Influence of the Crystalline Phase on Strain-Rate Sensitivity of a Zr-Cu-Ni-Al Bulk Metallic Glass at Room Temperature

In this work, Zr₅₃Cu_18.7Ni₁₂Al_16.3 alloy has been cast into rod samples with different diameters. Glassy composites with various volume fractions of quenched-in crystalline are obtained. Their mechanical behaviors and fracture mechanisms have been investigated upon both quasistatic and dynamic loading. As the volume fraction of crystalline phase increases, the increase in the strain-rate sensitivity exponent could be attributed to the combination of the reduction of the shear band-related deformability and the enhancement of the dislocation-related deformability. These results may shed more insight on optimizing the microstructure and performance of bulk metallic glass composites in the future.