Influences of laser on the energy parameters of the electric arc in the case of laser-MIG hybrid welding

Abstract

Abstract The work presented in this paper deals with the relationship between the laser and the electric arc during welding and chamfer filling operations using the hybrid laser welding process. This unconventional welding process requires perfect mastery, in order to increase the productivity and quality of welds, especially in nuclear facilities. Mastering the hybrid process involves a phase of understanding the phenomena involved in a welding operation. To better understand the role of each process in the combination of laser and MIG, we carried out a laser-only and MIG-only tests using the same operating parameters as those used in hybrid welding. Test results show that the laser preheats the surface, with some of the energy deposited on the side walls of the chamfer. The role of MIG is to deposit metal to fill the chamfer. We can therefore consider that its main role is to provide a volumetric energy deposit. Using the experimental design, we studied the influence of five parameters such as wire speed, distance between the laser and the MIG, welding speed, laser power and laser defocusing on the power of the MIG. The results show that the interaction between laser power and wire speed has the greatest effect on arc power, followed by wire speed and other interactions. To verify the arc energy values given by the FRONIUS generator, we carried out additional measurements using a SEFRAM device. The results measured by FRONIUS are always higher than those of SEFRAM. Both series of measurements follow the same variations.