5083铝合金CMT焊接焊缝质量研究

Study on Welding Quality of CMT Weld Seam of 5083 Aluminum Alloy

采用冷金属过渡焊接技术(CMT)对15 mm厚的5083铝合金板在不同工艺参数下进行焊接试验,对焊缝质量进行了研究。结果表明,在较低的焊接速度和较高预热温度下焊缝气孔少;在较高的焊接速度和较低的预热温度下可以避免角变形等焊接缺陷的发生。利用金相显微镜对显微组织进行观察分析,发现试样的焊接速度低而预热温度高,焊缝处容易形成规则的等轴晶,各个区域的形貌差异更加明显;经过焊接接头硬度分布测试,发现焊缝区显微硬度存在一个最低值,约为50HV。

The welding test of 5083 aluminum alloy plate with a thickness of 15 mm was carried out through cold metal transfer(CMT)welding technology under different process parameters.The quality of weld seam was studied.The results show that the weld seam has less porosities at lower welding speed and higher preheating temperature.Welding defects such as angular deformation can be avoided at higher welding speed and lower preheating temperature.The microstructure was observed by metallographic microscope,it is found that at lower welding speed and higher preheating temperature,regular equiaxed crystals are easy to form at the weld seams.The morphology difference of each area is more obvious.After the test of hardness distribution of welded joints,it is found that there is a minimum microhardness in the weld zone,which is about 50 HV.