Study on the Distribution Heterogeneity of Alloy Elements in Laser-GMAW Hybrid Welding

Laser-GMAW hybrid welding was carried on EH36 steel plate to study the effects of relative position of heat source, heat source parameters and laser beam parameters on the distribution of Ni element. The results show that compared with arc leading welding, Ni element distributes more uniformly by laser leading welding. This is because the downward flow trend of the molten pool increases in the welding direction, which promotes the uniform distribution of Ni element. The uniformity of Ni element distribution in the weld increases with the increase of laser beam swing amplitude or frequency. The laser beam swing enhances the mixing effect of the molten pool, and the solidification speed of the weld decreases, therefore, the diffusion and convection of alloy elements in the molten pool can be fully carried out.