Nanostructure evolution and mechanical property changes during aging of a super duplex stainless steel at 300°C
Artikel i vetenskaplig tidskrift, 2015

The nanostructure evolution and the corresponding changes in mechanical properties of a super duplex stainless steel 2507 (UNS S32750) during aging at 300. °C up to 12,000. h have been investigated. Microstructural studies using transmission electron microscopy and atom probe tomography show that subtle Cr concentration fluctuations develop during aging. The amplitude of the concentration fluctuations is proportional to the hardness of the ferrite phase, and it is also proportional to the decrease in room temperature impact toughness during aging. The fracture behaviour of the alloy changes gradually from ductile to cleavage fracture, upon aging. The cracks were found to propagate through the ferrite phase, partly along deformation twin interfaces, and delamination between the austenite and ferrite phases was observed.

Atom probe tomography (APT)

Phase separation

Mechanical properties

Transmission electron microscopy (TEM)

Duplex stainless steel

Spinodal decomposition


N. Pettersson


S. Wessman


Mattias Thuvander

Chalmers, Teknisk fysik, Materialens mikrostruktur

P. Hedström

Kungliga Tekniska Högskolan (KTH)

J. Odqvist

Kungliga Tekniska Högskolan (KTH)

R.F.A. Pettersson


S. Hertzman

Outokumpu Stainless Research Foundation

Materials Science & Engineering A: Structural Materials: Properties, Microstructure and Processing

0921-5093 (ISSN)

Vol. 647 241-248


Metallurgi och metalliska material



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