A Novel Residual Fatigue Limit Prediction Approach for Impact‐Damaged CFRP Laminates Based on Infrared Thermography

ABSTRACT While the self‐heating effect under fatigue loading has become an established method for fatigue limit prediction in various materials, its application to impact‐damaged carbon fiber reinforced polymer (CFRP) composites remains scientifically challenging. This study presents a novel multiparameter approach for fatigue limit assessment of CFRP laminates, incorporating both pre‐ and postimpact conditions through synchronized analysis of thermal response characteristics and thermodynamic entropy production rates under progressive loading amplitudes. The research introduces the Damage Heat Generation Area (DHGA) as a critical damage quantification parameter for residual fatigue limit prediction. Experimental validation through conventional fatigue testing demonstrates remarkable prediction accuracy, with all three proposed methods maintaining errors below 13%. Notably, the entropy production rate method achieves exceptional precision with merely 5% deviation. These findings advance the field of nondestructive evaluation by providing a thermomechanics‐based framework for damage‐state assessment and a reliable methodology for residual life prediction of composite structures with impact damage.