Authors:
J. Lamas
Centro Tecnolo´xico do Naval Galego, Ferrol 15590 (A Corun˜a), Spain and Department of TVM, Luleå University of Technology, S-971 87 Luleå, Sweden

J. Karlsson
P. Norman
J. Powell
A. F. H. Kaplan
Department of TVM, Luleå University of Technology, S-971 87 Luleå, Sweden

A. Yan˜ez
Centro de Investigacio´ns Tecnolo´xicas, Universidade da Corun˜a, Ferrol 15403 (A Corun˜a), Spain

Hybrid laser-arc welding has a good tolerance to poor fit up as compared to simple laser welding. For a butt joint, the joint fit-up variations can be reduced to two local properties: the gap width and the vertical edge mismatch. The impact of these two properties on the resulting weld quality has been studied systematically in this paper. The original edges as well as the resulting weld surface topography have been scanned in three dimensions in order to study trends. During hybrid welding, the melt flow and the electric arc were observed at the top surface by high speed imaging to analyze the complex fluid flow phenomena.