The copper mesh provides effective lightning strike protection for composite structures, while its efficiency can be compromised in scarf-repaired composite structures. In this study, after verified by test results, a numerical analysis procedure was employed to predict the lightning ablation damage and residual bending performances of scarf-repaired composite laminates with copper mesh protection. Initially, the ablation damage and bending damage mechanisms of good repaired and poor repaired composite laminates were analyzed. Then, the impact of lightning strike attachment position and repair design parameters including overlap length and thickness of adhesive layer on the lighting protection performances was investigated. The results indicate that ablation damage of composite and adhesive materials near the repair area significantly compromises structural integrity and reduces the bending strength. The predominant bending failure mode of scarf-repaired woven composite laminates after lightning strike is fiber failure in warp direction, accompanied by small areas of matrix failure and delamination failure. The reestablishment level of the electrical path varies with overlap length and thickness of adhesive layer, subsequently affecting the ablation damage area and depth. This study can provide a reference for the design and process control of scarf-repair in copper mesh protected composite structures.
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