为了研究6061-T6 铝合金激光喷丸后表面残余压应力在循环加载过程中的释放特性，对典型单联狗骨状试样进行激光喷丸处理及保温处理，利用MTS-809 拉扭组合材料测试系统进行不同循环应力水平和循环周次的疲劳实验，并使用X-350A 型X 射线应力测定仪测量试样表面残余压应力的变化。结果表明，残余压应力的松弛主要发生在疲劳过程开始的100 次循环周期内，1000 次循环周期后残余压应力基本趋于稳定。不同应力水平下的松弛行为表明，循环应力较小时，残余压应力松弛的幅度和速率相对较小；当循环应力接近材料屈服强度时，残余压应力松弛的幅度和速率较大，循环后期残余压应力完全释放，在表面产生残余拉应力。与未经保温处理的激光喷丸试样相比，试样经过150 ℃保温处理10 min 后，表面残余压应力下降，但在循环载荷作用下应力松弛的幅度和速率都较小，残余压应力的稳定性得以提升。

In order to investigate the relaxation rule of residual stress on laser-peening surface of 6061-T6 aluminum alloy during cyclic loading, laser-peening treatment and thermal insulation of 6061-T6 aluminum alloy has been carried out and the surface residual stress under different cyclic stress levels and circle times has been determined. The results show that most of the relaxation of residual stress occurs during the first 10 to 100 cycles, and the stress intends to be steady after 1000 cycles. Larger cyclic loading can cause greater value and rate of residual stress relaxation and even lead to complete release, especially when the peak stress is close to the yield stress. In addition, surface residual stress of the laser-peening specimens treated at 150 ℃ for 10 min is reduced and the magnitude and rate of the stress relaxation are lower. The stability of residual stress during cyclic loading is improved.