Mathematical modeling of phase transformations in steels during thermomechanical loading

In steels all known solid state phase transformations are observed: polymorphic transformation with wide spectrum of morphological and kinetics features, eutectoid decomposition (pearlite transformation), decomposition of supersaturated solid solutions, short- and long - range ordering in austenite and martensite. The important feature of these systems is different diffusion mobility of metal and carbon atoms. Therefore, reorientation of the crystal lattice may occur simultaneously with the diffusion redistribution of carbon and alloying elements. In the context of equilibrium thermodynamics of concentration non-uniform systems is investigated microstructure evolution in steels during thermo-mechanical loading. Also features of solid state are taken into account. Strong inter-atomic transformation is the causes of elastic stress and various relaxation mechanisms that influence on shape, orientation and structure of new phase.