Fiber laser-TIG hybrid welding process of 5083 aluminum alloy

An IPG YLS-6000 fiber laser and a Fronius MagicWave3000job digital welding machine are used in fiber laser-tungsten inert gas (TIG) hybrid welding. The experiment is carried out on the aluminum alloy 5083H116 with a thickness of 4 mm. The effects of characteristic of power source, arc current and distance between heat sources on weld shape of hybrid welding are studied. The welding defect, microhardness and mechanical properties of welded joints are analyzed. The results show that, weld formation is improved while using fiber laser-TIG hybrid welding, especially with variable polarity TIG arc. A good weld can be obtained when the distance between heat sources is less than 4 mm, the arc current is 150 A, and the welding mode is laser leading (LL) arc style. The weld has few pores and no cracks, and the surface is bright and uniform only with a little sag. The tensile strength of hybrid-welded joint is up to 318 MPa, about 93% of base metal, and the joint elongation is 7.6%; both are higher than those in fiber laser welding. The tensile fracture is ductile.