通过应变速率跳跃模式下的单轴压缩试验,研究了含有不同体积分数B2-CuZr相的CuZr基块体金属玻璃复合材料的应变速率敏感性。结果发现,随着B2-CuZ r相体积分数的增加,在3.7×10^(-5) s^(-1)至3.7×10^(-3) s^(-1)的应变速率范围中,该复合材料的应变速率敏感指数可由负值变化为正值。但是,对于B2-CuZ r相体积分数高达约80%的复合材料,其应变速率敏感指数的正值仍然是反常的低。这一现象与B2-CuZ r相自身力学行为所呈现的有限应变速率依赖性有关,是由于变形过程中B2-CuZ r相的马氏体相变效应所致。研究结果显示,CuZr基块体金属玻璃复合材料的极限应变速率敏感性受制于B2-CuZr相。
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.