Zviad Kovziridze

Show more
Georgian Technical University, Institute of Bionanoceramics and Nanocomposites Technology, Tbilisi, Georgia.
Show less

Abstract: Goal: Formulation of empiric formula, which establishes relations between major matrix parameters of ceramic materials and composites and the coefficient of resistance to material thermogradient. Method: Harcpurt’s method of cooling of water in boiling regime till disappearance of water. Results: It is proved that work-pieces reveal maximum thermal resistance and preservation of exploitation properties, when total closed porosity is within 2% - 8%, and pore sizes vary within 1 - 6 mcm. Besides, they are more or less of spherical form and are spread equally in the matrix. Conclusion: Thermogradient effect formula was defined for complex form work-pieces, when surfaces in the pieces are transacted several times by angles of various curvature radii.

Keywords: Thermogradient Effect, Matrix Curvature Radius, Parameters, Temperature Field, Thermal Stress, Thermal Expansion

Cite this paper: Kovziridze, Z. (2018) Formula of Thermogradient Effect. Journal of Electronics Cooling and Thermal Control, 8, 49-54. doi: 10.4236/jectc.2018.84004.

References

[1]   Grathwohl, G. (1993) Mechanische Eigenschaften Konnstruktionswerkstoffe. DGM Information sgesellschaft Verlag.

[2]   Munz, D. and Fett, T. (1989) Mechanische Verhalten keramischer Werkstoffe. Springer, Verlag, Berlin, Heidelberg, New York, London, Paris, Tokyo, Hong Kong.
https://doi.org/10.1007/978-3-642-51710-5

[3]   Maslennikova, G.N. and Kharitonov, F.Ya. (1977) Electro-Ceramic, Resistant to Thermal Shocks. Energy, Moscow.

[4]   Davidge, T.G. (1967) Thermal Shock and Fracture in Ceramics. Transactions of the British Ceramic Society, 66, 405-422.

[5]   Sobolev, I.D. and Egorov, V.I. (1962) Thermal Fatigue and Thermal Shock. In: Stability and Deformation in Inhomogeneous Temperature Fields. Gosatomizdat, Moscow, 194.

[6]   Natsenko, A.I. (1971) Thermal Stability of Brittle Materials. In: Theoretical and Technological Researches in the Sphere of Refractory Materials. Collections of Scientific Works of Ukrainian Scientific Researches, Institute of Refractory Materials. Issue: 15, “Metallurgy”, Moscow, 189-208.

[7]   Mikheev, M.A. and Mikheev, I.M. (1973) Principles of Heat Transfer. Energy, Moscow, 319.

[8]   Kingery, V.D. (1963) Measurements at High Temperatures. Metallurizdat, Moscow, 466.

[9]   Shvedkov, E.L., et al. (1991) Dictionary of New Ceramic. Naukova Dumka, Kiev, 116-117.

[10]   Hornbogen, E. (1992) Werkstoffe. Springer-Verbag, Berlin, Heidelberg, New York, London, Paris, Tokyo, Hong Kong, Barcelona, Budapest.

[11]   Hasselman, D.P.H. (1967) Approximate Theory of Thermal Stress Resistance of Brittle Ceramics Involving Creep. Journal of the American Ceramic Society, 50, 454.
https://doi.org/10.1111/j.1151-2916.1967.tb15160.x

[12]   Kharitonov, F.Ya. and Sherenova, O.A. (1969) Modern Methods of Evaluation of Thermal Stability of Ceramic Materials and Criteria of Its Determination. Heat Resistant Ceramic (Abstracts of Reports of Scientific-Technical Conference, Tiraspol). “Informemelectro”, Moscow, 3.

[13]   Loffler, W. and Petermann, K. (1968) Dichte weissbrennende Cordieritkeramik als Werkstoff fuer Flammenfestesgeschier. Silikattechnik, 19, 54.

[14]   Timoshchenko, S.P. (1946) Strength of Materials. Gostecjizdat, Moscow, 456.

[15]   Winkelmann, A. and Schott, O. (1894) Veberthermische Widerstandskoefficienten verschiedener Glaser in ihrer Abhangigkeit von der chemischen Zusammensetzung. Annalen der Physik und Chemie, 51, 730.

[16]   Pogodina-Alekseeva, G.I. (1959-60) Reference Book for Machine-Building Materials. Mashgiz, 450.

[17]   Bartenov, G.M. and Lioznyanskaya, S.G. (1953) Reference Book for Various Methods of Testing Glasses for Thermal Resistance. Collection of Works of All-Union Sci. Res. Institute of Glass, No. 32, 96-104.

[18]   Morozov, E.M. and Fridman, Ya.B. (1962) Thermal Tensions and Evaluation of Their Values. In: Strength and Deformation in Inhomogeneous Temperature Fields, Gosatomizdat, 30.

[19]   Timoshenko, S. and Goodier, I.N. (1951) Theory of Elasticity. McGraw Hill, New York, 250.

[20]   Baker, T.C. and Preston, F.W. (1946) Fatigue of Glass under Static Loads. Applied Physics, 17, 170.
https://doi.org/10.1063/1.1707702

[21]   Budworth, D.W. (1970) Theory of Pore Closure during Sintering. Transactions of the British Ceramic Society, 69, 29-31.

[22]   Helga Gollis-Szibov-zum Zusammensetzung der Gefuegedaten und mechanischen Eigenschaften von Porzellan. Dissertation zur Erlengung des Grades eines Doktor Ingenieur. 1979 April. Technische Universitaet Clausthal, s. 3-117.

[23]   Strelkov, K.K. (1972) Structure and Properties of Refracrory Material. Metallurgy, 216.

[24]   Kovziridze, Z., Hennicke, H.W. and Kharitonov, F. (1998) Thermomechanics of Ceramics Monograph. FH Karlsruhe BRD.

[25]   Kovziridze, Z. (1993) Elaboration of Scientific Principles and Technology of Obtaining Celsian and Alumino-Silicate Ceramic by the Use of Barite and Pearlite. Thesis for Gaining Scientific Degree of a Doctor of Technics, 104-110.

[26]   Formula of Thermogradient Effect (2017) Georgian National Intellectual Property Center “Georgia Patent” (Sakpatenti) Certificate of Deposition.