Effect of external disturbances on the strain-rate dependent plastic deformation behavior of a bulk metallic glass

In this work, the effect of external disturbances on the strain-rate dependent plastic deformation behavior of a Zr57Cu20Al10Ni8Ti5 bulk metallic glass (BMG) has been examined by tailoring the geometric confinement, stress gradient, and sample size. With the external disturbances, the fracture strains of the BMG specimens become less dependence on the strain rates, and it is found that the confinement of the propagation of shear bands is the dominant deformation mechanism. This is different from previous findings in that multiplication of the shear bands also plays a critical role in accommodating the plastic deformation of BMGs with external disturbances. The present findings not only shed more light on the deformation mechanisms of BMGs under external disturbances, but also suggest that the use of external disturbances can reduce the dependence of the plastic deformation behavior of BMGs on the strain rates. (C) 2016 Elsevier B.V. All rights reserved.