Evaluation for residual strength and fatigue characteristics after impact in CFRP composites

In this study, the residual strength characteristics of woven carbon–fiber-reinforced plastic (CFRP) composites were evaluated according to variations of the impact energy as well as the diameter of the impactor, by conducting tensile tests on impacted specimens. Then, a prediction model for the residual strength after impact was proposed, which the damaged area is replaced with an equivalent hole notch. Fatigue tests were also conducted for CFRP specimens after impact, and a prediction model for the fatigue life was proposed and verified with fatigue test results. The results of the prediction equation for residual strength after impact agree well with the experimental results. The results predicted by the fatigue life equation proposed using the incident impact energy are slightly above the boundary of the test results, but the results using the absorbed impact energy agree well with the fatigue test results.