Annealing effect on mechanical properties and strain localization of a Zr-based metallic glass under shear

Abstract

Fracture behavior under shear load is important for understanding the intrinsic deformation and fracture mechanism of metallic glasses (MGs). However, due to the limit forming of MGs, shear testing still remains a challenge in terms of traditional mechanical methods. In this study, the annealing effect on mechanical properties and strain localization of Zr52.5Cu17.9Ni14.6Al10Ti5 MG were investigated under shear load using a digital image correlation (DIC) method. Firstly, the shear strength, as well as fracture angle and fracture surface morphology, were systematically analyzed and compared for MGs annealed at different temperatures. Secondly, the shear strain evolution in calculated region by DIC method was obtained from full-field deformation measurements. Data analysis revealed that a higher degree heterogeneity of local strain corresponded to a lower annealing temperature, which correlated with a greater load capacity. Thirdly, a novel method was proposed for gauging shear modulus by bimodal Gaussian distribution. These findings have implication for understanding the deformation behaviors and fracture mechanisms of MGs under shear.