铝合金小孔件单双面激光冲击强化效果研究

摘要

为了研究单双面激光冲击对7050-T7451铝合金小孔件的影响,采用ABAQUS有限元软件分析了单双面强化的残余应力分布,并对比分析了残余应力曲线和单双面强化断口间的对应关系. 结果表明,双面强化的残余压应力比单面强化大120MPa,且正反面应力分布更合理;单面强化后疲劳源群位置距强化面达2.54mm,偏离了尺寸中心,而双面强化的疲劳源群大致位于尺寸中心;经单双面激光冲击强化后,试样的疲劳增益分别提高了53 .3%和156 .2%. 该研究对单双面激光冲击强化的参量选择具有一定的指导意义.%In order to investigate the effect of one-side and two-side laser shock processing ( LSP ) on 7050-T7451 aluminum alloy small-hole specimens , the residual compressive stress distribution was analyzed with finite element analysis software ABAQUS and the residual stress curves and fracture morphology were compared .The results show that the residual compressive stress introduced by two-side LSP is 120MPa, larger than that induced by one-side LSP and the front and reserve side stress distribution of two-side LSP is more reasonable .The distance from fatigue source group to treatment side after one-side LSP is 2.54mm and deviates from the dimension centre .Fatigue source group locates in the middle of the thickness after two-side LSP.Fatigue lives increase 53.3%and 156.2%after one-side and two-side LSP respectively.The research shows the guidance to parameter selection of one-side and two-side LSP.