On modification of the internal oxidation and precipitate coarsening theories in the light of Cu-Fe alloy data

Recently the combination of Mossbauer spectroscopy and small-angle X-ray scattering was used to study internal oxidation of Cu-3 at.% Fe monocrystals under Cu2O surface layer at 923-1023 K. The data on oxidation at 923 K are nearly satisfactory described by the Wagner theory, but the data for 1023 K show two orders diminution with respect to the theory predictions. The data on the precipitate (Fe3O4) coarsening at 923 K show seven orders enhancement with respect to the Lifshitz-Slyozov-Wagner theory predictions. Both theories have been modified by taking into account the influence of the stress relaxation induced dislocations on Fe and oxygen solubility and diffusivity in Cu. The data on the stopping of the precipitate coarsening at 973 K and 1023 K have been described by taking into account the elastic stress contribution. The possibility of specific internal oxidation of regions near dislocations by Fe-O cosegregation has been shown.