Mossbauer and atom probe studies on the ferrite decomposition in duplex stainless steels caused by the quenching rate

The structural and magnetic properties of duplex stainless steels have been studied by conversion electron Mossbauer spectrometry (CEMS) and atom prob e. The results prove that the quenching rate Q is responsible for ferrite e mbrittlement of duplex stainless steels. This embrittlement, due to ferrite decomposition, increases when Q decreases. The Mossbauer spectrometry has been proved to be appropriate to study the early stages of the transformati on. From the hyperfine field distribution of the very decomposed ferrite, t he concentration of the Lu Fe-enriched domains and the alpha' Cr-enriched d omains have been estimated and compared with results obtained by atom probe .