Effect of Ni on stabilization of the supercooled liquid and devitrification of Cu–Zr–Ti bulk glassy alloys

Cu57.5Zr30Ti10Ni2.5 and Cu55Zr30Ti10Ni5 bulk glassy alloys exhibit high compressive fracture strength of 2200 and 2100 MPa, respectively, and a large supercooled liquid region. Addition of Ni significantly influences devitrification of Cu–Zr–Ti glassy alloy. Cu57.5Zr30Ti10Ni2.5 glassy alloy primarily forms an intermediate intermetallic compound on heating prior to equilibrium by the diffusion-controlled growth with low energy barrier for nucleation whereas Cu55Zr30Ti10Ni5 and Cu52.5Zr30Ti10Ni7.5 glassy alloys devitrify forming equilibrium Aba2 (Cu,Ni)10(Zr,Ti)7 phase with slightly reduced lattice parameters compared to Cu10Zr7 and a small fraction of an unidentified phase. However, pre-existing nanoscale phase of less than 10 nm in size is located in the spaces between the (Cu,Ni)10(Zr,Ti)7 dendritic phase in the spaces between nanoparticles.