The behaviour of sandwich structures of cold cathodes has been studied in a glow discharge. The differences in the behaviour of the cold-cathode composite structures under the action of a glow discharge in a helium-neon mixture are discussed.
The corrosion resistance of aluminothermic vanadium and vanadium-based binary (with 10 and 35 at. % Ti) and ternary (V–Ti–Cr) alloys in lithium is studied upon neutron irradiation. Samples of the alloys sealed in lithium-filled ampules are irradiated with fast neutrons to a fluence of 1023 cm–2 at 350–830°C in a BOR-60 reactor. It is found that the concentration of interstitial impurities (oxygen and carbon) at the surface of vanadium alloys upon irradiation is higher than that in the alloys studied under static conditions. When the vanadium alloys operate under irradiation and attack by lithium used as a heat-transfer medium, a high contamination of the surface layers in the alloys with interstitial impurities and their effect on the physical and mechanical properties of the alloys it should be taken into account.
The vacancy migration energy in fcc metals is calculated using a modified embeddedatom method and with allowance for the relaxation of the atoms nearest to a vacancy. The calculated energies are close to the experimentally determined vacancy migration energies. Taking into account the relaxation of the atoms nearest to a vacancy makes it possible to find a relation between the sublimation energy of a metal and the calculated vacancy migration energy. This relation is shown to correlate satisfactorily with the experimental relation between these parameters.
For modelling thermodynamic properties of the Fe–Cr alloys necessary to know the concentra tion dependences of the Debye temperature, the lattice parameter, the elastic moduli, the average magnetic moment, and the Curie temperature. The investigations are performed on iron alloys with chromium or vana dium in the concentration range 2–8 at %. The lattice parameters of the alloys are determined by comparing them with a standard sample placed on the surface of the sample under study. As the standard, a silicon crystal is used, and its lattice parameter is measured by the highprecision Bond method. The Debye temperatures of the alloys are determined from the temperature dependences of the integrated Xray diffraction line inten sities. The specific magnetization is measured by the Faraday method to compare the magnetic properties of Fe–Cr and Fe–V alloys. The partial magnetic moment of the iron atom is shown to increase with the alloy ingelement concentration.
The interaction of uranium mononitride UN with a refractory metal (rhenium) is studied in the temperature range 1773–2273 K. The coefficients of uranium diffusion from UN into polycrystalline and singlecrystal rhenium and their temperature dependences are determined. The diffusion mobility of uranium in rhenium is shown to be lower than that in molybdenum and to be higher than in tungsten.