DIRECT MARTENSITIC TRANSFORMATIONS OF LOW-CARBON STEELS

Abstract

The proposed model is based on the use of the principle of detailed equilibrium, which occurs during phase transitions of the crystal lattice. This theory complements the theory of Landau phase transitions in crystalline media, as well as the theory of crystallization of matter by Kolmogorov and Avrami. In the proposed theory, martensitic transformations are described by equations of induced transitions between two energy levels, which correspond to the number of particles of the original phase with low energy (austenite) and the number of particles of the transformed phase with higher energy (martensite). The source of transformations are particles of the third kind – phonons, the number of which is related to the induced transitions of particles between energy levels and depends on the transformation temperature. The conclusions of the proposed theory quantitatively correspond to the experimental data for phase transformations of low-carbon steels.