Role of stresses and temperature in the <Emphasis Type="Italic">Z</Emphasis> ordering of carbon atoms in the martensite lattice

A numerical solution is given to the equation of the statistical Zener theory of the predominant ordering of carbon atoms in the z sublattice of octahedral interstices of martensite in carbon steels depending on the stress and temperature. It has been found that the external compressive stress applied along the axis of martensite tetragonality decreases the order parameter and that there is a critical value of the stress above which the degree of tetragonality of the lattice falls off jumpwise to zero. Based on the numerical analysis, a discussion of the dependences of the degree of ordering of carbon atoms and the critical stress on the temperature and carbon concentration has been performed.