温差拉伸控制铝合金薄板的焊接变形

对两种形式的温差拉伸控制铝合金薄板焊接残余变形的效果和规律进行了研究。研究表明，由随焊激冷造成的动态温差拉伸减小焊接变形的效果受夹具自身散热条件的影响较大：不采用整体预热时，难以造成马鞍形温度场，此时减小焊接变形的机理主要是焊接线能量的等效降低；采用整体预热后，能够造成一定程度的温差拉伸，减小焊接变形的效果明显提高。中间冷却两侧加热的静态温差拉伸能够造成显著的马鞍形温度场，充分发挥温差拉伸的作用，

Control of Welding Distortion in Thin Aluminum Alloy Plate by Thermal Tensioning

The effects of distortion control in welding thin aluminum alloy plates by two kinds of thermal tensioning were investigated.It is shown that the effect of dynamic thermal tensioning by trailing intensive cooling is greatly influenced by the heat-dissipating conditions of the fixtures.Without uniform preheating it is difficult for trailing intensive cooling alone to create a saddle-shaped temperature field and the mechanism of reducing distortion is equivalent to the decrease of welding heat input. While combined with uniform preheating ,dynamic thermal tensioning comes into being to some degree and the effect of reducing distortion increases obviously.Static thermal tentioning can create a remarkable saddle-shaped temperature field and reduce welding distortion effectively.The minimum welding distortion was obtained by the combination of static and dynamic thermal tensioning.