Investigation of viscosity and crystallization in supercooled-liquid region of Zr-based glassy alloys

Abstract Using viscosity measurement method and in-situ heating synchrotron radiation, the viscosity of the (Zr0.55Al0.1Ni0.05Cu0.3)100 − xYx (x = 0, 0.5, 1, 2) bulk metallic glasses (BMGs) in their supercooled liquid regions (SLRs) and the in-situ heating nucleation were investigated, respectively. In the SLR, the (Zr0.55Al0.1Ni0.05Cu0.3)99Y1 metallic glass which shows distinct plastic strain in compression exhibits higher viscosity than the other three BMGs, however their Poisson's ratios are almost the same. The synchrotron diffraction results show that crystallization happened in the SLR of the (Zr0.55Al0.1Ni0.05Cu0.3)99Y1 glassy alloy, which could be the reason for the higher viscosity and larger plastic strain in compression compared to the other three alloys. The fracture surfaces of the glassy alloys were observed and analyzed.