高速列车用A5083P-O铝合金MIG焊热循环分析及残余应力研究  

Research on thermal cycle and residual stress of A5083P-O aluminum alloy MIG welding on high speed train

作　　者：张洪才 吉华[2] 苟国庆[2] 李达[2] 陈辉[2] 

机构地区：[1]铁道部驻青岛机车车辆验收室,山东青岛266000 [2]西南交通大学焊接研究所,四川成都610031

出　　处：《电焊机》2011年第11期30-34,共5页Electric Welding Machine

摘　　要：采用热循环装置对A5083P-O铝合金MIG焊进行热循环测试,并对MIG焊过程温度场和焊接残余应力进行数值模拟。测试结果表明:在焊缝中心处,热循环曲线比较"尖",随着离焊缝中心的距离增加,热循环曲线由"尖"变"钝",加热速度、峰值温度、高温停留时间与时间呈线性变化,而冷却速度变化规律不明显。计算结果表明,在其他焊接工艺参数不变且焊接速度为7.5 mm/s的情况下,当焊接时间为10 s即焊接长度约为75 mm时,焊接温度场进入稳态状态,热循环测试曲线和计算曲线规律一致。残余应力计算结果表明,焊接过程中不均匀的温度场是形成焊接残余应力的主要原因,且小孔法和X射线法测试结果与计算结果基本吻合,规律一致。Thermal cycle parameters of A5083P-O aluminum alloy MIG welding are measured by means of thermal cycle equipment, and temperature field and residual stress are studied by numerical simulation.Measuring results show that in the center of weld bead, thermal cycle curves are ＂shaq＂ and thermal cycle curves will change ＂passivation＂ from ＂sharp＂ when the distance increase from the center of weld bead.The rate of heating,the peak value of temperature and the residence time of high temperature show linear relation with time,while the change tends of cooling rate are not obvious.Measuring results show welding temperature field present steady state when the welding length is about 75 ram.Non-uniform temperature field during welding is the main formation reason of residual stress.The measuring results of hole-drilling method and X-ray diffraction method are, coordinate with results of simulation.

关 键 词：高速列车 5083铝合金 热循环 残余应力 数值模拟 

分 类 号：TG457.14[金属学及工艺—焊接]