![]() Thus the evolution of shape changes during precipitate growth in an elastically anisotropic, infinite matrix has been investigated for different two-phase systems. Only by doing so can the resulting microstructure and properties of engineering components be optimized (Abbaschian et al., 2010 ▸ Porter & Easterling, 1982 ▸ Guo & Sha, 2005 ▸). Therefore, it is essential to acquire a fundamental understanding of the effects of developing misfit-strain energies on the thermodynamics and kinetics of phase transformations. ![]() Accordingly, unusual non-equilibrium phenomena can occur: occurrence of metastable phases, non-monotonic variation of transformation rate and unusual morphologies (Thompson et al., 1994 ▸ Biglari et al., 1995 ▸ Sennour & Esnouf, 2003 ▸ Liu et al., 2003 ▸ Meka et al., 2013 ▸ Loewy et al., 2014 ▸ Villa et al., 2014 ▸). The complex interplay of the chemical Gibbs energy change driving solid-state phase transformations and the deformation energy associated with the elastic/plastic accommodation of the misfit of parent and product phases hinders the prediction of the course and the kinetics of phase transformations (Starink et al., 1993 ▸ Mittemeijer, 2010 ▸ Song et al., 2014 ▸). The experimental data are shown to be in good to very good agreement with predictions according to the current treatment.ġ. Introduction: micro- and macrostrains coherent and incoherent diffraction Examples for three types of systems consisting of a matrix with misfitting second-phase particles are dealt with, which differ in the origin of the misfit (precipitation or thermally induced) and in the type of diffraction (coherent or incoherent diffraction of matrix plus second-phase particles). An overview and an (re)interpretation on the above basis is presented of published lattice-parameter data, obtained by X-ray diffraction analyses of aggregates of matrix plus second-phase particles. Formulae for calculation of such misfit-induced lattice-parameter changes are presented for the aggregate (matrix + second-phase particles) and for the individual matrix and second phase, recognizing the occurrence of either coherent or incoherent diffraction by the matrix and second-phase particles. Elastic accommodation of precipitation-induced or thermally induced misfit leads to lattice-parameter changes in crystalline multi-phase systems.
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