This study investigates the influence of hybrid laser-arc welding parameters on the microstructure and mechanical properties of the weld: namely, influence of welding speed and preheating temperature on the cooling rates, microstructure and hardness. In order to achieve the maximum productivity, optimum welding speed for the hybrid laser-arc welding X80 steel of 14mm thickness with and without preheating was defined

The aim of this research was the experimental investigation of the influence of the gap width and speed of the welding wire on the changes of the geometry in the welded joint in the hybrid laser-arc welding of shipbuilding steel RS E36. The research was divided into three parts. First, in order to understand the influence of the gap width on the welded joint geometry, experimental research was done using continuous wave fiber laser IPG YLS-15000 with arc rectifier VDU-1500DC. The second part involved study of the geometry of the welded joint and hardness test results. Three macrosections from each welded joint were obtained. Influence of the gap width and welding wire speed on the welded joint geometry was researched in the three lines: in the right side of the plates, middle welded joint and in the root welded joint