Multi-response optimization and process validation of additively manufactured SS304L depositions by gas metal arc additive process

The present communication analyzes the microhardness and corrosion rate at the interfacial region of additively manufactured SS 304L structure using the gas metal arc additive process. The rationale is to optimize the microhardness and corrosion rate of interfacial region with respect to process factors: travel speed, wire feed rate, arc voltage, and interpass temperature. The experiments have been designed using central-composite-design and optimized using desirability function-based ramp graph. The microhardness was measured using the Vickers method and Corrosion rate was measured by potentiodynamic polarization method. The second-order models of microhardness and corrosion rate were developed verified with analysis of variance. The results conjecture that travel speed significantly influences microhardness, while wire feed rate affects the corrosion rate. The multi-objective optimization to enhance microhardness and minimize corrosion resistance was carried out to ascertain the industrial feasibility. The process parameters were obtained as: 362 mm/min travel speed, 5.5 m/min wire feed rate, 21.2 V arc voltage, and 437 K interpass temperature with respect to the optimum value of microhardness as 231 HV and corrosion rate as 0.035 mm/year and process validated, and recorded 0.43% and 2.77% error for microhardness and the corrosion rate, respectively. Furthermore, optical microscopy, field emission scanning electron microscopy-energy dispersive spectroscopy, and X-ray diffraction were utilized to substantiate the outcomes on microhardness and corrosion behavior. The outcomes of the present study signify the applications of the proposed gas metal arc additive process in industries, where hard and corrosion resistive components are desired.