Characterization of damage evolution during fatigue of composite structures accompanied with self-heating effect by means of acoustic emission

Due to the increasing use of composite materials for load-carrying structures that subjected to high-magnitude cyclic loading or vibrations, it is essential to investigate the accompanying phenomena occurring during structural degradation. The phenomenon, which may significantly accelerate structural degradation is the self-heating effect, causing intensive heating due to mechanical energy dissipation. In order to prevent sudden degradation of composite structures it is essential to characterize occurring damage types and their evolution during fatigue process. In this paper, the determination of fracture mechanisms during fatigue loading was performed based on acoustic emission analysis. The obtained results allow for clustering of acoustic emission data by type of occurring damage and correlate it with accompanying self-heating appeared during loading. This allows for proper understanding of physics of observed phenomena, which may help in design and operation of composite structures subjected to fatigue loading accompanied with self-heating effect.