Acoustic Emission Monitoring of Degradation in Plain Weave CFRP Composite Laminate

The failure process on the plain weave CFRP composite laminate under three-point bending test was monitored by acoustic emission (AE). Failure process was divided into stage I, II, and III based on the energy distribution along with the mechanical results. Moreover, various failure modes in every stage were identified by RAAF method. Damage evolution for each failure mode was further quantified and evaluated through b-value method. Results reveal that no damage can be observed in stage I, and the dominant failure mode in stage II is matrix cracking, while stage III, where the specimen actually fractured, failure modes such as matrix cracking, fibre breakage and delamination arise sequentially. It is shown that AE monitoring can be applied for characterizing and evaluate damage in plain weave composite laminate.