抛丸对A5083铝合金焊接接头残余应力的影响

Effect of Ball Throwing on Residual Stress of Welded Joints of A5083 Aluminum Alloys

对A5083铝合金焊接接头进行抛丸处理,测试抛丸前后焊接接头的表面残余应力以及沿深度方向的残余应力。研究结果表明,经抛丸处理后,接头的应力平均值均呈下降趋势,抛丸前应力平均值绝大多数为正数,表示接头应力为拉应力状态,抛丸后接头应力为负数,表示接头应力变为压应力状态,残余应力处于压应力状态有利于抑制裂纹萌生,改善结构的疲劳性能。抛丸对铝合金焊接接头残余应力的影响在600μm左右,抛丸对焊接接头的改善应力大小为180 MPa左右。

Ball throwing treat was employed to welded joints of A5083 aluminum alloys. The residual stress of welded joints samples before and after ball throwing treat was tested. Test result showed that the mean residual stress decreased finally. The mean residual stress are almost composed of positive numbers which manifested it was in the tension condition before ball throwing. The mean residual stress are almost composed of negative numbers which manifested it was in the compression condition after ball throwing. The compression condition of residual stress of the welded joints can inhibit the propagation cracks and enhance the fatigue properties. The influenced depth of ball throwing was 600um and the influenced value was about 180 MPa.