Effect of Heat Input on MIG Welding of Martensitic Stainless Steel (Grade 420) for Automotive Manufacturing

The 420 Martensitic Stainless Steel (MSS) is a widely utilized type of steel, particularly in the manufacturing of surgical instruments and machine tools. MIG welding, also known as Gas Metal Arc Welding (GMAW), is a well-established process that is used to join stainless steel materials. In this study, the MIG welding process was performed on 3mm thick 420 MSS work pieces using the same material as filler metal, with the aim of finding the optimized parameters for welding. To achieve this goal, three different levels of welding parameters were used in the experiment. After the welding process was completed, the resulting weld coupons were cut into smaller samples for examination. The geometry of the weld beads was then analysed using a stereo microscope. The findings from this analysis were used to validate the optimized parameters for Wire Arc Additive Manufacturing (WAAM) by following a commonly used rule of thumb for weld bead geometry.