning. The optimized glass-forming composition was located at Ti57Ni35Si8, with a critical thickness of about 200 μm for complete glass formation. By characterizing the microstructure of arc-melted ingots of the Ti–Ni–Si ternary alloys, we demonstrate that the glass formation of the Ti57Ni35Si8 alloy correlates with the (L → Ti2Ni + TiNi + Ti5Si3) ternary eutectic reaction. In addition, the eutectic composition of the (L → Ti2Ni + TiNi + Ti5Si3) ternary and (L → TiNi + Ti5Si3) pseudo-binary eutectic reaction was determined to be in the vicinity of Ti63Ni31Si6 and Ti53Ni37Si10, with the invariant reaction temperature at 1243 and 1424 K, respectively.