Effect of strain rate on compressive behavior of Ti-based bulk metallic glass at room temperature

Compressive deformation behavior of the Ti₄₀Zr₂₅Ni₈Cu₉Be₁₈ bulk metallic glass was investigated over a wide strain rate ranging from 10^-4 to 10³ s^-1 at room temperature. Fracture stress was found to increase and fracture strain decrease with increasing applied strain rate, which were due to the decrease of the density of shear bands. Serrated flow was observed at lower strain rate. The appearance of a large number of shear bands was probably associated with flow serration observed during compression. At high strain rates, the rate of shear band nucleation was not sufficient to accommodate the applied strain rate and thus caused an early fracture of the test sample. The positive strain rate dependence of compressive strength might be associated with the different microstructure on the atomic scale in the Ti-based amorphous matrix.