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The method of electron beam heating of a mixture of yttrium and zirconium oxides for the synthesis of complex oxides has been implemented. It is established that the applied technology of melting the mixture of oxides leads to the formation of fluorite phases. It is determined that homogenization of the initial mixture of oxides should be carried out in a high-energy mill, which will reduce the temperature and duration of the synthesis of complex oxide compounds, including the desired structure of pyrochlorine. It is proposed to improve the technique of intensive thermal influence on the process of pyrochlorine synthesis by using an equiatomic alloy Y-Ti (65 wt.% Y-35 wt% Ti), which has been smelted using the arc melting method in an argon atmosphere. It was found that hydrogen saturation reduces the efficiency of pyrochlorine synthesis and increases the grain size, which may be associated with grain growth at the stage of hydrogen saturation. [ABSTRACT FROM AUTHOR]

The paper presents a study of interdiffusion processes in a binary Fe-Ni system (obtained by elec-troconsolidation of nickel and iron powders) by X-ray energy dispersive spectroscopy. Well-separated regions of almost pure iron and nickel have been discovered. The content of nickel, estimated from the concentration dependence of the interdiffusion coefficient, which determines the kinetics of the ho-mogenization process of the electroconsolidated Fe-Ni composite sample, was ≈ 70 at.%. The value of the interdiffusion coefficient of the electroconsolidated Fe-Ni composite is significantly higher than that of the alloy of similar composition which probably results from the effect of spark plasma sintering technology (pressure and current along the same direction during consolidation) but also from a significant contribution of diffusion with mass transfer along the particle boundaries in the composite. [ABSTRACT FROM AUTHOR]

Chromium oxide ceramics may be considered as a new generation of ceramic materials for cutting tools with considerably improved high speed cutting performance. The present work is focused on the development of Cr2O3 nanocomposite materials fabricated with the Field Activated Sintering Technique (FAST). The main objective of the proposed work is to study the influence of electric field on the densification process during FAST sintering of the materials in the Cr2O3-AlN system with nanosize microstructure. Additional objectives are to characterize mechanical properties of the obtained Cr2O3 ceramics. The work aimed to develop composite materials based on Cr2O3-based nanoparticles for cutting, then to check their cutting properties and to work out the recommendations for their use for processing of various materials, accordingly. [ABSTRACT FROM AUTHOR]

The electrical and thermal conductivity of the sample containing 97% by volume of the Ti3AlC2 MAX phase and 3% volume TiC was experimentally studied in the temperature range 15-300 K. The temperature dependence of the electrical resistance is approximated by a relation that takes into account the scattering of electrons by phonons and defects. The temperature dependence of the thermal conductivity shows a maximum at about 75 K. In the region of elastic scattering of electrons, the phonon and electron heat transfer are separated. With increasing temperature, the fraction of phonon heat transfer decreases from ∼90% at low temperatures to ∼40% near room temperature. [ABSTRACT FROM AUTHOR]