Solidification cracking in laser GMA hybrid welding of thick-walled parts

Abstract

Laser GMA hybrid welds, producing partial penetration, were conducted on stiff tubes made of S460NH. Experiments, using a design-of-experiments plan were conducted to examine the influence of the welding parameters on the occurrence of solidification cracks. Results say that cracks diminish, when high levels of arc power are applied, while their number increases with rising laser beam power. The weld velocity had no measurable impact.

Keywords:

• Laser hybrid welding
• Solidification cracking
• Partial penetration welding
• Tube welding
• Thick walled parts
• Design of experiments

Acknowledgements

The IGF research project 15·917 N Laser-MSG-Hybridschweißen dickwandiger Präzisionsrohre (‘Laser-GMA-hybrid welding of thick-walled high-precision tubes’) of the research coalition ‘Forschungsvereinigung Schweißen und verwandte Verfahren des DVS, Aachener Str. 172, 40223 Düsseldorf’ was funded via the AiF within the program for the promotion of industrial research collaboration (IGF) by the Federal Ministry of Economics and Technology (BMWi) on behalf of an enactment by the German Bundestag.