Optimizing the weld pool geometry in laser welding of AISI 904 L super austenitic stainless steel using multi-input/multi-output grey relational analysis

摘要

Purpose - This study aims to determine the near optimal welding process parameters (beam power (BP), travel speed (TS) and focal position (FP)) using grey relational analysis by simultaneously considering multiple output parameters (depth of penetration and bead width). Further, the optimized parameters were evaluated through the microstructural characterization and hardness measurements across the weld zone.Design/methodology/approach - It is appropriate to apply Taguchi's technique to a complex system like welding process. Therefore, this study is made to determine the near optimal welding process parameters (BP, TS and FP) using grey relational analysis by simultaneously considering multiple output parameters (depth of penetration and bead width).Findings - Taguchi experimental design for determining welding parameters was successful. The hardness of the Argon shielded weld metal was comparatively lesser than the Helium shielded weld metal. The Helium shielded weld metal microstructure comprises of finer grains and higher amounts of equiaxed grains. Argon and Helium shielded weld metal microstructure was endowed with a higher amount of secondary interdendritic austenite phase.Originality/value - The optimal welding conditions were identified in order to increase the productivity and minimize the total operating cost. The process input parameters effect was determined under the optimal welding combinations.