Study of welding parameters’ effects on residual stress and hardness in 316 stainless steel pipes: Experimental and analytical investigations

Abstract During service, residual stresses are generated as a result of plastic deformation induced by mechanical loads, thermal loads, or variations in the applied welding. Despite extensive research on welding processes, there remains a significant gap in understanding the combined effects of different welding parameters on the residual stresses and hardness of welded 316 stainless steel pipes. This study addresses this gap by systematically examining parameters of welding currents (90, 100, 110, 120, 140, and 160A), metal wire types (6010, 6013, and 7018), and wire diameters (3.2 and 2.25 mm), to provide a comprehensive analysis of their impact on mechanical properties. As part of the experimental work, arc welding, hardness tests, and X-ray diffraction tests were conducted. In different welding conditions, residual stresses increase as the hardness decreases, according to theoretical calculations based on X-ray diffraction analysis. It is observed that as residual stresses increase, hardness levels decrease, providing valuable insight into the relationship between these factors. In this systematic investigation, existing knowledge is extended.