Laser-GMA hybrid welding of direct quenched steel in lap joint configuration - A preliminary study

Welding experiments using laser-GMA hybrid welding of lap joint between 6.5 mm thick direct quenched Ramor 500 grade protection steel and 2 mm thick Optim 500 MC construction steel plates were carried out. The filler materials used were Union Thermanit X96 and Esab OK Autrod AISI 316LSi wire. Direct quenched Ramor 500 grade steel can be used e.g. as an armour plating applications because it possess excellent ballistic properties combined with high strength and hardness [1]. However, joining of above material by welding can be challenging because of local softening at heat affected zone regions. The aim was to evaluate feasibility of hybrid welding process in joining point of view and to evaluate base and filler material weldability concerning e.g. hardness distribution across the weld cross-section. Also dilution assessments were made using EDS measurements in order to reveal how base and filler material is distributed across the weld cross-section.