Multi Response Optimization of Welding and Tempering Parameters of 10 mm Thick Dissimilar Sheet Steels

Abstract

The effect of technological parameters of gas metal arc welding with SG2 electrode wire and subsequent tempering on the structure and mechanical properties of multi-pass welded joints from dissimilar sheet steels St37-2 and St52-3 with a thickness of 10 mm has been studied. To optimize the technological conditions of welding and heat treatment during the experiments, a systematic approach with three level variables of parameters for the Taguchi orthogonal array was used, where mechanical properties (tensile tests, hardness and impact strength) and microstructural characteristics (optical metallography, SEM, XRD) are investigated. The contribution of each welding and tempering variable was evaluated, and optimized with Grey relational analysis. It was found that that changing the arc voltage during welding has the greatest impact on the mechanical properties, and the tempering process after welding increases the plastic characteristics of welded joints.