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Welding in the World

, Volume 62, Issue 4, pp 811–817 | Cite as

Investigation on a creep-tested CB2 steel cross-weld sample welded with a matching flux-cored wire

  • S. Baumgartner
  • H. Pahr
  • T. Zauchner
Research Paper

Abstract

Heavy cast components like steam turbine or valve casings made of GX13CrMoCoVNbNB9-2-1 (CB2 steel) are used in modern fossil-fired power plants for service temperatures up to 620 °C. For production welding of these huge components, high productivity and good out-of-position weldability are needed. To combine these requirements, flux-cored arc welding is a preferred welding process. A matching flux-cored wire consumable has been developed, which offers sufficient short-term mechanical properties at ambient temperature. To prove weld metal long-term properties at service temperature, uniaxial creep rupture tests at 625 °C have been started several years ago. The microstructure of a cross-weld sample, ruptured in the heat-affected zone, was investigated by light optical microscopy and scanning electron microscopy with energy dispersive X-ray analyses. Area fraction and mean radius of precipitated Laves phase and M23C6 carbides were compared to the results of MatCalc™ simulations.

Keywords

Mechanical properties Creep-resisting materials Welded joints Cored filler wire GMA welding 

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Copyright information

© International Institute of Welding 2018

Authors and Affiliations

  1. 1.voestalpine Böhler Welding Austria GmbHKapfenbergAustria

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