Experimental and numerical study on residual strength of aircraft carbon/epoxy composite after lightning strike

Mechanical properties of aircraft composite laminate after lightning strike are predicted and verified based on the combination of experiment and numerical simulation. Axial compression experiment of composite laminate containing lightning strike damage is carried out and failure modes of experimental samples under three kinds of electrical current waveforms are evaluated. The main failure modes include fiber fracture, matrix cracking and delamination. The final failure load decreases with the increase of actual integral action of lightning strike. Compression failure process of composite laminate is simulated using progressive damage analysis methods such as Hashin criterion, Maximum stress criterion and TSERPES criterion, respectively. Numerical simulation and experiment results are compared and coincided well. Percentage error of Hashin criterion is the minimum compared with those of TSERPES criterion and Maximum stress criterion. Stress concentration mainly appears in both angle sides on the fixed end and lightning damage regions of composite laminate.