An energy-dissipation-based approach for fatigue performance evaluation and life prediction of CFRP laminates

In this study, a novel fatigue life prediction model for composite laminates is proposed on the basis of energy dissipation. The total energy dissipated during fatigue can be partitioned into two contributions: damage-unrelated energy dissipation and damage-related energy dissipation. On this basis, a theoretical model is developed to relate the stabilized dissipated energy to the fatigue stress amplitude. Subsequently, the dissipated energy associated with damage evolution is quantified by separating the energy dissipation mechanisms below and above the fatigue limit. Finally, a method combining the cyclic stress–strain response with critical cumulative damage energy ( Γ CDE ) is proposed to enable rapid prediction of the fatigue life of composite materials. The accuracy of the proposed energy dissipation model and fatigue life prediction model has been validated for the tested laminates over the investigated stress range. The predicted stabilized dissipated energy agrees with experimental data within ± 30%, and most fatigue life predictions fall within a factor of 2.0 of the experimental values. • An approach based on energy dissipation was developed for fatigue performance evaluation of CFRP laminates. • Stabilized dissipated energy was modeled and partitioned into damage related and damage unrelated components. • A double curve method using SDE enabled rapid identification of fatigue limits with errors below 4%. • The proposed approach predicted fatigue life effectively, with 90.7% of results falling within a factor of 2.