低熔点锌铝合金脉冲激光焊接工艺研究

Study on the Process of Pulsed Laser Welding of Super-Eutectic ZA Alloy

研究了锌铝合金的脉冲激光焊接,讨论了焊缝中典型焊接缺陷的形成机理。通过光学显微镜研究了接头中的显微组织分布规律,并通过焊缝表面成形及拉伸试验评估了接头的力学性能。结果表明:在合适的工艺参数条件下可以获得良好的焊缝成形,接头的抗拉强度为105MPa,可以达到母材的62%。焊缝区的主要组织为初生η相(白色枝晶组织)、β相(η相周围的块状组织)和(β+η)共晶组织(片状组织)。

In this paper,we described pulsed laser welding of super-eutectic ZA alloy and discussed the mechanism of typical welding defects.The microstructure was investigated using an optical microscope and the mechanical properties of welded jointswere evaluated by means of theweld surface formation and tensile test.The results showed that a good joint can be achieved under theproper technical parameters.The tensile strength of welded joints was up to 105 MPa,62% of that of the base metal.The microstructure in the weld consistedof primaryηphase（white dendritic structure）,βphase（a black blocky distribution aroundηphase）,and eutectic phases（β＋η）（platy layer）.