Mossbauer study of the ferrite decomposition in unaged duplex stainless steels
- Univ. de Rouen, Mont-Saint-Aignan (France)
Mechanical properties of duplex stainless steels degrade during holding in the temperature range 300--400 C. While no evolution is observed in the austenite, the microstructural evolution of the ferritic phase is the main cause of the embrittlement. Moessbauer spectroscopy is often used to analyze ferrite decomposition above 475 C because it can easily detect {alpha}{prime} domains since there are weakly or non magnetic, whereas {alpha} is magnetic. However, for duplex stainless steels containing both ferrite ({alpha} bcc) and austenite ({gamma} fcc), the paramagnetic {gamma} phase limits the detection of the {alpha}{prime} phase and thus prevents the study of the {alpha}-{alpha}{prime} decomposition. To overcome this problem a method to extract the austenite contribution from the experimental spectrum was developed. As a result, the contribution of {alpha} phase and thus prevents the study of the experimental spectrum was developed. As a result, the contribution of {alpha} phase in experimental spectra can be deduced and the evolution of the {alpha}-{alpha}{prime} decomposition followed. This paper demonstrates that Moessbauer spectroscopy can be extended to the analysis of industrial duplex steels, and that this technique is more accurate than atom probe in characterizing weakly decomposed ferrites.
- OSTI ID:
- 642139
- Journal Information:
- Scripta Materialia, Journal Name: Scripta Materialia Journal Issue: 1 Vol. 39; ISSN 1359-6462; ISSN SCMAF7
- Country of Publication:
- United States
- Language:
- English
Similar Records
Phase transformations in ferrite phase of a duplex stainless steel aged at 500[degree]C
Preferential precipitation site of sigma phase in duplex stainless steel weld metal