Numerical modeling of ductile fracture for high-strength metallic materials with a reformulated bond-level Gurson-type peridynamic model

Abstract

This study presents a reformulated Gurson-type peridynamic model for the numerical simulation of ductile fracture in high-strength metallic materials. The approach is built within a non-ordinary state-based peridynamics framework and tightly couples the Gurson–Tvergaard–Needleman (GTN) model at the bond level. Specifically, the proposed model directly couples porosity-driven softening with bond degradation based on microscopic damage mechanisms. Then, void-controlled plasticity is embedded into peridynamics, and a bond-level two-way coupling between yield behavior and damage is achieved. Meanwhile, the fracture criterion based on the GTN void volume fraction is established as well, effectively connecting the evolution of microscopic damage with macroscopic fracture behavior, from cavity initiation and growth to crack initiation and propagation. The methodology is validated against several typical examples, illustrating its effectiveness and capacity for tensile, shear, compressive, and impact problems. Overall, the proposed model offers a numerically unified and stable framework for ductile fracture in high-strength metals across diverse stress states and dynamic loading scenarios.