Three-point bending damage detection of GFRP composites doped with graphene oxide by acoustic emission technology.

The incorporation of graphene oxide (GO) into composite materials can modulate their overall performance. To enhance the performance of acoustic emission (AE) signals, 3% GO was incorporated into glass fiber-reinforced polymer (GFRP) composites, resulting in the creation of GO-GFRP composite materials. The sentry function was first used to investigate the damage evolution of the material. Then, the AE signals were analyzed using multivariate mode decomposition (MVMD) and the generalized S transform to identify the damage mechanisms. Finally, scanning electron microscopy (SEM) was used to observe the fracture surfaces of the samples to confirm the material failure. The experiments identified four damage mechanisms: matrix cracking, fiber debonding, delamination failure, and fiber breakage. It was also found that GO-GFRP composites are more prone to fiber debonding compared to GFRP composites without added GO.