为了探明双向钛合金TC17在单双面激光冲击强化下残余应力分布特征, 采用数值分析方法研究了单双面冲击下残余应力分布规律.结果表明, 单面冲击稳定后会在冲击对面产生拉应力, 在冲击表面产生压应力, 双面同时冲击时一部分残余压应力抵消了拉应力, 同时又由于应力波的叠加和削弱作用, 导致残余应力水平下降;单面激光冲击强化获得的x方向和y方向的最大残余应力分别为336.709MPa和337.011MPa, 而双面同时激光冲击强化在两个方向均为326.401MPa;单面冲击会由于拉应力的产生而不利于抑制裂纹;双面同时冲击时试件两面的残余应力分布基本一致, 双面顺序冲击时先冲击面残余应力要高于后冲击面;有限大试件需考虑冲击波的横向传播对残余应力的影响.该结果对单双面激光冲击强化的残余应力分布规律研究具有一定的指导意义.%In order to study residual stress distribution characteristics of TC17 dual phase titanium alloy by one-side and two-side laser shock peening (LSP), numerical simulation was taken to analyze the residual stress distribution rules under one-side and two-side LSP. The results show that after the stabilization of one-side impact, tensile stress is generated on the opposite surface of the impact and compressive stress is generated on the impact surface. For two-side simultaneous LSP, part of the residual compressive stress is used to offset the tensile stress, and the superposition and weakening of the stress wave leads to the reduction of the residual stress level at the same time. The maximum residual stress in the x direction and y direction obtained by one-side LSP is 336.709 MPa and 337.011 MPa, while it is 326.401 MPa for two-side simultaneous LSP in both directions. One-side LSP is unfavorable for suppressing the crack due to the caused tensile stress. The residual stress distribution on both sides of the specimen is almost the same for two-side simultaneous LSP. The residual stress of the first impact surface is higher than that of the second impact surface after two-side successive LSP. The influence of transverse propagation of shock wave on residual stress should be considered for finite specimens. The result would be a certain guidance for study on residual stress distribution rules by one-side and two-side LSP.
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