Research on low-velocity impact resistance of carbon fiber composite laminates

This research conducts a comprehensive experimental and numerical analysis of carbon fiber composite laminates under low-velocity impact conditions. Split Hopkinson Pressure Bar (SHPB) was employed to conduct impact testing on laminates with two layup sequences ((Formula presented.) and (Formula presented.)) under impacts ranging from 2 to 6 J. For assessing damage in laminates, a comprehensive progressive damage model and a simplified model were developed. The primary distinction between these models lies in the fact that the former incorporates the strengthening effect of compression on the delamination behavior, while the latter does not. Both models produce a good agreement with experimental results in terms of force–time, force–displacement curves, and absorbed energies. However, notable differences were noted in the predicted internal damage; the simplified model was underpredicted in terms of damage size and distribution compared to the comprehensive progressive damage model. Highlights: Impact tests were conducted on (Formula presented.) and (Formula presented.) composites. In order to simulate damage caused by impacts in laminates, an energy-based damage model was created, and cohesive elements were utilized to model interlaminar delamination. The strengthening effect of compression was explored. Distinct damage criteria were established for two cases. Damage detection of composites by x-rays.