Integrity evolution during dissimilar welding of TWIP steel

Abstract

The integrity evolution induced by manufacturing involving dissimilar TWIP and mild steel weld spots was investigated. Focus was given to the effect of manufacturing parametrization on controlling the dilution of the alloying elements and the resulting weld integrity. Samples manufactured with different conditions were characterized by chemical and phase composition, morphology, and mechanical properties. The findings showed that the distribution of chemical composition and metallurgical features are sensitive to the welding parameters. The influence of manufacturing on weld morphology was noticed. Manganese distribution is affected by the welding cycle, thus leading to austenite destabilization and brittle behavior upon a quasi-static tensile shear strength test. A processing set was proposed to control manganese dilution and martensite transformation.

Keywords

• Dissimilar welding
• Advanced high strength steel
• Mn dilution
• TWIP