Micro-macro properties of stainless-clad bimetallic steel welded connections with different configurations

Abstract

This paper aims to investigate the microstructure and mechanical properties of S31603 + Q355B stainless-clad (SC) bimetallic steel welded connections with different welding configurations. A comprehensive research approach was employed, including microstructure analysis, static tensile test, impact test, bending test, Vickers hardness distribution measurement, and analysis of welding economy and efficiency. Four types of welded connections were examined to understand their performance variations arising from different welding configurations. Based on the findings, a recommended welding configuration suitable for structural engineering applications was proposed. Research outcomes showed that the decarburization and carbon accumulation zones were observed at the fusion interface during the welding of dissimilar metals. It should be noted that martensite was formed in the substrate, or the base metal, due to diffusion of alloying elements, with a more pronounced effect observed with higher welding heat inputs. In order to minimize the fusion area of dissimilar metals, it is advisable to avoid using a single welding consumable made of stainless steel as the mechanical properties of the welded connection were not significantly influenced by the use of stainless steel welding consumables with higher Nickle (Ni) and Chromium (Cr) alloying content in the transition region. Consequently, the same welding consumable should be employed in the transition region to simplify the welding procedure and to enhance the welding efficiency.