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In this work, the characteristics of the structure, hardness, elasticity, and cavitation resistance of the material of Ti2AlC MAX phase cathodes manufactured by hot pressing, as well as ion-plasma coatings deposited using these cathodes on titanium alloy Ti6Al4V, have been studied. It was found that the cathode material, which contains 83 wt. % MAX phase Ti2AlC, is characterized by a hardness of 10 GPa, a H/E value of 0.04, and low cavitation resistance. The average cavitation wear of the cathode is 4 times higher than that of the titanium alloy Ti6Al4V. It was found that the elemental and phase composition of the obtained coatings differs from the composition of the cathode. The main phase in the coatings is nanocrystalline carbide (Ti, Al) C with a cubic structure of the NaCl type. Ti0.58Al0.17C0.25 coatings deposited by ion sputtering using an arc gas plasma source are characterized by a hardness of 21 GPa. The hardness of vacuum-arc coating Ti0.65Al0.07C0.28 is closer to the hardness of the cathode – 13 GPa, which is due to the presence of α-Ti in its composition. The H/E ratio of the coatings is 1.5 times higher than that of the cathode, which is a prerequisite for high cavitation resistance. The average rate of cavitation wear of vacuum arc coating Ti0.65Al0.07C0.28 is 1.5 times lower than that of the vacuum arc coating TiN and 3 times lower than that of the uncoated Ti6Al4V alloy. [ABSTRACT FROM AUTHOR]

The effects of the additions of powdered titanium carbide (TiC) and polyvalent titanium oxides (Ti-O) to MgB2 (synthesized under high pressure (2 GPa)-high temperature (800 and 1050 °C) conditions) on the critical current density, jc, criticalmagnetic fields, BC2 and Birr, and the related transformations in the materials structures are reported in this paper. The superconducting characteristics are compared with that of MgB2 with titanium (Ti) additions synthesized under the same conditions. The synthesis temperature, the ability of Ti-containing compounds to act as a getter, and the different diffusion rates of Mg and B into grains of these additions influence the distribution of the elements (boron, magnesium, and impurity oxygen) in the structures ofMgB2-based materials. This in turn affects the formation of pinning centers, the resulting flux pinning and eventually the superconducting properties (jc, BC2, Birr). [ABSTRACT FROM AUTHOR]