Stabilization of the γ Phase upon an Isothermal α-γ Transformation in Fe-Ni Alloys

An experimental study of the effect of the stabilization of the γ phase upon the isothermal α-γ transformation in Fe-Ni alloys with nickel content of 16, 20, and 24% was performed. First, a cycle of heating to 750°C and cooling to room temperature at a rate of 120 K/min was performed. During this cycle, the occurrence of α-γ the transformation upon heating and the γ-α-transformation upon subsequent cooling in the initial state was recorded. After this, the sample was placed into the furnace of the magnetometer preliminarily heated to the temperature of the selected isotherm and, after achievement of the isotherm temperature, was held at this temperature for 1 h. The higher the nickel content in the alloy, the wider the temperature range between the temperature of the onset of the α-γ transformation and the boundary of the two phase field and the higher the thermodynamic stimulus for the redistribution at the temperature of the transformation onset.