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This article presents results of the study on the dependence of the structural-phase state of alloys based on Ti-12.52Al-43.08Nb system (wt.-%) on the temperature of spark plasma sintering. It has been established that spark plasma sintering of Ti-Al-Nb alloys under the temperature of 1500 °C resulted in melting the aluminum component of the mixture that, in turn, negatively affects the quality of ready products. It has also been shown that stepping up the sintering temperature from 1000 °C to 1300 °C leads to increasing volume fraction of O-phase up to 49.63 % due to rapid precipitation of O-phase from B2-phase and Ti3Al-phase. It has been revealed that intermetallic composites obtained under the temperature of 1300 °C are characterized by a dominant two-phase В2+О structure which is more suitable for strengthening sorption properties of hydrogen-storing materials based on Ti-Al-Nb.

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The paper considers a method of tungsten surface carbidization using a beam-plasma discharge (BPD), which was implemented in a plasma-beam installation (PBI). The advantage of this method is to create conditions for chemical reactions and physical processes as close as possible to those possible in thermonuclear installations. The BPD makes it possible to generate plasma using different working gases. Methane was used as a plasma-forming gas. The working gas pressure in a chamber was (1,3-1,4)·10-1 Pa. The temperature dependence of the carbidized layer formation on the tungsten surface under plasma irradiation was determined in the temperature range of 700-1700 °C. The formation of tungsten carbides in surface layers was confirmed by SEM and X-ray diffraction analysis. It was found that interaction between tungsten and methane in a wide temperature range can proceed with simultaneous or sequential formation of the carbide phases W2C and WC.

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