High-resolution core and valence band photoemission as well as photoinduced Auger spectra of metallic Sn, polycrystalline SnO and SnO2 ((110) natural single-crystal cassiterite and polycrystalline) samples were measured in order to give information on local electronic and geometric structures around the core-ionized atoms and far providing data for facilitating quantitative analysis of systems containing these species, The SnO surfaces were obtained without the use of ion sputtering by using a special preparation procedure based on in vacuo surface scraping, The respective experimental valence land spectra could be utilized in quantitative analysis of layered tin oxide structures. Valence band spectral shapes are compared to spectra calculated by using a cluster-type (DV-X alpha) MO model. From the Sn Auger parameter measurements, using a simple electrostatic model, the similarity of the initial-state effects for the two oxides was deduced, while the oxygen Auger parameter values indicated large polarizability and the respective final-state hole-hole repulsion energies were determined

Plastic instabilities were investigated by the depth-sensing microhardness test in binary high-purity Al-Mg alloys with different Mg contents. During the tests the applied load was increased from 0 to 2000 mN at constant loading rate. The instabilities appeared as characteristic steps in the load-depth curves during indentation. It was shown that the occurrence and development of the plastic instabilities depend strongly on the solute content. Furthermore, the plastic instabilities occurred only when the solute concentration was larger than a critical value, C 0 . From room-temperature tests on Al-Mg alloys, C 0 was found to be 0.86 wt% Mg. The critical concentration, which is necessary to get plastic instabilities, was also interpreted theoretically.

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The electronic structure of metallic Sn, polycrystalline Sn oxides, and (110) natural single crystal SnO2 (cassiterite) was studied by high resolution measurements of core and valence photoemission, photoinduced Auger spectra, and energy loss spectra. The advantage of in vacuo scraping in obtaining SnO surfaces is shown in comparison with surface cleaning by ion sputtering. Valence band x-ray photoemission spectroscopy spectra are interpreted by a cluster-type discrete variational Xα molecular orbital model, revealing the change in the electronic structure which leads to an increased conductivity. The use of the Auger parameter approach in gaining information on the initial and final state effects, ligand polarizability, and final state hole-hole repulsion energies are demonstrated for the case of tin oxides

High pressure torsion was applied to produce a disk-shaped specimen of Cu60Zr30Ti10 composition. The dependence of the morphology, microstructure, and thermal behavior on the applied shear strain was monitored by scanning and transmission electron microscopies, synchrotron x-ray diffraction, and calorimetry. The disk consists of a gradient microstructure ranging from large homogeneous blocks (about 20 μm) to finely dispersed nanocrystals (about 20 nm) of two stable hexagonal phases and continuously decreasing amorphous content with increasing strain. The evolution of such microstructure was interpreted by using a model based on heat conduction generated by the extensive shear deformation.