The microstructure and phase composition of the high-content Al2O3-Y2O3-doped spark plasma-sintered silicon nitride were investigated. Fully dense silicon nitride ceramics with a typical α-Si3N4 equiaxed structure with average grain size from 200 to 530 nm, high elastic modulus of 288 GPa, and high hardness of 2038 HV were spark plasma sintered (SPSed) at 1550 °C. Silicon nitride with elongated β-Si3N4 grains, higher hardness of 1800 HV, density of 3.25 g/cm3, and Young’s modulus 300 GPa SPSed at 1650 °C was also reviewed.

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The microstructure and physical properties of new Y2O3 and Al2O3 oxide-doped silicon nitride ceramics fabricated by cold isostatic pressing and free sintering were investigated. The phase composition of produced material was also studied by X-ray diffraction at room and elevated temperature. The fabricated ceramics featured a microstructure of Si5AlON7 grains with a fine-grained α-Si3N4 with a small amount of Y2SiAlON5. Described ceramics is attractive for many high-temperature structural applications due to beneficial combination of fine-grained structure with improved mechanical properties and small weight loss.

Sensitivity of one-quasiparticle spectrum of a heavy nucleus to changes of such quantities as equilibrium deformation and pairing-interaction strength is studied. The study is done within a macroscopic-microscopic approach. The analysis is performed on the example of the nucleus 241 Am . Especially large sensitivity of the spectrum to changes of the quadrupole component of the equilibrium deformation is found.

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Research of structure and properties of Cu-Pb-Cu composite interface, obtained by technology of pack rolling of the pair of mutually insoluble metals, was performed using the methods of metallography, micro-and nano-hardness, mechanical tests, energy-dispersion elementary analyses. The work was aimed at the analyses of possible mechanical mechanisms of mass-transfer, determining the hardness of metal joint in conditions of absence of inter-diffusion. It was shown that different intensity of mass transfer of copper and lead takes place through the composite interface, which corresponds to the results obtained on the other system of dissimilar materials-copper-niobium. Qualitative explanation of these patterns was offered on the basis of more intensive plastic flow of fusible compound of the composite in conditions of roll-bond joining.

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