波纹曲面结构对冷压消减7050铝合金残余应力的影响

Influence of Corrugated Surface Structure on Residual Stress Reduction of 7050 Aluminum Alloy by Cold Pressing

通过在7050锻态铝合金试样表面引入波纹曲面结构,在冷压消减淬火残余应力的同时,降低冷压压制载荷。采用Deform有限元软件对表面带有波纹曲面的试样进行了淬火-冷压工艺模拟优化,通过单因素变量试验,探究波纹参数对冷压残余应力的影响,并通过X射线衍射法测试残余应力进行验证。结果表明:波纹曲面试样经过淬火冷压后,试样表面和心部的应力状态表现为"拉压交替",其中,波峰处表现为压应力,波谷处表现为拉应力,波纹曲面参数对冷压消减残余应力有影响显著。试验条件下,当波纹高度为试样厚度的5%、波纹周期为试样厚度的2倍时,可以获得最优的应力消减效果。

Through the introduction of corrugated surface structure on the surface of 7050 forged aluminum alloy specimen, the residual stress of quenching can be reduced by cold pressing, and the cold pressing load can be reduced at the same time.The quenching-cold pressing process of the sample with corrugated surface was simulated and optimized by using Deform finite element software. The influence of ripple parameters on the residual stress after cold pressing was investigated by single factor variable experiment. The residual stress was tested by X-ray diffraction. The results show that, after quenching and cold pressing, the stress state of the surface and core of the specimen is "alternation of tension and compression". Where,there is a compressive stress at the peak of the wave, the wave valley is characterized by tensile stress. The influence of wavy surface parameters on the residual stress reduction by cold compression is significant. Under the experimental conditions, the optimum stress reduction effect can be obtained when the ripple height is 5% of the thickness of the specimen and the period of the ripple is 2 times of the thickness of the specimen.