Toughness of Duplex Steel Produced by PM-HIP

Toughness of Duplex Steel Produced by PM-HIP

Christoph Broeckmann

download PDF

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.

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


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.

[1] Charles, J.; Verneau, M.; Bonnefois, B.: Some more about duplex stainless steels and their applications; Stainless Steels Proceedings (1996), pp. 97 – 103
[2] Storz, O.: Einfluss der intermetallischen σ-Phase auf die Gebrauchseigenschaften eines ferritisch- austenitschen Duplex-Stahls; PhD thesis Ruhr-University Bochum, Europäischer Univ.-Verlag; 2007
[3] Nilsson, J.-O.: Overview: Super duplex stainless steels; Materials Science and Technology, (1992) 8, Spp 685-700
[4] Bengtsson, B.-O.; Eklund, A.; Del Corso, G.; Scanlon, J.: Material Properties of PM HIP Stainless Steels; Proceedings of PM2010 World Congress; 10.-14.10.2010, Florenz, pp. 541-545
[5] Hämäläinen, E.; Laitinen, A.; Hänninen, H.; Liimatainen, J.: Mechanical properties of powder metallurgy duplex stainless steels; Materials Science and Technology, 2 (1997) 13, pp. 103-109
[6] Broeckmann, C.; Gütthoff, T.; Wünsch, H.; Bengtsson, B. O. B.; Volker, K.-U.: Zähigkeit von Duplexstahl, hergestellt durch Pulver-HIP; in: Kolaska, H. (Hrsg.): Moderne Fertigungsprozesse – Qualität und Produktivität in der Pulvermetallurgie; Tagungsband zum 29. Hagener Symposium, Hagen, 28.-29.11.2013, pp. 123-146
[7] Standard specification for hot isostatically-pressed stainless steel flanges, fittings, valves and parts for high termperature service, ASTM A988/A 988M-07, 2008