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991.
We study some specific features of phase formation and gas saturation in the course of chemical and thermal treatment of VT1-0, OT4, and VT14 titanium alloys in carbon-nitrogen-containing (graphite and nitrogen under atmospheric pressure) and nitrogen-containing (molecular nitrogen under atmospheric pressure) media. Saturation was carried out at 750–1100°C, and the time of isothermal holding was 5 or 20 h. We have shown that, irrespective of the composition of the saturating medium, within the range 750–1000°C, the phase composition of coatings is identical and consists of TiN and Ti2N nitrides. The quantitative proportions between them depend on the temperature and time of treatment. Owing to the specific features of the composition of a carbon-nitrogen-containing medium, the depth of the diffusion sublayer increases, and the stoichiometry of cubic nitride decreases, which leads to an increase in the surface microhardness of nitride coatings. Carbonitride coatings are formed only at high saturation temperature (1100°C). Their maximum hardness is 2.5 GPa higher than that of nitrides formed under similar conditions.Translated from Fizyko-Khimichna Mekhanika Materialiv, Vol. 40, No. 3, pp. 81–87, May–June, 2004. 相似文献
992.
I. Hole T. Tybell J. K. Grepstad I. Wrnhus T. Grande K. Wiik 《Solid-state electronics》2003,47(12):2279
Heteroepitaxial LaFeO3(1 1 0) thin films with a thickness of 150 nm were grown on LaAlO3(0 0 1) by reactive sputtering in an inverted cylindrical magnetron geometry. Equilibrium conductivity was measured as a function of partial pressure of oxygen at T=1000 °C, and logσ plotted vs. logP(O2) showed a minimum in conductivity for P(O2)=10−11 atm and a linear response between 10−10 and 1 atm. This linear response makes thin films of LaFeO3 a promising material for oxygen sensor applications. We have also measured the time response of the film conductivity upon an abrupt change in the partial pressure of ambient oxygen from 10−2 to 10−3 atm, which was determined at 60 s for T=700 °C and <3.5 s at T=1000 °C. 相似文献
993.
S. B. Kashevskii I. V. Prokhorov 《Journal of Engineering Physics and Thermophysics》2004,77(4):727-730
A magnetooptical method of measurement of viscosity, which is based on recording the optical response (induced by the magnetic-field pulses) of a two-layer system resulting from the sedimentation of ferroparticles dispersed in the liquid under study, has been proposed. The procedure has been described and the results of measurement of the rheokinetics of a number of media, including polymer compositions formed into a thin film, in heating, evaporation, and polymerization have been presented. 相似文献
994.
A. I. Zav'yalov 《Chemical and Petroleum Engineering》1992,28(3):189-189
Translated from Khimicheskoe i Neftyanoe Mashinostroenie, No. 3, p. 25, March, 1992. 相似文献
995.
996.
N. I. Koronkevich D. A. Eliseev S. V. Yasinskii 《Power Technology and Engineering (formerly Hydrotechnical Construction)》1994,28(8):411-415
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 8, pp. 1–5, August, 1994. 相似文献
997.
998.
M. M. Selyametov O. B. Shevchenko I. É. Vitebskaya E. N. Kosheleva V. M. Danyutin 《Power Technology and Engineering (formerly Hydrotechnical Construction)》1992,26(3):137-140
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 3, pp. 6–8, March, 1992. 相似文献
999.
1000.
V. I. Slavov V. N. Zadorozhnaya V. I. Semerikov S. N. Kostylev 《Glass and Ceramics》1992,49(10):478-479
Translated from Steklo i Keramika, No. 10, p. 20, October, 1992. 相似文献