热输入对热挤压AZ61镁合金钨极氩弧焊焊缝中第二相的影响

摘要

采用钨极氩弧焊对热挤压AZ61镁合金在不同热输入量下进行焊接,分析了热输入对焊接接头焊缝中平均晶粒尺寸及第二相的影响.结果表明:随热输入的增加,第二相β-MgnAl2增多；当热输入从26.0J·mm-1增大至45.5J·mm-1时,焊缝平均晶粒尺寸从10μm增大至17μm,第二相β-Mg17Al12在焊缝区的面积分数由11.2％增大至13.9％.%AZ61 magnesium alloy was welded by gas(argon) tungsten-arc welding (GTAW) process at different heat inputs,the effects of heat input on the average grain size and second phase in weld seam zone of the welded joint were analysed.The results show that the second phase β-Mg17Al12 increased with the incresse of heat input.When the welding heat input increased from 26.0 J · mm-1 to 45.5 J ·mm-1,the average grains size in weld seam zone increased from 10 μm to 17 μm,and the area percentage of the second phase β-Mg17Al12 increased from 11.2 ％ to 13.9 ％.