Microstructure, elastic properties and high-temperature behavior of silica refractories

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F60461373%3A22310%2F16%3A43902682" target="_blank" >RIV/60461373:22310/16:43902682 - isvavai.cz</a>

Nalezeny alternativní kódy

RIV/67985891:_____/16:00471704

Výsledek na webu

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DOI - Digital Object Identifier

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Jazyk výsledku

angličtina

Název v původním jazyce

Microstructure, elastic properties and high-temperature behavior of silica refractories

Popis výsledku v původním jazyce

The microstructure, elastic properties and high-Temperature behavior of silica refractories are characterized by the Archimedes method, stereology-based image analysis, mercury porosimetry, dilatometiy and impulse excitation. Stereology-based image analysis and mercury porosimetry showed that the sample with lowest porosity (13.2 %) has the largest average cristobalite grain size (407 +- 44 ?m) and pore size (mode 17 ?m), whereas the samples with higher porosity (16.0-17.1 %) have smaller grain size (from 293 +- 43 to 298 +- 38 ?m) and pore size (mode 6 ?m). Moreover a small-size pore fraction (around 0.4 pm) is identified and attributed to microcracks. Room temperature elastic constants have been determined via impulse excitation from the resonant frequencies of flexural and anti-flexural vibrations of plate-shaped samples (Young's modulus 8.0-10.3 GPa, shear modulus 3.7-4.9 GPa, bulk modulus 3.1-3.8 GPa, Poisson ratio 0.053-0.086). Even after taking into account porosity via our exponential relation, the measured Young's moduli are smaller than the predicted ones by a factor of 4-5. This discrepancy is attributed to the presence of microcracks. The temperature dependence of the Young's modulus up to 1200 oC, measured by high-temperature impulse excitation from the flexural vibrations of bar-shaped samples, exhibits anomalies affected by the microstructure and related to the phase transitions between the low-And high-Temperature subpolymorphs of cristobalite and tridymite. These anomalies are closely related to the corresponding dilatational behavior.

Název v anglickém jazyce

Microstructure, elastic properties and high-temperature behavior of silica refractories

Popis výsledku anglicky

The microstructure, elastic properties and high-Temperature behavior of silica refractories are characterized by the Archimedes method, stereology-based image analysis, mercury porosimetry, dilatometiy and impulse excitation. Stereology-based image analysis and mercury porosimetry showed that the sample with lowest porosity (13.2 %) has the largest average cristobalite grain size (407 +- 44 ?m) and pore size (mode 17 ?m), whereas the samples with higher porosity (16.0-17.1 %) have smaller grain size (from 293 +- 43 to 298 +- 38 ?m) and pore size (mode 6 ?m). Moreover a small-size pore fraction (around 0.4 pm) is identified and attributed to microcracks. Room temperature elastic constants have been determined via impulse excitation from the resonant frequencies of flexural and anti-flexural vibrations of plate-shaped samples (Young's modulus 8.0-10.3 GPa, shear modulus 3.7-4.9 GPa, bulk modulus 3.1-3.8 GPa, Poisson ratio 0.053-0.086). Even after taking into account porosity via our exponential relation, the measured Young's moduli are smaller than the predicted ones by a factor of 4-5. This discrepancy is attributed to the presence of microcracks. The temperature dependence of the Young's modulus up to 1200 oC, measured by high-temperature impulse excitation from the flexural vibrations of bar-shaped samples, exhibits anomalies affected by the microstructure and related to the phase transitions between the low-And high-Temperature subpolymorphs of cristobalite and tridymite. These anomalies are closely related to the corresponding dilatational behavior.

Druh

D - Stať ve sborníku

CEP obor

JH - Keramika, žáruvzdorné materiály a skla

OECD FORD obor

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Projekt

<a href="/cs/project/GA15-18513S" target="_blank" >GA15-18513S: Příprava a charakterizace oxidové a silikátové keramiky s řízenou mikrostrukturou a modelování souvislostí mezi mikrostrukturou a vlastnostmi</a><br>

Návaznosti

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

Rok uplatnění

2016

Kód důvěrnosti údajů

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

Název statě ve sborníku

11th International Symposium on Ceramic Materials and Components for Energy and Environmental Applications

ISBN

978-1-119-23458-6

ISSN

1042-1122

e-ISSN

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Počet stran výsledku

12

Strana od-do

113-124

Název nakladatele

American Ceramic Society (ACerS)

Místo vydání

Westerville, Ohio

Místo konání akce

Vancouver / Canada

Datum konání akce

14. 6. 2015

Typ akce podle státní příslušnosti

WRD - Celosvětová akce

Kód UT WoS článku

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