Testing of New Materials and Computer Aided Optimization of Laser Beam Welding of High-Strength Steels

Abstract The objective of this research is to investigate the performance and potential high power laser beam welding of high strength cold resistant low carbon quenched and tempered steel F620W with the use of new computer aided optimization methods. The research was divided into three parts. First, in order to identify the optimal thermal cycle, dilatometric and thermokinetic investigations were performed using a Bahr Thermoanalise DIL 805 dilatometer. To achieve recommended cycle during laser beam welding, the process was simulated using LaserCAD software resulting in optimal process parameters. Based on the simulation results an experiment was performed in bead on plate setup with use of continuous wave fiber laser IPG YLS-10000. Mechanical properties of the weld were studied by subjecting the specimens to a number of destructive tests, namely hardness, tensile strength and impact toughness testing at -40 °C and -60 °C.