2A12铝合金方形光斑激光冲击强化残余应力场研究  

Investigation on residual stress field of 2A12 Aluminum alloy under square spot laser shock peening

作　　者：巩志鑫 张朕 贾梦瑜 李梦浩 刘福寒 GONG Zhixin;ZHANG Zhen;JIA Mengyu;LI Menghao;LIU Fuhan(School of Electronics and Information Engineering,Hebei University of Technology,Tianjin 300401,China)

机构地区：[1]河北工业大学电子信息工程学院,天津300401

出　　处：《河北工业大学学报》2024年第5期59-67,共9页Journal of Hebei University of Technology

基　　金：河北省自然科学基金资助项目(F2022202035)。

摘　　要：为了分析以2A12铝合金为代表的航天铝合金在激光冲击强化后表面和内部残余应力的分布,采用数值模拟的方法对2A12铝合金进行了方光斑激光冲击强化后的残余应力场计算,得到了不同激光参数下的残余应力场分布曲线。研究发现,在脉冲宽度为10 ns、光斑尺寸为4 mm的固定参数下,单光斑激光冲击强化在峰值压力为1800 MPa时残余应力分布最优,最大残余应力值为-242.1 MPa。冲击强化两次获得了最佳残余应力分布,其残余应力最大值为-403.8 MPa。此外,在多光斑激光冲击强化中,利用60%的光斑重叠率可以在表面和深度方向上产生最佳的残余应力分布。本模型模拟结果与已有实验数据吻合较好,可为实际方形光斑激光冲击强化铝合金实验提供理论指导。In order to analyze the distribution of residual stresses on the surface and in the interior of aerospace aluminum alloys represented by 2A12 aluminum alloy after laser shock peening,the residual stress field of 2A12 aluminum alloy after laser shock peening with a square spot was analyzed by numerical simulation,and the distribution curves of the residual stress field were obtained under different laser parameters.It is found that,under the fixed parameters of pulse width of 10 ns and spot size of 4 mm,the single-spot laser shock peening has the optimal residual stress distribution at a peak pressure of 1800 MPa,with a maximum residual stress value of-242.1 MPa,and the optimal residual stress distribution is obtained by shock peening twice,with a maximum residual stress value of-403.8 MPa.In addition,in multispot laser shock peening,utilizing 60% of spot overlap ratio can produce the best residual stress distribution in both surface and depth directions.The simulation results of this model are in good agreement with the experimental data,which can provide theoretical guidance for the actual square spot laser impact strengthening experiments on aluminum alloys.

关 键 词：方形光斑 激光冲击强化 2A12铝合金 数值模拟 残余应力场 

分 类 号：TG146.21[一般工业技术—材料科学与工程] TG665[金属学及工艺—金属材料]