The present work is devoted to the search for new electrode materials for lowtemperature thermionic energy converters (TECs). As shown, the carbon nanostructures (СNS) adding to pure powdered titanium in an amount of 3-9% wt. and their subsequent mechanical mixing leads to the formation of composites that acquire new qualities that were not present in any of their original pure constituents. Thus, the significant changes in the mechanical and electrical characteristics of composites are observed. For example, the electrical conductivity is changed up to 2 orders in initial state of composites as well as its maximum values after samples' compaction are increased (1.6-5 times) in comparison with both the pure Ti powder and the pure thermally extended graphite (TEG) in corresponding compression states. Such changes are caused by the presence of contacts between the metal particles and the CNS in the metal-nanocarbon composites and, accordingly, the possibility of the transition of free charges, including hot charges, from the metal to the CNS.

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A study is made of the anisotropy of the properties of tungsten single crystals for equivalent crystallographic orientations relative to the growth axis. An essential difference in the interplanar spacings for samples with equivalent faces perpendicular and parallel to the growth axis was found. For the compared equivalent planes differences in the positron annihilation parameters were observed which point to an anisotropy of the Fermi surface caused by carbon atoms with an anisotropic electron configuration. The sublimation energy for equivalent faces is also shown to be anisotropic.