曲面冲击头随焊冲击旋转挤压法控制40Cr钢冷裂纹

Research on Preventing Weld Cold Crack of 40Cr by Impact Revolution Curved Rod

采用随焊冲击旋转挤压法控制高强钢冷裂纹。为了增强加载区域的塑性延展,进行了曲面冲击头的设计,对强拘束度条件下40Cr钢工件,利用冲击旋转挤压曲面头进行了间距分别为80mm、100mm和110mm的随焊加载。采用小孔法测量了接头处的残余应力。实验结果表明,随焊冲击旋转挤压法能够显著减小残余应力,从减小接头残余应力的角度控制了高强钢焊接冷裂纹。

Weld cold cracks of 40 Cr under the conditions of strong constraint degrees were controlled by the method of welding with impact revolution.In order to increase the plastic deformations of the action zones,the geometrical shapes of the impacting rod were designed to curved shapes.The residual stresses of the workpieces with and without the impact revolution effect were measured.The distances between the welding torch and impacting rod were as 80 mm,100mm and 110 mm respectively.The residual stresses at the joints were measured by small hole method.The experimental results show that the residual stress may be reduced by the method.The new method may prove the possibility on preventing weld cold cracks by reducing residual stresses.