sigma-phase precipitation in stabilized austenitic stainless steels
2000 (English)In: Acta Materialia, ISSN 1359-6454, E-ISSN 1873-2453, Vol. 48, no 10, 2473-2481 p.Article in journal (Refereed) Published
Experimental observations of sigma-phase precipitation in two stabilized austenitic stainless steers, AISI 321 and AISI 347, aged up to 80,000 h at temperatures between 500 and 800 degrees C, are compared with the results obtained from a simple model of the process. The model is based on the assumption that diffusion of alloying elements from inside austenite grains to sigma-phase particles at grain boundaries limits the rate of formation, and this is supported by the presence of zones depleted in chromium at grain boundaries revealed by TEM/EDS. The full multicomponent thermodynamic behaviour of the system is taken into account using the DICTRA software and the influence of grain shape is discussed. The predictions of the model are in fair agreement with experimentally estimated Volume fractions of sigma-phase.
Place, publisher, year, edition, pages
2000. Vol. 48, no 10, 2473-2481 p.
alloys (steels, austenite), phase transformations (nucleation, growth), optical microscopy, transmission electron microscopy (TEM), theory and modelling (diffusion)
IdentifiersURN: urn:nbn:se:kth:diva-20022ISI: 000089196600005OAI: oai:DiVA.org:kth-20022DiVA: diva2:338715
QC 201005252010-08-102010-08-10Bibliographically approved