基于残余应力的激光冲击强化参数多目标优化

In order to obtain the optimal processing parameters combination of GH4169 superalloy during the laser shock peening(LSP) process, ABAQUS/EXPLICIT package was used to examine the effects of four key processing parameters including overlap rate, spot size, peak pressure and pulse width on the residual stress based on a plate specimen. Then, maximum residual tensile stress, average residual compressive stress on surface and the depth of residual compressive stress were taken as optimization objectives. With the help of radial basis function (RBF) surrogate model and genetic algorithm(GA) (including non-dominated sorting GA(NSGA-II), neighborhood cultivation GA(NCGA), adaptive multi-population GA(AMGA)), the multi-objective optimization of four processing parameters was carried out. Finally, the optimal processing parameters of LSP were obtained. Numerical results show that the absolute value of average residual compressive stress on surface obtained by AMGA is 22.9MPa higher than that of NSGA-II and 59.4MPa higher than that of NCGA. The maximum residual tensile stress is decreased by 6.99%, and average residual compressive stress on surface increased by 9.78%, demonstrating the effectiveness of the optimization analysis.