Dynamic Void Growth and Localization Behaviors of Glassy Polymer Using Nonlocal Explicit Finite Element Analysis

This work introduces the nonlocal integral theory into the finite-deformation viscoplastic Gurson-type model for glassy polymer with plastic softening under strain rate loading. In order to improve computational efficiency and numerical robustness, nonlocal averaging on the void volume fraction is coupled with the update of stress and strain using ABAQUS dynamic subtoutines. From two numerical examples using nonlocal FEA on the unnotched square plate and the dumbbell-shaped specimen under tension respectively, the introduced length scale is demonstrated to regularize the dynamic initial-value problem well that remains hyperbolic by predicting the nonlocal void growth, the objective load responses, and the contours of localization bands accurately. In addition, the relationship between the width of localization band and the length scale is also studied.