Residual impact strength of carbon/epoxy laminates after flexural loadings

Very few studies can be found in the literature about the impact strength of laminates containing pre-damages promoted by loads susceptible to occur in-service. Therefore, this work intends to study the impact strength of carbon/epoxy laminates containing pre-damages promoted by flexural loadings. For this purpose, laminates were submitted to bending loads about 36%, 47%, 65% and 94% of the ultimate flexural strength. To evaluate the presence of the damages, acoustic emission and C-Scan techniques were used. The magnitude of the initial damage has a significant influence on the impact parameter values and, on the other hand, the impact strength of laminates subjected to repeated low velocity impact loads is also strongly dependent on the damages promoted by the different bending loads.