在双面激光同时冲击金属薄板过程中，板料厚度是影响其冲击强化效果的重要因素。利用ABAQUS软件对双面激光同时冲击不同厚度的AM50镁合金板料进行模拟，系统研究了板料厚度对双面激光同时冲击强化效果的影响机理，对比分析了不同模型沿表面径向和轴向的残余应力分布。结果表明，在激光光斑直径、脉冲宽度、峰值压力不变的情况下，随着板料厚度增大，模型内部的残余压应力分布渐趋均匀和有规律，残余压应力影响深度逐渐变深，当板料厚度达到某一阈值后，两者都达到饱和。在激光峰值压力1600 MPa、光斑半径3 mm和压力脉冲宽度57 ns工艺参数下，双面激光同时冲击AM50镁合金薄板的理想厚度为4 mm及以上。

Sheet thickness is an important factor affecting shock effect when metal sheet is treated by two-sided simultaneous laser shock processing (LSP). AM50 Mg alloy sheets with different thicknesses are treated by two-sided simultaneous LSP, residual stress fields of all AM50 Mg alloy sheets are simulated by ABAQUS software. Influence mechanism of two-sided simultaneous LSP on metal sheet as a function of sheet thickness is systematically investigated, then residual stress distributions in the axial and radial direction are analyzed. Results show that under the same laser spot diameter, pulse width and peak pressure, with sheet thickness increasing, compressive residual stress in the model becomes more uniform and regular, and the influence depth turns deeper. When the sheet thickness reaches a threshold, both of them reach saturation. The appropriate thickness of AM50 Mg alloy sheet treated by two-sided simultaneous LSP should be 4 mm and more, when peak pressure is 1600 MPa, pulse width is 57 ns and laser spot diameter is 3 mm.