Product Code: ICA13_901

A Study of High Power Fiber-Laser-TIG-Hybrid Welding of Low Alloyed Steel
Authors:
Antti Salminen, Lappeenranta University of Technology; Lappeenranta Finland
Seppo Leppanen, La; Imatra Finland
Presented at ICALEO 2013

The use of laser welding is enlarging to new applications partly via various technological advancements. These include development of lasers and laser system components together with development in process techniques. The first studied and reported of so called laser-hybrid welding processes was laser-TIG-hybrid welding. This process has advantages over the laser-MIG-hybrid process due to the fact that wire feeding and arc parameters can really be controlled separately. This paper examines the suitability of laser-TIG-hybrid-welding process without filler material to welding of 6 mm and 8 mm thick butt welded S355 K2 and Laser 355 MC low alloyed steels. The evaluation of the process was carried out in respect of welding speed, penetration, hardness, the appearance of the weld joints and distortions caused. Laser-TIG-hybrid welds are compared to those of robot-MAG- and manual-MAG welds, in addition to limit values defined by the classes welding standard. With the additional heat provided by the TIG-arc hardness values can be controlled and hardness values below 350 HV can be achieved. The experiments showed almost spatter-free welds with consistent quality also at the root of the weld. Laser-TIG hybrid welding process can be considered to be highly competitive against conventional welding processes.