Phonon-deformational generalized ginzburg-landau functionals for describing martensite transitions between FCC and BCC structures in metals

A method is developed for theoretical description of martensite transitions between fcc and bcc phases of metals based on generalized Ginzburg-Landau functionals (GGLFs), in which the transformation parameters are the "phonon" parameter describing relative slips of close-packed atomic planes and fcc lattice deformations in the region of a martensite inclusion. General expressions are proposed for calculating the deformational contributions to the GGLF. Local strains and local elastic moduli in the region of martensite inclusions are estimated numerically. The possibility of constructing phenomenological expressions for the GGLF using interpolations of available experimental data on the structure and elastic moduli in the fcc and bcc phases is discussed.