薄板铝合金的CMT焊接工艺

为了解决利用传统焊接方法焊接铝合金时容易造成生产效率低、焊接变形大以及夹钨、裂纹、气孔等缺陷,对6082-T6铝合金进行了冷金属过渡焊,并确定了最佳焊接工艺参数.利用金相显微镜、扫描电子显微镜、能谱分析仪和X射线衍射仪对铝合金的焊缝成型、显微组织与相组成进行了分析.利用维氏显微硬度计和万能拉伸试验机测量了焊接接头的硬度和拉伸力学性能.结果表明,在最佳焊接工艺参数下6082-T6铝合金焊缝成型良好,其焊缝组织主要由α-Al固溶体组成.焊接接头的拉伸断裂位置处于热影响区,其最高拉伸强度约为母材的61%,拉伸断口形貌为塑性断口.

CMT welding technology for aluminum alloy sheet

In order to avoid such disadvantages as low production efficiency, large welding distortion, tungsten inclusion, cracks and porosity when the aluminum alloy was welded with the traditional welding methods, the cold metal transition(CMT)welding for the 6082-T6 aluminum alloy was carried out, and the optimum welding parameters were determined. The weld formation, microstructure and phase constitute of aluminum alloy were studied with the optical microscope(OM), scanning electron microscope(SEM), energy dispersive spectrometer(EDS)and X ray diffractometer(XRD). The hardness and tensile properties of welded joint were measured with the microhardness tester and universal tensile testing machine. The results show that under the optimum technological parameters, the 6082-T6 aluminum alloy exhibits good ability of weld formation, and the microstructure of weld line is mainly composed of α-Al solid solution. The tensile fracture location of welded joint is at the heat affected zone, the highest ultimate tensile strength is about 61% as that of base metal, and the tensile fracture morphology is ductile fracture.