In this article, a model for the estimation of matrix/precipitate interfacial energies is developed. The classic nearest-neighbor broken-bond (NNBB) model is taken as a basis and further developed, to (1) take into account atomic bindings over an arbitrary number of neighboring shells and (2) account for general, multicomponent solid solutions. The model is sufficiently simple and yet reliable for providing estimates of interfacial energies in applications in complex, time-consuming computer simulations of a microstructure/precipitate evolution in which more sophisticated approaches cannot be used. As an example, the model is applied to randomly oriented interfaces in fcc and bcc crystal structures. It is shown that both kinds of crystal interfaces, fcc and bcc, exhibit roughly the same mean interfacial energies, as long as a sufficient number of nearest-neighbor shells is taken into account. A comparison with published experimental and theoretical data on interfacial energies shows good agreement.

A multi-purpose heating attachment designed primarily for X-ray four-circle diffractometers but applicable also for classical powder diffraction is presented. When working in re¯ection geometry, the air-cooled heating stage allows diffraction studies to be performed on plate-like samples up to 1173 K in the whole orientation space. This paper gives a detailed description of the assembly and important technical speci®cations for the performance of experiments. The heating characteristics of the heating stage, the displacement of the sample from the goniometer centre as a result of thermal expansion and the in¯uence of the protecting dome on the diffraction experiment are presented. The simple technical construction, the low weight, the small size and good heating performance make this equipment a general purpose heating attachment for Xray diffraction experiments in re¯ection geometry.

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