Experimental investigations and statistical modelling of dilution rate and area of penetration in submerged arc welding of SS316-L

Abstract

Abstract Submerged arc welding (SAW) is a common welding process which is used in industries such as structural and vessel construction. The advantage of SAW process is, pure weld bead as the weld arc is completely submerged in flux, high deposition rate, and low defect rates and great penetration. It has been reported in prior literatures that it is difficult to control SAW parameters for accurate welding bead. Therefore, in the present work, the attempt has been made to study the effect of various SAW parameters such as welding current, arc voltage and travel speed on area of penetration and dilution rate of weld bead. The experiments were performed on SS 316-L steel alloy. The statistical models were developed to predict the dilution rate and area of penetration in SAW process. The central composite design (CCD) of Response surface methodology (RSM) was used to design the set of experiments. Analysis of variance (ANOVA) was carried out at a confidence interval of 95% to determine the parameters having the significant influence (p less than 0.05) on the responses. The developed models were validated using three confirmatory experiments, and Multi objective genetic algorithm (GA) was used to find the optimum parameters for dilution rate and area of penetration. It was observed that the dilution rate and area of penetration increased with increasing welding current and arc voltage. However, both decreased with increasing the travel speed. The maximum area of penetration was obtained at maximum voltage and minimum travel speed. Optimization revealed that the maximum dilution rate and area of penetration were observed at welding current with 334.068 A, arc voltage 26.70 V and travel speed 13.29 m/hr.