Effects of static magnetic field and hydrostatic pressure on the isothermal martensitic transformation in an Fe-Ni-Cr alloy

Abstract

The effects of static magnetic field and hydrostatic pressure on the isothermal martensitic transformation, whose nose temperature is about 143 K, in an Fe-25.0Ni-4.0Cr alloy (mass%) have been studied by examining the T T T diagrams under those external fields. The static magnetic field makes the nose temperature lower and the incubation time shorter than those under no external magnetic field, while the hydrostatic pressure makes the nose temperature higher and the incubation time longer than those under no external hydrostatic pressure. The shifts of nose temperature and incubation time increase with increasing the strength of those external fields. These results are quite similar to those of a previous Fe-Ni-Mn alloy exhibiting an isothermal martensitic transformation and are well explained by the phenomenological theory previously constructed by the present authors, which gives a unified explanation for the isothermal and athermal processes of martensitic transformations.