作　　者： (张红英）; (袁海洋）;

机构地区： 湖南财经工业职业技术学院机电工程系,湖南衡阳421002 南华大学机械工程学院,湖南衡阳421001

出　　处： 《轻合金加工技术》 2017年第8期46-49,共4页

摘　　要： 采用激光冲击强化工艺处理7075高强铝合金试件,借助无损应力测试方法分析预置缺陷和后置缺陷对冲击残余应力场分布的影响。结果表明,冲击强化可在无缺陷试件表面引入"凹"字形分布的残余应力场,冲击正、背面表现形式一致但程度不同。对于含微小缺陷的试件,主要在材料突发不连续区域呈现较大的残余应力分布状态变化。预置缺陷在缺陷边缘造成残余应力松弛,且使残余拉应力层外移,而后置缺陷在缺陷边缘一定层深内可进一步强化压应力水平。 LSP was carried out on 7075 high-strength Al alloy specimens. The impact re sidual stress distributions with preset-defect or post-defect were analyzed by the nondestructive measurement method. The results show that LSP introduces different concave residual stress fields on both the impact side and the reverse side to the specimens without defects. Considerable stress distribution variation presents when burst discontinuity occurs in the ma- terial. Moreover, the preset defect results in stress relaxation and the tensile stress layers move outside around the defects, while the post defect further intensifies the compression stress in certain layers.

关 键 词： 铝合金 激光冲击强化 残余应力 缺陷 应力松弛