Abstract: In order to study the performance of YAG-MIG(metallic inert gas)arc hybrid welding joint of ZL-114A aluminum alloy,the tensile test and scanning electronic microscope were adopted to analyze the mechanical properties and microstructure of welded joint.The microstructure of the bead was smaller than that of base metal because of the inherent splat cooling of welding and the beneficial effect of titanium(Ti),and the microstructure was smaller when the heat input was smaller.The crystal of heat affected zone(HAZ) was coursing,and had a softened zone near the bond line because of the precipitation and dissolution of the solid solution phase in base metal.The softened zone was the worst mechanics in the joint,which in the YAG-MIG hybrid welding was usually much narrower than that in the single MIG welding.The tensile-strength of the YAG-MIG hybrid welding joint was up to 80% of the base metal,In order to study the performance of YAG-MIG(metallic inert gas)arc hybrid welding joint of ZL-114A aluminum alloy,the tensile test and scanning electronic microscope were adopted to analyze the mechanical properties and microstructure of welded joint.The microstructure of the bead was smaller than that of base metal because of the inherent splat cooling of welding and the beneficial effect of titanium(Ti),and the microstructure was smaller when the heat input was smaller.The crystal of heat affected zone(HAZ) was coursing,and had a softened zone near the bond line because of the precipitation and dissolution of the solid solution phase in base metal.The softened zone was the worst mechanics in the joint,which in the YAG-MIG hybrid welding was usually much narrower than that in the single MIG welding.The tensile-strength of the YAG-MIG hybrid welding joint was up to 80% of the base metal,the fracture characteristic belonged to brittle fracture.The results show that the high quality joint can be achieved in a high welding speed when the welding parameter is appropriate,so the YAG-MIG hybrid welding is an ideal welding technique for aluminum alloy with high efficiency.the fracture characteristic belonged to brittle fracture.The results show that the high quality joint can be achieved in a high welding speed when the welding parameter is appropriate,so the YAG-MIG hybrid welding is an ideal welding technique for aluminum alloy with high efficiency.