The aim of the work is to review the analytical models of austenite decay, taking into account the internal stresses obtained by various authors. It is shown that a common drawback of the known works is the neglect of the effect of the stress-strain state arising during the heat treatment of parts on the kinetics of structural transformations, while the available experimental data indicate a significant effect of stresses and strains on structural transformations. It has been established that the experimental data accumulated to date do not allow reliably describing the effect of the stress state on structural transitions during the heat treatment of steels for the hot deformation tool. A simple theoretical expression is proposed for calculating the amount of martensite formed as a function of the voltage in the γ phase. It is theoretically shown that taking into account the voltage acting in the γ phase leads to an increase in the temperature of the end of the formation of martensite. Experimental study of this effect is especially convenient to carry out in isothermal conditions under uniaxial tension. It is shown that in order to reliably predict the structural state of the hot deformation tool during heat treatment, it is necessary to conduct a comprehensive study related to the experimental study of the effect of stresses on all types of transformations and the creation of an adequate mathematical model of austenite decomposition based on the obtained experimental data.
Structural transformations in the a-tricalcium phosphate powders after mechanical activation and subsequent heat treatment
