镁合金中空薄壁型材的脉冲MIG焊

Study on pulsed MIG welding of AZ31 magnesium alloy hollow thin-walled profiles

采用脉冲MIG焊焊接AZ31镁合金中空薄壁型材,利用光学显微镜(OM)、扫描电子显微镜(SEM)、维氏显微硬度仪、万能拉伸试验机等设备对MIG焊焊接接头的组织和性能进行检测分析。通过一系列的焊接参数实验,得到了表面呈鱼鳞纹状的、连续的、没有表面裂纹和气孔等缺陷的焊接接头。焊缝组织细化,焊接接头的抗拉强度达到母材的90%以上,屈服强度为母材的65%以上,力学性能良好。

Welding of AZ31 magnesium alloy hollow thin-walled profiles is carried out by the Pulsed MIG welding. And the optical microscopy（OM）, scanning electron microscopy （SEM）, Vickers hardness tester, universal tensile test machine and other equipment are used to detect and analyze the microstructure and properties of the welded joints. Finally,we obtained the excellent welded joints with the continuous, and no surface crack free and stoma and other defects of the surface, the texture of the welded joint is refined, the UTS is higher than 90% of the base metal, the yield stress is higher than 65%.The mechanical properties of the joints is in good conditions.