Acoustic Emission-based Tensile-tensile Fatigue Damage Monitoring and Quantification of Multidirectional Pre-perforated Composite Laminates

Abstract

Abstract—Glass fiber-reinforced composites (GFRP) are prone to undetectable damage, posing challenges to their safe application in aerospace, transportation, and other fields. This study integrated acoustic emission (AE), microscopic visualization, and digital image correlation (DIC) techniques to monitor and quantify damage in multidirectional pre-perforated GFRP laminates under tensile-tensile fatigue loading. It analyzed the intrinsic correlations between surface strain evolution, AE characteristic parameters (amplitude, energy, duration, etc.), and damage modes (matrix cracking, delamination, fiber breakage) of laminates with different fiber orientations, and established the AE-based damage variable D_AE. Its validity was verified using stress-strain curves and damage micromorphology. Results showed that fiber orientation significantly affected the mechanical response and damage behavior of laminates. AE parameters and surface strain effectively characterized damage mechanisms, with obvious differences in strain distribution, stress-strain curves, and AE signals among laminates with different orientations. The engineering error of D_AE for fatigue damage characterization was within 20%, confirming the feasibility of AE technology in quantifying composite fatigue damage and providing key support for composite structural damage monitoring and life prediction.