For the repair structures of aircraft metal components with one-sided CFRP patches, the tensile tests on repair specimens with different repair processes (wet lay-up, prepreg and pre-curing methods) and CFRP patch parameters were carried out. The ultimate load, failure mode and interface of the specimens were observed. The three-dimensional (3D) finite element (FE) model has been established. Based on 3D Hashin failure criteria, the damage initiation and evolution in CFRP were simulated. The damages of the adhesive layer and delamination of CFRP were simulated with cohesive zone model. The FE model was validated by experimental and theoretical analysis. The results show that the three repair processes have different interface morphology and failure modes. The wet lay-up method has the best repair effect, 3.3 times of the pre-curing method and 1.3 times of the prepreg method. With the increase of patch thickness, the ultimate load first increases, then decreases, and finally tends to be stable. The failure mode gradually evolves from patch delamination, mixed failure of fiber breakage and adhesive layer damage to adhesive layer shear failure. The best patch thickness is 7 layers, about 1.05mm in thickness. With the increase of patch length, the ultimate load first increases and then decreases linearly. The damage of the adhesive layer starts from the center and both ends of the joint and evolves to the middle region. The best patch length is 80 mm. The results reported herein could provide useful guidance for the application of aviation maintenance engineering.
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