Effect of a dc magnetic field on the isothermal martensitic transformationin the Fe-24Ni-4Mn alloy

Effects of a de magnetic held ion the isothermal martensitic transformation in the region of the kinetic maximum of the N24G4 alloy and on the martens itic transformation at a liquid-helium temperature were studied. It was sho wn that a de magnetic field markedly affects the isothermal martensitic tra nsformation. In particular, it shifts the temperature range of the martensi tic transformation and the kinetic maximum toward higher temperatures and i nitiates the nucleation of isothermal martensite crystals and their subsequ ent growth upon isothermal holding. A de magnetic field of a sufficiently h i:lh strength causes the intense formation of athermal martensite at the li quid-helium temperature, at which no transformation develops without a magn etic field.