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 JECTC  Vol.8 No.3 , September 2018
Failure Stress Energy Formula
Abstract: Goal: In the process of exploitation of ceramic composites often we encounter not only high mechanical stresses but also thermal loads and air-thermal shocks. These loads are transformed into failure/rupture stress energy, when strength of work-pieces is less than loads, which develops pluck from the crack top, resulting in destruction of objects. Considering such extreme operation conditions computation of energies which contribute to materials catastrophe seems rather interesting. Method: The formula parameters were selected on the basis of study and generalization of micro- and macro-mechanical characteristics of ceramic materials. Results: The formula covers the process of creation of energies as a result of mechanical and thermal loads affecting the work-piece and analyses of mechanisms of impact of these energies on the cracks existing in the material; results of energies affecting the existing cracks as a result of such loads and results of starting of mechanisms of spreading of energies developed inside the work piece, which lead material to the catastrophe. Conclusion: On the basis of crack development mechanisms the universal relationship of total energy of the work-piece and its mass was established considering crack developing speed under critical stress conditions. Failure stress energy formula has been offered.
Cite this paper: Kovziridze, Z. (2018) Failure Stress Energy Formula. Journal of Electronics Cooling and Thermal Control, 8, 31-47. doi: 10.4236/jectc.2018.83003.
References

[1]   Lawn, B. (1999) Fracture of Brittle Solids. Cambridge University Press, Cambridge.

[2]   Kovziridze, Z., Hennicke, H.W. and Kharitonov, F. (1998) Thermomechanics of Ceramics. Fachhochschule Karlsruhe HochschulefuerTechnik, Karlsruhe.

[3]   Kovziridze, Z., Aneli, J., Nijaradze, N. and Tabatadze, G. (2017) Ceramic and Polymer Composites. LAP LAMBERT Academic Publishing. International BookMarket Service Ltd.

[4]   Kovziridze, Z., Nijaradze, N., Tabatadze, G. and Aneli, J. (2016) Ceramic and Polymer Composites. Monograph, Georgian Technical University, Tbilisi.

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

[6]   Grifith, A.A. (1920) The Phenomena of Rupture and Flow in Solids. Philosophical Transactions of the Royal Society A, 221, 163-198.

[7]   Shvedkov, E.L., Kovensky, I.I., Denisenko, E.T. and Zyrin, A.V. (1991) Dictionary Reference Book for New Ceramic. Academy of Sciences of Ukraine. Institute of Problems of Material Sciences, Kiev, “NaukovaDumka”, 115-116.

[8]   Richerson, D.W. (1992) Modern Ceramic Engineering. Marcel Dekker Inc., New York.

[9]   Grathwohl, G. and Kuntz, M. (2004) Mechanische Eigenschaftenim Buch Technische Keramik. Herausgeber W. Kollenberg, VULKAN_VERLAG ESSEN, Germany, 45-55.

[10]   Munz, D. and Fett, T. (1999) Ceramics: Mechanical Properties, Failure Behavior, Materials Selection. Springer-Verlag Berlin Heidelberg, New York, 61.
https://doi.org/10.1007/978-3-642-58407-7

[11]   Grathwohl, G. (1993) Mechanische Eigenschaftenkeramischer Konstruktionswerkstoffe DGM Informationsgesellschaft mbh.

[12]   Natsenko, A.I. (1971) Thermal Stability of Brittlematerials. Journal of Metallurgy, 15, 189-208.

[13]   Kingery, W.D. (1963) Measurements at High Temperatures. “Metallurgizdat”, Moscow, 466.

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

[15]   Troshchenko, V.T. (1971) Fatigue and Inelasticity of Metals. “NaukovaDumka”, Kiev, 268.

[16]   Pisarenko, G.S., Troshchenko, V.T., Timoshchenko, V.G., et al. (1962) Stability of Metal-Ceramic Materials and Alloys at Normal and High Temperatures. Kiev. Published by Academy of Sciences of Ukraine, SSR, 275.

[17]   Geitwud, B.E. (1959) Temperature Stresses. Moscow Edition, “Foreign Literature”, 349.

[18]   Kovziridze, Z., Nijaradze, N., Tabatadze, G., Cheishvili, T., Mestvitishvili, Z., Mshvildadze, M. and Darakhvelidze, N. (2017) Obtaining of Composites by Metal-Thermal and Nitriding Processes in Si-Sic-Al-Geopolymer System. Ceramic and Advanced Technologies, 19, 33-52.
http://www.ceramics.gtu.ge
https://doi.org/10.4236/jectc.2017.74009


[19]   Kovziridze, Z., Nijaradze, N., Tabatadze, G., Cheishvili, T., Mshvildadze, M., Mestvirishvili, Z., Kinkladze, V. and Daraxvelidze, N. (2007) Obtaining of SiAlON Composite via Metal-Thermal and Nitrogen Processes in the SiC-Si-Al-Geopolymer System. Journal of Electronics Cooling and Thermal Control, 7, 103-122.
http://www.scirp.org/journal/jectc

[20]   Maslennikova, G.N. and Kharitonov, F.Ya. (1977) Electro-Ceramic, Stable to Thermal Shocks. Moscow. Energy, 9-10.11-18, 163-175.

[21]   Kingery, W.D. (1955) Factors Affecting Thermal Shock Resistance of Ceramic Materials. Journal of the American Ceramic Society, 38, 3-15.
https://doi.org/10.1111/j.1151-2916.1955.tb14545.x

[22]   Buessem, W. (1955) Thermal Shock Testing. Journal of the American Ceramic Society, 38, 15-17.
https://doi.org/10.1111/j.1151-2916.1955.tb14546.x

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

[24]   Failure Stress Energy Formula. Georgian National Intellectual Property Center “Georgia Patent” (Sakpatenti). Certificate of Deposition 7289.2018.03.27.

 
 
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