Toughness of Duplex Steel Produced by PM-HIP

Toughness of Duplex Steel Produced by PM-HIP

Christoph Broeckmann

Abstract. The most important influencing factors for the toughness of duplex steels are being discussed exemplary at grade AISI 318LN. Focus is given to two major aspects: the embrittlement by σ-phase and the embrittlement caused by residual argon pores. While the formation of σ-phase depends on the cooling rate in the HIP vessel, argon porosity can either be caused by insufficient evaporation prior to HIP or small leakages in the capsule. Toughness is discussed in terms of Charpy tests, taking into account the notch radius as additional parameter. The macroscopic results are reflected by investigations of the microstructure. Toughness of PM-HIP steel is compared to appropriate conventionally produced grades.

Keywords
Duplex Steel, PM-HIP, Charpy-Toughness, Argon Content

Published online 2/11/2019, 13 pages
Copyright © 2019 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA

Citation: Christoph Broeckmann, Toughness of Duplex Steel Produced by PM-HIP, Materials Research Proceedings, Vol. 10, pp 169-181, 2019

DOI: http://dx.doi.org/10.21741/9781644900031-23

The article was published as article 23 of the book Hot Isostatic Pressing

Content from this work may be used under the terms of the Creative Commons Attribution 3.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.

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