Mechanical and thermomechanical behavior of refractories – from basic concepts to effective property calculations

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F60461373%3A22310%2F18%3A43916722" target="_blank" >RIV/60461373:22310/18:43916722 - isvavai.cz</a>

Výsledek na webu

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DOI - Digital Object Identifier

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Jazyk výsledku

angličtina

Název v původním jazyce

Mechanical and thermomechanical behavior of refractories – from basic concepts to effective property calculations

Popis výsledku v původním jazyce

Refractories are coarse-grained heterogeneous materials, usually multiphase ceramics, that can withstand high temperatures and are typically used for the construction of high-temperature components such as melter, kiln and furnace linings in the iron and steel industry, non-ferrous metal industry, glass and ceramic industry, cement industry, chemical industry, incineration of municipal waste or biomass and several other purposes (kiln furniture, gas burners etc.). Apart from their use in direct contact with the liquid melts and aggressive gases, where corrosion issues play a major role, refractories are often used as high-temperature insulation materials, where their main function consists in insulating the high-temperature equipment from its surroundings. For all these applications the mechanical and thermomechanical behavior of refractory materials is of vital importance and must be reliably known not only at room temperature but also at high temperature. Also their behavior during thermal cycling and thermal shock is a critical issue. This contribution explains the basic concepts on which a rational description of refractory materials should be based, i.e., the principles of modeling the elastic and anelastic behavior (including creep, viscoelastic and elastoplastic behavior, high-temperature strength and damping), as well as selected issues concerning the measurement of mechanical, thermophysical and thermomechanical properties in dependence of the temperature. It is shown how the effective elastic properties, specific heat, thermal conductivity and thermal expansion coefficient can be calculated for multiphase materials using micromechanical bounds (multiphase Wiener-Paul and Hashin-Shtrikman bounds) and model relations (effective medium approximations) or mixture rules and cross-property relations (where available). Also the model relations currently available for estimating the porosity dependence of effective properties are summarized, including cross-property relations. For the most important refractory phases critically evaluated property data are given for elastic constants, specific heat, thermal conductivity and thermal expansion coefficient, and the temperature dependence of these properties is discussed. This concerns refractory phases from the ternary system magnesia-alumina-silica and its binary partial systems, including the pure end members, as well as zirconia, silicon carbide, carbon (graphite) and fused silica (silica glass). The chapter may serve as a guide to the composition- and microstructure-based interpretation of experimental findings in refractory materials. Based on the concepts and refractory materials data given in this chapter, taking into account the general issues concerning strength measurements, the reader should be able to realistically assess even such complex quantities as thermal shock resistance parameters.

Název v anglickém jazyce

Mechanical and thermomechanical behavior of refractories – from basic concepts to effective property calculations

Popis výsledku anglicky

Refractories are coarse-grained heterogeneous materials, usually multiphase ceramics, that can withstand high temperatures and are typically used for the construction of high-temperature components such as melter, kiln and furnace linings in the iron and steel industry, non-ferrous metal industry, glass and ceramic industry, cement industry, chemical industry, incineration of municipal waste or biomass and several other purposes (kiln furniture, gas burners etc.). Apart from their use in direct contact with the liquid melts and aggressive gases, where corrosion issues play a major role, refractories are often used as high-temperature insulation materials, where their main function consists in insulating the high-temperature equipment from its surroundings. For all these applications the mechanical and thermomechanical behavior of refractory materials is of vital importance and must be reliably known not only at room temperature but also at high temperature. Also their behavior during thermal cycling and thermal shock is a critical issue. This contribution explains the basic concepts on which a rational description of refractory materials should be based, i.e., the principles of modeling the elastic and anelastic behavior (including creep, viscoelastic and elastoplastic behavior, high-temperature strength and damping), as well as selected issues concerning the measurement of mechanical, thermophysical and thermomechanical properties in dependence of the temperature. It is shown how the effective elastic properties, specific heat, thermal conductivity and thermal expansion coefficient can be calculated for multiphase materials using micromechanical bounds (multiphase Wiener-Paul and Hashin-Shtrikman bounds) and model relations (effective medium approximations) or mixture rules and cross-property relations (where available). Also the model relations currently available for estimating the porosity dependence of effective properties are summarized, including cross-property relations. For the most important refractory phases critically evaluated property data are given for elastic constants, specific heat, thermal conductivity and thermal expansion coefficient, and the temperature dependence of these properties is discussed. This concerns refractory phases from the ternary system magnesia-alumina-silica and its binary partial systems, including the pure end members, as well as zirconia, silicon carbide, carbon (graphite) and fused silica (silica glass). The chapter may serve as a guide to the composition- and microstructure-based interpretation of experimental findings in refractory materials. Based on the concepts and refractory materials data given in this chapter, taking into account the general issues concerning strength measurements, the reader should be able to realistically assess even such complex quantities as thermal shock resistance parameters.

Druh

C - Kapitola v odborné knize

CEP obor

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OECD FORD obor

20504 - Ceramics

Projekt

<a href="/cs/project/GA18-17899S" target="_blank" >GA18-17899S: Částečně a plně slinutá keramika - příprava, mikrostruktura, vlastnosti, modelování a teorie slinování</a><br>

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2018

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název knihy nebo sborníku

Refractory Materials – Characteristics, Properties and Uses

ISBN

978-1-5361-3862-7

Počet stran výsledku

100

Strana od-do

33-132

Počet stran knihy

238

Název nakladatele

Nova Science Publishers, Inc.

Místo vydání

New York

Kód UT WoS kapitoly

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