Strain Rate Sensitivity Variation in CuZr-based Bulk Metallic Glass Composites Containing B2-CuZr Phase

The strain rate sensitivity (SRS) of CuZr-based bulk metallic glass composites (BMGCs) containing a B2-CuZr phase with different volume fractions was investigated by performing uniaxial compression tests in a strain-rate-jump mode. It is found that the SRS exponents of the BMGCs can vary from negative to positive in the strain-rate range from 3.7×10−5 s−1 to 3.7×10−3 s−1 with increasing of the B2-CuZr phase volume fraction. However, the positive SRS exponent of the BMGC with a higher B2-CuZr phase volume fraction up to about 80% is still unexpectedly low. This is attributed to the limited strain-rate-dependence of mechanical behavior of the B2-CuZr phase, which is induced by the martensitic transformation effect of the phase during deformation. It is obvious that the SRS ceiling of the CuZr-based BMGCs is controlled by the B2-CuZr phase.