Strength of 2D materials with multiple defects

GQ Zhang and HS Qin and YL Liu, THIN-WALLED STRUCTURES, 217, 113897 (2025).

DOI: 10.1016/j.tws.2025.113897

The coexistence of multiple defects such as voids, cracks, and grain boundaries (GBs) significantly degrades the mechanical properties of two-dimensional (2D) materials. Understanding the effect of defect interactions on strength is crucial for effective defect engineering. In this study, we employed molecular dynamics (MD) simulations to investigate the fracture behaviors of graphene and h-BN with paired defects. Our results reveal a transition from single-defect dominated failure to coupled failure of defect interactions as the defect distance decreases. Detailed analysis shows that the intrinsic bond strength remains invariant, independent of loading states, fracture bonds, defect distances, and defect types, but solely determined by its chemical environment. In contrast, the amplification factor of the local bond stress to externally applied bond stress increases as the defect distance decreases, driving the reduction in overall strength. By integrating the intrinsic bond strength and local bond stress, we propose a unified strength criterion for 2D materials with multiple defects, which provides a deep unraveling of fracture behaviors in 2D materials with complex defect interactions.

Return to Publications page