Analysis on shear deformation mechanism of metallic glass under confined bending test

The shear deformation mechanism of Zr-based metallic glass under multiaxial loadings was systematically analyzed. By means of a confined bending test (CBT), some regular shear bands (SBs) initiated on the tension surface of the specimen and the metallic glass showed certain plastic deformation ability due to the stable propagation of SBs. Moreover, the angles between most of the SBs and the edges of the specimen were measured to be 55° approximately. In order to reveal the shear deformation mechanism under the CBT, a nonlinear contact analytical model based on the finite element method (FEM) was proposed. Furthermore, according to the stress results obtained by simulations, a stress analysis method was employed to establish the relationship between the SB angle and the shear deformation process. Finally, compared with the experimental results above, it was concluded that the stress gradient produced by CBT was the key factor which could stimulate certain plasticity. Additionally, the initiation and propagation of the SBs were stable due to the multiaxial stress state in specimen.