Product Code: ICA12_701

Electromagnetic Control of the Weld Pool Dynamics in Partial Penetration Laser Beam Welding of Aluminium Alloys
Authors:
Vjaceslav Avilov, Federal Institute for Materials Research and Testing (BAM); Berlin Germany
André Schneider, Federal Institute for Materials Research and Testing (BAM); Berlin Germany
Marco Lammers, Federal Institute for Materials Research and Testing (BAM); Berlin Germany
Andrey Gumenyuk, Federal Institute for Materials Research and Testing (BAM); Berlin Germany
Michael Rethmeier, Federal Institute for Materials Research and Testing (BAM); Berlin Germany
Presented at ICALEO 2012

An oscillating (AC) magnet field was used to stabilize the surface of the weld pool in bead-on-plate partial penetration 4.4 kW Nd:YAG laser beam welding of AW-5754 plates in PA position. The magnet was mounted on the laser welding head. The magnet field (up to 0.4 T and 10 kHz) was oriented perpendicular the welding direction. Usage of AC magnetic fields results in a significant reduction (up to 50%) of the surface roughness of the welds. The analysis of the weld cross-sections and x-ray images shows a drastic reduction (up to 90%) of porosity contents in the welds. The observed effects can be explained in terms of electromagnetic (EM) contribution to the surface tension (the Garnier-Moreau effect, 1983), as well as the EM induced "Archimedes" forces and the EM stirring flow in the weld pool.