Numerical study of the notch effect on the malleability of bulk metallic glasses based on the free-volume theory

In this paper, numerical study was systematically conducted to analyze the shear banding evolution in bulk metallic glasses (BMGs) with various notches subjected to the uniaxial compression, and the relation between the notched configurations and compressive malleability was therefore elucidated. Free volume was used to be an internal state variable to depict the shear banding nucleation, growth and coalescence in the BMGs with the aid of free volume theory, which was incorporated into ABAQUS finite element method code as a user material subroutine. The present numerical procedure was firstly verified by comparing with the existing experimental data, and then parameter analysis was performed to discuss the impacts of notch shape, notch size, notch orientation, and notch configuration on the plastic deformability of notched samples. The present modeling will shed some light on the failure mechanisms and the toughening design of notched BMG structures in the engineering applications.