Concurrent phase separation and clustering in the ferrite phase during low temperature stress aging of duplex stainless steel weldments
Journal article, 2012

The concurrent phase separation and clustering of alloying elements in the ferrite phase of duplex stainless steel weldments after stress aging at 325 degrees C have been investigated by atom probe tomography analysis. Both phase separation, into Fe-rich and Cr-rich ferrite, and solute clustering were observed. Phase separation in the heat-affected zone (HAZ) is most pronounced in the high alloyed SAF 2507, followed by SAF 2205 and SAF 2304. Moreover Cu clustering was observed in the HAZ of SAF 2507. However, decomposition in the weld bead (25.10.4L) was more pronounced than in the HAZs, with both phase separation and clustering of Ni-Mn-Si-Cu. The observed differences in the decomposition behaviors in the HAZ and weld bead can be attributed to the high Ni content and the characteristic microstructure of the weld bead with high internal strains. In addition, an applied tensile stress during aging of weldments has been found to further promote the kinetics of phase separation and clustering.

Phase separation

spinodal decomposition

fe-cr system



Spinodal decomposition

Atom probe tomography


Duplex stainless steels




J. Zhou

Royal Institute of Technology (KTH)

J. Odqvist

Royal Institute of Technology (KTH)


Mattias Thuvander

Chalmers, Applied Physics, Materials Microstructure

Chalmers, Applied Physics, Microscopy and Microanalysis

S. Hertzman

Outokumpu Stainless Research Foundation

Royal Institute of Technology (KTH)

P. Hedstrom

Royal Institute of Technology (KTH)

Acta Materialia

1359-6454 (ISSN)

Vol. 60 16 5818-5827

Subject Categories

Materials Engineering



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9/6/2018 1