Optimization Of Process Parameters For The A-Tig Welding Of Inconel 617 Using Particle Swarm Optimization And Genetic Algorithm

Inconel 617 alloy has been included in the boiler and pressure vessel (BPV) code of the American society of mechanical engineers (ASME) for its effectiveness in nuclear applications due to its ability to maintain strength at elevated temperatures. This study is based on the optimization of process parameters for activated flux tungsten inert gas (A-TIG) welding of 10-mm thick Inconel 617 material. Process parameters considered in this study include weld current (A), weld torch travel speed (mm/min), arc gap (mm) and flux powder (silicon dioxide (SiO2) and titanium dioxide (TiO2)) combination. The bead on plate welding experiment was carried out by varying the combination of process parameters in each experimental trial. The Taguchi L16 orthogonal array was the design matrix used for the design of experiments (DOE). In the bead on plate welding experiment, a total of 16 experimental trials, each having a different set of process parameters was conducted. The weld bead samples corresponding to each trial were prepared for measurement of the responses which were measured from each of the 16 weld bead samples and included depth of penetration (DOP), bead width (BW), depth to width ratio (DWR), weld cross-sectional area (WA), and bead height (BH). The objective of this work was to maximize DOP, DWR, WA, BH and minimize BW. Analysis of variance (ANOVA) was used to identify the significance of process parameters. Optimization techniques including particle swarm optimization (PSO) and genetic algorithm (GA) were used in the study. The optimized process parameters and optimal solutions attained from each optimization technique were compared. It was found from the study that weld current was the most significant process parameter for all responses followed by weld torch travel speed, flux powder combination and arc gap. Optimal process parameters to achieve maximum DOP, DWR and WA were found to be weld current of 290 A, weld torch travel speed of 50mm/min along with an arc gap of 1mm and 100% TiO2 as flux. The optimal solution for DOP, DWR and WA was found to be 7.04mm, 0.437 and 7.619mm2 respectively. The optimal solution for BW and BH was 6.302 and 0.677mm, respectively. A confirmation test was conducted to validate the optimal solution obtained from this study. The results from the confirmation test agreed with the solution obtained by optimization techniques.