Effect of long-term high-temperature exposure in a controlled atmosphere on mullite-corundum ceramics for advanced applications in nuclear power technology

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F60461373%3A22310%2F24%3A43929694" target="_blank" >RIV/60461373:22310/24:43929694 - isvavai.cz</a>

Nalezeny alternativní kódy

RIV/60461373:22320/24:43929694

Výsledek na webu

<a href="https://www.sciencedirect.com/science/article/pii/S0272884224015426?via%3Dihub" target="_blank" >https://www.sciencedirect.com/science/article/pii/S0272884224015426?via%3Dihub</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.ceramint.2024.04.157" target="_blank" >10.1016/j.ceramint.2024.04.157</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Effect of long-term high-temperature exposure in a controlled atmosphere on mullite-corundum ceramics for advanced applications in nuclear power technology

Popis výsledku v původním jazyce

This work investigates the behavior and properties of corundum and mullite ceramics at high temperatures and during very long exposures in a controlled atmosphere. The motivation of the work lies primarily in advanced applications in nuclear energy technology, specifically in the search for materials for helium-cooled reactors of the 4th generation. The studied ceramic samples Al63, Al70, Al76, Al96, Al100, where the number indicates the mass percentage of Al2O3, were exposed for 1000 h at a temperature of 900 degrees C in gaseous atmospheres of helium, nitrogen and air. The properties of the exposed and unexposed samples were evaluated by measuring the bending strength at room temperature (CMOR), hot modulus of rupture at high temperature (HMOR), and isothermal creep, BET method, and using electron microscopy. The color changes induced by the reducing atmosphere and temperature were also interpreted using a simple thermochemical model. The CMOR measurement results show that all ceramic samples do not significantly change their properties due to long-term exposure. The detected deviations in the exposed samples from the unexposed ones can be considered random caused by the inherent heterogeneous structure. A similar conclusion also applies in the case of the HMOR measurement results, except for the results for the Al63 sample, where the drop in the strength of the exposed samples by approx. 37 MPa (20 %) may be related with the highest proportion of polyvalent oxide admixtures of all studied ceramics, i.e. 1.01 wt % Fe2O3 and 0.52 wt % TiO2. The change in color indicates that the iron and titanium present are being reduced. However, none of the conducted experiments indicate that changes in the redox state associated with the formation of oxygen vacancies would significantly reduce strength at high temperatures or increase creep in mullite ceramics.

Název v anglickém jazyce

Effect of long-term high-temperature exposure in a controlled atmosphere on mullite-corundum ceramics for advanced applications in nuclear power technology

Popis výsledku anglicky

This work investigates the behavior and properties of corundum and mullite ceramics at high temperatures and during very long exposures in a controlled atmosphere. The motivation of the work lies primarily in advanced applications in nuclear energy technology, specifically in the search for materials for helium-cooled reactors of the 4th generation. The studied ceramic samples Al63, Al70, Al76, Al96, Al100, where the number indicates the mass percentage of Al2O3, were exposed for 1000 h at a temperature of 900 degrees C in gaseous atmospheres of helium, nitrogen and air. The properties of the exposed and unexposed samples were evaluated by measuring the bending strength at room temperature (CMOR), hot modulus of rupture at high temperature (HMOR), and isothermal creep, BET method, and using electron microscopy. The color changes induced by the reducing atmosphere and temperature were also interpreted using a simple thermochemical model. The CMOR measurement results show that all ceramic samples do not significantly change their properties due to long-term exposure. The detected deviations in the exposed samples from the unexposed ones can be considered random caused by the inherent heterogeneous structure. A similar conclusion also applies in the case of the HMOR measurement results, except for the results for the Al63 sample, where the drop in the strength of the exposed samples by approx. 37 MPa (20 %) may be related with the highest proportion of polyvalent oxide admixtures of all studied ceramics, i.e. 1.01 wt % Fe2O3 and 0.52 wt % TiO2. The change in color indicates that the iron and titanium present are being reduced. However, none of the conducted experiments indicate that changes in the redox state associated with the formation of oxygen vacancies would significantly reduce strength at high temperatures or increase creep in mullite ceramics.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

20504 - Ceramics

Projekt

<a href="/cs/project/TK02030024" target="_blank" >TK02030024: Stabilita a odolnost materiálů okruhů s vysokoteplotním héliem</a><br>

Návaznosti

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

Rok uplatnění

2024

Kód důvěrnosti údajů

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

Název periodika

Ceramics International

ISSN

0272-8842

e-ISSN

1873-3956

Svazek periodika

50

Číslo periodika v rámci svazku

13

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

8

Strana od-do

24273-24280

Kód UT WoS článku

001243534500001

EID výsledku v databázi Scopus

2-s2.0-85191316079