Achieving high uniformity of the elastic strain energy accumulation rate during the serrated plastic flows of bulk metallic glasses

摘要

The shear-band formation and propagation mechanisms of bulk metallic glasses (BMGs) have been studied extensively, however, the interpreting of the mechanisms of the serrated plastic flows is still challenging. In this work, the variation of the elastic strain energy accumulation rates of the serrations during the plastic flows of BMGs was examined using a statistical analysis. High uniformity of elastic strain energy accumulation rates was achieved in the serrated plastic flows under complex stress fields with three-parameter Weibull modulus reaching to 14.29, which is much larger than the value of 4.06 under conventional compression tests. The variations of the elastic strain energy accumulation rates are related to the formation and propagation of shear bands under varying loading conditions, and the high uniformity under complex stress fields is due to that the formation and propagation of shear bands can be confined to certain shearing path. The present findings are of significance for giving more insight into the mechanisms of the serrated plastic flows of BMGs.