Effect of Shielding Gas on the Microstructural Evolution in Laser Beam Welded AISI 410 Martensitic Stainless Steel

摘要

Laser welding of AISI 410 martensitic stainless steel was attempted in a diffusion cooled RF excited CO_2 slab laser under Gaussian mode with argon and nitrogen as shielding gas. The effect of shielding gas and energy density on the resultant weld bead geometry, microstructure and hardness were assessed and discussed. It has been observed that welds obtained under nitrogen shielding conditions had higher and uniform hardness across the weld metal on account of reduced ferrite content.