Change search
ReferencesLink to record
Permanent link

Direct link
An Experimental and Theoretical Evaluation of Microstructure Coarsening in Duplex Stainless Steels
AB Sandvik Materials Technology.
Outokumpu Stainless Research Foundation.
2013 (English)In: Steel Research International, ISSN 1611-3683, Vol. 84, no 11, 1126-1137 p.Article in journal (Refereed) Published
Abstract [en]

The coarsening of duplex stainless steel microstructures at temperatures above 1000C was investigated experimentally and theoretically. Hot-rolled duplex 2205 and superduplex2507 samples were heat treated isothermally at 1100C up to 700 h, and also between 1000 and 1250C for 24 h. The ferrite content and the microstructure coarseness, quantified by the measured austenite spacing, AS, were evaluated. It was found that theobserved coarsening could be described using Ostwald ripening theory expressed as AS**n-AS0**n=kt, where AS0 is austenite spacing of the as-delivered material, k the rateconstant, n the exponent, and t the heat treatment time. Using regression analysis, n and k were evaluated and the resulting predictions compared with literature theories andresults. The results were also calculated according to the original Lifshitz, Slyozov,Wagner (LSW) theory with parameters taken from literature, as well as with the Dictra software for diffusion and growth in multicomponent systems. The calculations indicated that while the classical LSW theory failed to give a good description of the experimentalresults, the Dictra simulations proved very accurate, even though systems of equal ferrite and austenite content are considerably outside the intended range of applicability of the software.

Place, publisher, year, edition, pages
2013. Vol. 84, no 11, 1126-1137 p.
Keyword [en]
Austenite spacing, Duplex stainless steel, Heat treatment, Microstructure, Ostwald ripening
National Category
Engineering and Technology
URN: urn:nbn:se:kth:diva-121336DOI: 10.1002/srin.201200323ISI: 000328148100007ScopusID: 2-s2.0-84887318813OAI: diva2:618459

QC 20140617. Updated from In press to Published.

Available from: 2013-04-28 Created: 2013-04-28 Last updated: 2014-06-23Bibliographically approved
In thesis
1. Applications of Computational Thermodynamics and Kinetics on Transformations in Stainless Steels
Open this publication in new window or tab >>Applications of Computational Thermodynamics and Kinetics on Transformations in Stainless Steels
2013 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

Stainless steels are high-alloyed, usually with multiple components and often also dual matrix phases, as for duplex stainless steels. This make predictions and calculations of alloying effects on equilibria and transformations complicated. Computational thermodynamics has emerged as an indispensable tool for calculations within these complex systems with predictions of equilibria and precipitation of phases. This thesis offers examples illustrating how computational methods can be applied both to thermodynamics, kinetics and coarsening of stainless steels in order to predict microstructure and, to some extent, also properties. The performance of a current state-of-the-art commercial thermodynamic database was also explored and strengths and weaknesses highlighted.

Place, publisher, year, edition, pages
KTH Royal Institute of Technology, 2013. 60 p.
Stainless Steels, Duplex, Ferrite, Austenite, Computational Thermodynamics, Thermo-Calc, Dictra
National Category
Engineering and Technology
urn:nbn:se:kth:diva-121337 (URN)978-91-7501-714-3 (ISBN)
Public defence
2013-05-16, B2, Brinellvägen 23, KTH, Stockholm, 10:00 (English)

QC 20130429

Available from: 2013-04-29 Created: 2013-04-28 Last updated: 2013-04-29Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full textScopus

Search in DiVA

By author/editor
Wessman, StenHertzman, Staffan
In the same journal
Steel Research International
Engineering and Technology

Search outside of DiVA

GoogleGoogle Scholar
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Altmetric score

Total: 61 hits
ReferencesLink to record
Permanent link

Direct link