Кинетика структурных фазовых переходов в сплаве Fe-=SUB=-80.5-=/SUB=-Ga-=SUB=-19.5-=/SUB=-

Abstract

This work is devoted to the Monte Carlo simulation of the kinetics of phase transitions of the order-disorder type in the Fe80.5Ga19.5 alloy using the Blume-Emery-Griffiths Hamiltonian. The study of phase transformations was carried out in two stages: (1) different cooling rates (different number of Monte Carlo steps at a constant value of the binding energy); (2) isothermal annealing (the binding energy depends on the number of Monte Carlo steps at a fixed temperature). In the first case, a high cooling rate leads to one phase transition A2-> D03 + A2 at 700oС, while slow cooling leads to a transition A2-> D03 + A2 at 700oС through a mixture of phases A2, D03, B2 and L12 in the temperature range from 850 to 700oС. In the second case, an increase in the volume fraction of the L12 phase is shown with an increase in the duration of annealing at 750oС. Based on the data obtained, a thermokinetic diagram of phase transformations was constructed.