Laserstrahl-Unterpulver-Hybridschweißen

Engels, Oliver; Reisgen, Uwe (Thesis advisor); Poprawe, Reinhart (Thesis advisor)

Düren / Shaker Verlag (2020) [Book, Dissertation / PhD Thesis]

Page(s): XV, 147 Seiten : Illustrationen, Diagramme

Abstract

Welding of large plate thicknesses determines the daily production routine in various branches of industry. Welding of linear seams with a length of up to 30 m is a common joining task in the field of tube or pipeline production or also in ship and bridge building. At present, conventional arc welding techniques, such as sub-merged arc welding, are primarily used to manage this joining task. Thus, joining partners with large sheet thicknesses are welded with a constantly high quality level by means of multilayer technology. The Laser Beam Submerged Arc Hybrid Welding Process investigated in this work represents a possible substitution for conventionally used welding processes to increase productivity in the area of large sheet thicknesses. In the context of this work, the formation of the molten pool is investigated in a superordinate manner. Effects are revealed and welding parameters are identified, which lead to the formation of a hybrid welding process. At the beginning of the work the influence of different geometric welding parameters on the welding result is examined. Thus, it is shown that an angle of incidence of the laser beam optics of 15° and of the submerged arc torch of 5° with simultaneously small process distances leads to the formation of a common weld pool. Synergy effects such as the significant increase in welding depth, the absence of weld seam defects despite the large welding depth and a weld seam with homogeneous chemical composition can be documented as a result. In addition, graphic models based on empirical studies are presented, which describe the parameter window that can be used to achieve the highest possible welding depths while maintaining a high degree of quality. In addition, the expansion of the weld pool transversely and longitudinally to the welding direction during the welding process is made visible. For this purpose, the molten material is driven out of the joining zone by means of a gas pressure shock so that a negative image of it is created. In this way, a basic under-standing of the process is created. Finally, it is demonstrated that the welding results achieved up to this point can be transferred to joining partners with joining gaps and to the material quality 1.4301.

Identifier

  • ISBN: 3-8440-7708-1
  • ISBN: 978-3-8440-7708-7
  • REPORT NUMBER: RWTH-2020-11556