TY - JOUR A1 - Gebhardt, Moritz Oliver A1 - Gumenyuk, Andrey A1 - Quiroz Penaranda, Vanessa A1 - Rethmeier, Michael T1 - Laser/GMA hybrid welding of thick-walled precision pipes JF - Welding and cutting N2 - Thick-walled pipes made of steel are the basis of a large number of components in mechanical and installation engineering, e.g. for hydraulic components, in power station technology or in the petroleum industry. Particularly when strict positional and shape tolerances are demanded, the classical manufacturing process is chip-producing machining from the solid material. However, this is time-intensive and material-intensive. The laser/GMA hybrid processes with modern high-power lasers are a suitable alternative. With these processes, it is currently possible to weld components with a wall thickness up to approx. 15 mm with little distortion in one pass. However, in initial experiments, solidification cracks with longitudinal and vertical orientations in relation to the welding direction, so-called central line cracks, were established in welds on pipes. Within the framework of a research project, it was possible to determine the cause of the cracking and to find measures in order to avoid it. The technical boundary conditions could be complied with in this respect. The article gives an overview of the research project and the essential results. PY - 2012 SN - 1612-3433 VL - 11 IS - 5 SP - 312 EP - 318 PB - DVS - German Welding Society CY - Düsseldorf AN - OPUS4-26912 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -