Laser welding of thick structural steels

Experiments to determine process conditions for laser welding of thick structural steels are reported. Materials tested were: Domex 355, 460, 600 and 390, high strength, cold forming, microalloyed steels, 8-12 mm thickness; Weldox 960 high strength structural steel, 10 mm thickness; and Hardox 400 wear resistant steel, 10-15 mm thickness. Tests were performed using 12 and 17 kW lasers, with milled or laser cut edge preparation, various butt joint preparations, using autogenous and filler wire welding. Weld shape, microstructure and hardness, torsion fatigue strength, process envelopes for avoidance of solidification defects and laser optics requirements are reported.Godkänd; 2001; 20070104 (ysko