Weldability of TWIP and DP steel dissimilar joint by laser arc hybrid welding with austenitic filler

n this paper, an innovative 18% Mn austenitic TWIP steel, which exhibits a very good combination of strength and ductility, was joined by laser arc hybrid welding to a conventional DP steel, which consists of ferrite and martensite obtained by an inter-critical heat treatment and fast cooling. An austenitic filler wire was used to improve the weld strength by avoiding the formation of Mn segregations and improper microstructures in the fusion zone by Mn dilution. Metallographic examinations, microhardness and tensile tests were carried out to assess the effects of the laser and materials interaction on the weldability of TWIP-DP dissimilar welds. Hybrid welding and austenitic filler can have a positive effect on the weldability of the DP-TWIP dissimilar joint