激光喷丸参数对7075铝合金残余应力分布影响规律的数值分析

为了研究不同激光喷丸参数对残余应力分布的影响规律,较快获取期望的残余应力分布,通过利用有限元软件ABAQUS对激光喷丸过程进行数值模拟,完成了7075航空铝合金靶材在不同冲击波峰值压力、冲击次数、光斑大小及搭接率等工艺参数下的数值模拟。模拟结果表明:随着峰值压力的增加,材料表面残余压应力也增加,当峰值压力增大到一定值时,材料表面残余压应力达到最大;当峰值压力一定时,材料表面及内部残余压应力随光斑大小及冲击次数的增加而增加;随着光斑搭接率的增加,材料表面残余压应力增大,且随着搭接率的增加,表面残余压应力的波动逐渐减小。

Numerical analysis on influences of laser shock peening parameters on residual stress distribution for 7075 aluminum alloy

In order to explore the influences of different laser shock peening parameters on residual stress distribution and obtain the ex-pected residual stress distribution, laser shock peening was simulated by finite element software ABAQUS under different peak pressures, shock times, sizes of the beam spot and overlapping rates for aluminium 7075. The result of numerical simulation indicates that the surface residual compressive stress increases with the increase of peak pressure, and the surface residual stress attains its maximum when the peak pressure reaches a fixed value. However, the surface and inner residual stresses also increase with the increase of beam spot size and shock times under the constant peak pressure. Thus, the surface residual stress increases with the increase of overlapping rate, and its fluctuation tends to the minimum when the overlapping rate increases.