Isothermal martensite formation in a magnetically ordered austenite phase of an Fe-32%Ni-0.4%Cr alloy

Abstract

In this study, the isothermal martensitic transformation has been examined in an austenitic Fe-Ni-Cr alloy. The magnetic properties of the austenite phase are investigated with Mossbauer spectroscopy and the results showed that the Fe-32%Ni-0.4%Cr alloy in the austenite state is magnetically ordered. In the austenite state, the six peaks of the ferromagnetic phase of Fe-32%Ni-0.4%Cr alloy were observed in the Mossbauer spectrum. The effective hyperfine field of the ferromagnetic (or antiferromagnetic) austenite phase was determined as 31.9 T and the isomer shift value was determined as -0.19 mm/s. We also investigated the austenite-martensite phase transformation observed upon cooling in the Fe-Ni-Cr alloy by scanning electron microscopy (SEM). (C) 2004 Published by Elsevier B.V.