焊接结构床身的应力与变形的测试研究

TESTING RESEARCH OF STRESS AND DEFORMATION OF WELDED STRUCTURE BODY

采用盲孔法和数字水平仪分别测试了焊接床身的焊后初始残余应力和变形,以及振动时效、热时效、抛丸处理后的应力和加工后的变形。结果表明:焊接床身的初始残余应力可高达300.6 MPa,导轨变形量最大为2882.07μm,有明显的变形;采用复合时效处理后的两件焊接床身的最大拉应力分别降低至43.8 MPa和12.1 MPa,均低于50 MPa;加工后导轨的最大直线度降低至26.7μm和23.6μm,明显减小。

The initial residual stress and deformation of welded body was measured respectively with blind-hole method and digital level.The test of residual stress after vibration aging,thermal aging and shot peening and the test of deformation after processing were done.The results show that the initial residual stress of welded body can reach up to 300.6 MPa.The maximum deformation of the guide rails is 2882.07μm,which means obvious deformation.After complex aging process,the maximum residual stress of two welded bodys respectively is reduced to 43.8 MPa and 12.1 MPa,which both below 50 MPa.After processing,the maximum straightness of the guide rail respectively is 26.7μm and 25.4μm,which is significantly reduced.