Papers by Keyword: Ni-Fe-C Alloy

Abstract: Within the framework of the lattice-statics and static fluctuation-waves’ methods, the available energiesof strain-induced interaction of interstitial–interstitial, interstitial–substitutional and substitutional–substitutional impurity atomic pairs are collected and analysed for f.c.c.-(Ni,Fe)–C solutionsallowing for discrete atomic structure of the host-crystal lattice. The lattice spacings, elasticity moduliand/or quasi-elastic force parameters of the host-crystal lattice, and concentration coefficients of thedilatation of solid-solution lattice due to the respective solutes are selected as the input numerical experimentaldata used. The above-mentioned interaction energies prove to have non-monotonically decreasing(‘quasi-oscillating’) and anisotropic dependences on discrete interatomic radius-vector, andthemselves are strong and long-range. In all f.c.c.-(Ni,Fe)-base solutions, there is strain-induced attractionin many co-ordination shells. In general, the strain-induced interaction between impurity atomsin γ-Fe is weaker than in α-Ni (but in some solid solutions, it may prove to be of the same order).The verification of applicability of the approximation of strain-induced interaction of impurities forf.c.c.-(Ni,Fe)–C alloys (by means of analysis of thermodynamic C activity and ‘short-range order’ parametersof C-atoms’ distribution revealed by Mössbauer spectroscopy) showed that it must be supplementedwith additional short-range (‘electrochemical’) repulsion in the first co-ordination shell.Nevertheless, in any case, the strain-induced interaction of impurity atoms must be taken into accountfor analysis of structure and properties of f.c.c.-(Ni,Fe)-base solutions.