Multi objective optimization of welding parameters using Taguchi based grey relation analysis in activated TIG(ATIG) welding on SAF2507 super duplex stainless steel

In this investigation the effect of ATIG welding process parameters in welding Super duplex stainless steel (SAF2507) on its aspect ratio and the depth of penetration were studied and optimised using Taguchi based grey relational analysis L16 orthogonal array (OA). The significant ATIG input process parameters considered are welding current, welding speed, arc gap and gas flow rate. The quality characteristic for the depth of penetration is to be maximised while the aspect ratio (ASR) has to be minimised. The macro structure and the microstructure are captured to study the metallurgical changes that happens during the changes in the process parameters. ANOVA is performed to find the effect of significant process parameter on the response. The welding speed plays a major role in affecting the depth of penetration and the aspect ratio in multi objective optimization. The confirmation run is conducted by setting the levels of the parameter at the optimum levels to determine the optimum penetration and the aspect ratio of the joints.