夹具约束对铝合金薄板焊接变形的影响

zsc19751013

夹具约束对铝合金薄板焊接变形的影响

ftgzqun

摘要： 采用热弹塑性有限元技术对不同夹具拘束情况下铝合金薄板焊接过程进行了数值模拟,并利用脉冲氩弧焊接工艺、不同的夹具布置形式,研究了厚度为5 mm铝合金薄板构件的挠曲变形.结果表明,冷却过程中夹具对焊缝附近的塑性变形区的收缩等效于反向拉伸,可减小纵向残余塑性应变,因此利用夹具的拘束作用可以控制和减小铝合金薄板焊接残余应力和变形,但夹具对焊缝及附近区域的拘束程度不同,控制焊接变形的效果也不同.采用合理的夹具布置可以将薄板的纵向残余挠度控制在1 mm左右.
Abstract： The three-dimensional numerical simulation of welding process for aluminum alloy thin plate under the conditions of different clampings was performed by means of thermal-elastic-plastic FEM technology, and the longitudinal flexibility in thickness of 5 mm aluminum alloy thin plate was investigated using pulsed TIG welding technology and different clamp arrangements. The results show that there is an tensile action on welding plasticity zone in cooling process, and residual longitudinal plastic strain is reduced. Therefore, residual welding stress and distortion can be controlled and reduced. However, effects of reducing welding distortion are different with the changes of constrainment of clamps on weld zone. The residual longitudinal flexibility in aluminum alloy thin plate can be controlled in the range of 1 mm.