A novel nondestructive layer-by-layer method of chemical analysis that can be realized in an ordinary electron spectrometer is proposed. This method is based on the ionization spectroscopy (IS) and involves two sequential operations: a) collection of a series of experimental IS spectra taken at various primary beam energies; and b) recovering of the true concentration or phase depth profile using a reconstruction procedure that involves a mathematical treatment of these spectra. The proposed method was used to study the behavior of a FeNi 3 (100) alloy at temperatures close to the order-disorder transition temperature (T or ¼ 776 K). Using the reconstruction procedure, an oscillatory concentration profile in ten upper layers of FeNi 3 (100) alloy was obtained. The proposed method was also used in an investigation of the temperature dependence of the composition in the first ten layers of the Co 50 Ni 50 (100) alloy. In the temperature range 900 to 1200 K, the composition of all analyzed surface layers stabilized and remained the same, consisting of pure cobalt in the first layer, with its concentration decreasing in the three underlying layers to 82, 68 and 55 at%, respectively. These results correlate with LEED analysis that also had shown the existence of an hcp Co phase at the Co 50 Ni 50 (100) alloy surface.

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Developed mathematical models of apparent thermal conductivity of porous materials are applied to non-destructive methods of thermal diagnostics. The non-destructive thermal diagnostics of porous materials can be used to estimate the size of pores and cracks in the range 10 −9 to 10 −3 m. A fractal model of porous structure and dependences of thermal conductivity/diffusivity on (experimental) gas pressure are used as a basis for structure parameter calculations. The measuring element (sensor) in this method is the mean free path of gas molecules in pores and cracks (Knudsen number) that is very sensitive to changes in gas pressure. Possible applications of the developed methods include non-destructive thermal diagnostics (NDTD) of nano-and micro-crack sizes; opening, closing and size changes of the cracks at high temperatures in a wide temperature range; evaluation of interfacial and contact heat barrier resistance for coatings; remote laser thermal diagnostics of the cracks; as well as obtaining data on strength, thermal shock behavior, failure and fatigue behavior of coatings and other structures. Examples of several applications of the NDTD method are presented.

The anisotropy of thermal oscillations of atoms in the outermost layers has been studied using LEED. For the first time, data is presented on lateral θ ⊥ s and longitudinal θ ʈ s components of the effective Debye temperature and mean square displacement (MSD) amplitudes (〈U ⊥ 2 〉 and 〈U ʈ 2 〉 are mean square displacement amplitudes of thermal oscillations in the direction normal and parallel to the surface, accordingly) for CoNi 3 alloys. It is suggested, using the present study, that surface segregation in alloys strongly affects the oscillation anisotropy.