Energetics of the fcc $\left(\gamma \right)$-bcc $\left(\alpha \right)$ lattice transformation by the Bain tetragonal deformation is calculated for both magnetically ordered and paramagnetic (disordered local moment) states of iron. The first-principles computational results manifest a relevance of the magnetic order in a scenario of the $\gamma \text{−}\alpha$ transition and reveal a special role of the Curie temperature of $\alpha \text{-Fe}$, $T_C$, where a character of the transformation is changed. At a cooling down to the temperatures $T<T_C$ one can expect that the transformation is developed as a lattice instability whereas for $T>T_C$ it follows a standard mechanism of creation and growth of an embryo of the new phase. It explains a closeness of $T_C$ to the temperature of start of the martensitic transformation, $M_s$.

The structure state of carbon eutectoid steel has been studied by the in situ neutron diffraction method in the temperature range from room temperature to 800°C. It has been shown that an increase in...

The formation of a short-range order in soft magnetic Fe-Si alloys depending on the annealing temperature has been investigated theoretically and experimentally. The B2-type short-range order has...

In order to determine the mechanism responsible for the formation of short-range order in dilute FeSi solid solutions, the chemical bonding, atomic displacements near the metalloid, and the enthalpy...