Reverse martensitic transformation and resulting microstructure in a cold rolled metastable austenitic stainless steel
2008 (English)In: Steel Research International, ISSN 1611-3683, Vol. 79, no 6, 433-439 p.Article in journal (Refereed) Published
The reverse martensitic transformation in cold-rolled metastable austenitic stainless steel has been investigated via heat treatments performed for various temperatures and times. The microstructural evolution was evaluated by differential scanning calorimetry, X-ray diffraction and microscopy. Upon heat treatment, both diffusionless and diffusion-controlled mechanisms determine the final microstructure. The diffusion reversion from alpha '-martensite to austenite was found to be activated at about 450 circle C and the shear reversion is activated at higher temperatures with A(f)' similar to 600 circle C. The resulting microstructure for isothermal heat treatment at 650 circle C was austenitic, which inherits the alpha '-martensite lath morphology and is highly faulted. For isothermal heat treatments at temperatures above 700 circle C the faulted austenite was able to recrystallize and new austenite grains with a low defect density were formed. In addition, carbo-nitride precipitation was observed for samples heat treated at these temperatures, which leads to an increasing M(s)-temperature and new alpha '-martensite formation upon cooling.
Place, publisher, year, edition, pages
2008. Vol. 79, no 6, 433-439 p.
Metallurgy and Metallic Materials
IdentifiersURN: urn:nbn:se:kth:diva-86079DOI: 10.2374/SRI08SP039-79-2008-433ISI: 000257357500005OAI: oai:DiVA.org:kth-86079DiVA: diva2:503775
QC 201202292012-02-162012-02-132012-02-29Bibliographically approved