关键词: 挖补结构, 挖补参数, 代理模型, 优化设计, 拉伸强度, 复合材料

Abstract: To obtain the optimization of scarf repair structure of CFRP laminates. Firstly, a three-dimensional damage accumulation model is established through three-dimensional solid elements, and the validity of the established simulation model is verified through experiments. Moreover, a surrogate model of tensile strength was constructed using Latin hypercube sampling (LHS) method and response surface method (RSM). Finally, the optimized design of scarf repair structure is obtained by combination of the surrogate model and genetic algorithm (GA). The research results show that, the error is less than 10% between the numerical and experimental results, indicating that the established finite element model is valid. The failure model of the scarf repair structure under tensile load is mainly the shear failure of the adhesive layer. The adhesive layer damage starts at the position corresponding to the 0° layer of the laminates and the patch, and then expands around. After the adhesive layer fails, the patch loses its load. Capacity, the mother board continues to bear the load and breaks at the narrowest point. The best adhesive layer thickness, scarf repair angle and rotation angle are 0.1035 mm, 2.5° and 0°, respectively. Compared with the conventional scarf repair structure, the tensile strength is increased by 12.57%. Genetic algorithm is used to optimize the scarf repair structure of CFRP laminates, which is of great significance to improve the mechanical properties of scarf repair structure.

Key words: scarf structure, scarf parameters, proxy model, optimized design, tensile strength, composites