Mechanisms of Damage Evolution in CFRP Laminates Under Lightning‐Induced Thermal Stress and Shockwave Overpressure: Combined and Individual Effects

ABSTRACT During a lightning strike, various mechanical loadings induced by the lightning arc act on composite materials and may contribute to their degradation and failure. In this study, a coupled electro‐thermal‐pyrolytic‐mechanical finite element model was developed to investigate the dynamic response and damage evolution of CFRP laminates under lightning strikes. The model incorporates the constitutive behaviors of both intralaminar and interlaminar regions, enabling analysis of the combined effects of thermal stress and shockwave overpressure, as well as decoupling their individual damage mechanisms. The results indicate that thermal stress drives upward deformation, leading to compressive stress around the pyrolyzed region. It also accelerates mechanical energy dissipation and promotes significant delamination. In contrast, shockwave overpressure primarily contributes to downward bending, edge stress development, and vibration characteristics, with limited influence on delamination. These findings provide a systematic effort to distinguish the respective roles of thermal and mechanical effects in lightning‐induced damage, offering new insights into multi‐field damage mechanisms for CFRP composites.