Cu−Zr−Ti ternary bulk metallic glasses correlated with (L → Cu₈Zr₃ + Cu₁₀Zr₇) univariant eutectic reaction

Starting from Cu₆₀Zr₃₀Ti₁₀, the compositional dependence of bulk metallic glass (BMG) formation was revisited in the Cu−Zr−Ti ternary system. It was revealed that the optimal BMG-forming composition is located at Cu₆₀Zr₃₃Ti₇, for which a monolithic BMG rod 4 mm in diameter can be fabricated using copper mold casting. This composition is along, although slightly off, the univariant eutectic groove for the reaction (L → Cu₈Zr₃ + Cu₁₀Zr₇). With respect to the corresponding Cu−Zr binary alloys, Ti has a significant effect on further stabilizing the liquid, thus increasing the glass-forming ability. For the Cu₆₀Zr_40−yTi_y (3 ⩽ y ⩽ 10) series BMGs, the glass transition temperature T_g decreased with increasing Ti content, at a rate of about 2.8 K/at.%. Among these BMGs, significant compositional dependence of compressive plasticity is not observed, irrespective of the T_g change. Cu₆₀Zr₃₃Ti₇ glass exhibits maximum fracture strength around 2160 MPa.