RESEARCH OF HIGH-TEMPERATURE CORROSION OF SiC-COATING ON GRAPHITE

The relevance of this work is caused by possible prospect of creating a Kazakhstani high-temperature gas-cooled reactor, in which a number of new materials science solutions will be applied regarding the graphite matrix and fuel cells. Silicon carbide (SiC) coatings will be used on reactor fuel cell...

Full description

Bibliographic Details
Main Authors: Saulet K. Askerbekov, Evgeniy V. Chikhray, Yuriy V. Ponkratov, Nikolay N. Nikitenkov
Format: Article
Language:Russian
Published: Tomsk Polytechnic University 2019-06-01
Series:Известия Томского политехнического университета: Инжиниринг георесурсов
Subjects:
Online Access:http://izvestiya.tpu.ru/archive/article/view/2131/1977
_version_ 1818017504016990208
author Saulet K. Askerbekov
Evgeniy V. Chikhray
Yuriy V. Ponkratov
Nikolay N. Nikitenkov
author_facet Saulet K. Askerbekov
Evgeniy V. Chikhray
Yuriy V. Ponkratov
Nikolay N. Nikitenkov
author_sort Saulet K. Askerbekov
collection DOAJ
description The relevance of this work is caused by possible prospect of creating a Kazakhstani high-temperature gas-cooled reactor, in which a number of new materials science solutions will be applied regarding the graphite matrix and fuel cells. Silicon carbide (SiC) coatings will be used on reactor fuel cells, in which graphite is the main constituent material. The aim of the research is to evaluate the corrosion rate of reactor graphite with SiC-coating in the temperature range from 750 to 1400 °C at the initial pressure of water vapor in the chamber 100 Pa. Object: isotropic fine-grained graphite of IG-110 brand with a protective SiC-coating thickness of 200 microns. Methods: programmable thermal desorption of samples in the presence of water vapor, mass spectrometric recording of the gas composition in the working chamber, microstructural studies, Raman spectroscopy, energy-dispersed X-ray spectroscopy. Results. It is shown that at pressures of water vapor of 100 Pa, the SiC-coating interacts with steam through a passive (forming an additional protective layer of amorphous silicon dioxide) mechanism. Corrosion of SiC in water vapor at temperatures of 1100–1400 °C occurs by orders of magnitude more intense than at 750–900 °C. A model for analytical description of the experimental results was developed and the parameters of the rate constant for water vapor interaction with a SiC-coating were calculated for sample temperatures of 1400, 1300, 1200, 1100, and 1000 °C. Microstructural studies of the samples before and after corrosion tests were carried out, which showed that a protective SiO2 film is formed on the surface with a SiC carbide coating during passive corrosion. The research results allow us to conclude that the prototype of a fuel with a SiC-coating has improved anti-corrosion properties and can be successfully used to reduce carbon chemical activity in fuel cells and fuel assemblies of high-temperature gas-cooled reactor without deteriorating their mechanical and temperature properties.
first_indexed 2024-04-14T07:27:57Z
format Article
id doaj.art-1511da29f23f4db29d2cbb51ffe5a910
institution Directory Open Access Journal
issn 2500-1019
2413-1830
language Russian
last_indexed 2024-04-14T07:27:57Z
publishDate 2019-06-01
publisher Tomsk Polytechnic University
record_format Article
series Известия Томского политехнического университета: Инжиниринг георесурсов
spelling doaj.art-1511da29f23f4db29d2cbb51ffe5a9102022-12-22T02:05:57ZrusTomsk Polytechnic UniversityИзвестия Томского политехнического университета: Инжиниринг георесурсов2500-10192413-18302019-06-0133069810810.18799/24131830/2019/6/2131RESEARCH OF HIGH-TEMPERATURE CORROSION OF SiC-COATING ON GRAPHITESaulet K. Askerbekov0Evgeniy V. Chikhray1Yuriy V. Ponkratov2Nikolay N. Nikitenkov3Kazakh National University named after Al-FarabiKazakh National University named after Al-FarabiNational Nuclear Center of the Republic of KazakhstanNational Research Tomsk Polytechnic UniversityThe relevance of this work is caused by possible prospect of creating a Kazakhstani high-temperature gas-cooled reactor, in which a number of new materials science solutions will be applied regarding the graphite matrix and fuel cells. Silicon carbide (SiC) coatings will be used on reactor fuel cells, in which graphite is the main constituent material. The aim of the research is to evaluate the corrosion rate of reactor graphite with SiC-coating in the temperature range from 750 to 1400 °C at the initial pressure of water vapor in the chamber 100 Pa. Object: isotropic fine-grained graphite of IG-110 brand with a protective SiC-coating thickness of 200 microns. Methods: programmable thermal desorption of samples in the presence of water vapor, mass spectrometric recording of the gas composition in the working chamber, microstructural studies, Raman spectroscopy, energy-dispersed X-ray spectroscopy. Results. It is shown that at pressures of water vapor of 100 Pa, the SiC-coating interacts with steam through a passive (forming an additional protective layer of amorphous silicon dioxide) mechanism. Corrosion of SiC in water vapor at temperatures of 1100–1400 °C occurs by orders of magnitude more intense than at 750–900 °C. A model for analytical description of the experimental results was developed and the parameters of the rate constant for water vapor interaction with a SiC-coating were calculated for sample temperatures of 1400, 1300, 1200, 1100, and 1000 °C. Microstructural studies of the samples before and after corrosion tests were carried out, which showed that a protective SiO2 film is formed on the surface with a SiC carbide coating during passive corrosion. The research results allow us to conclude that the prototype of a fuel with a SiC-coating has improved anti-corrosion properties and can be successfully used to reduce carbon chemical activity in fuel cells and fuel assemblies of high-temperature gas-cooled reactor without deteriorating their mechanical and temperature properties.http://izvestiya.tpu.ru/archive/article/view/2131/1977reactor graphitesic-coatinghtgrcorrosionwater vapor
spellingShingle Saulet K. Askerbekov
Evgeniy V. Chikhray
Yuriy V. Ponkratov
Nikolay N. Nikitenkov
RESEARCH OF HIGH-TEMPERATURE CORROSION OF SiC-COATING ON GRAPHITE
Известия Томского политехнического университета: Инжиниринг георесурсов
reactor graphite
sic-coating
htgr
corrosion
water vapor
title RESEARCH OF HIGH-TEMPERATURE CORROSION OF SiC-COATING ON GRAPHITE
title_full RESEARCH OF HIGH-TEMPERATURE CORROSION OF SiC-COATING ON GRAPHITE
title_fullStr RESEARCH OF HIGH-TEMPERATURE CORROSION OF SiC-COATING ON GRAPHITE
title_full_unstemmed RESEARCH OF HIGH-TEMPERATURE CORROSION OF SiC-COATING ON GRAPHITE
title_short RESEARCH OF HIGH-TEMPERATURE CORROSION OF SiC-COATING ON GRAPHITE
title_sort research of high temperature corrosion of sic coating on graphite
topic reactor graphite
sic-coating
htgr
corrosion
water vapor
url http://izvestiya.tpu.ru/archive/article/view/2131/1977
work_keys_str_mv AT sauletkaskerbekov researchofhightemperaturecorrosionofsiccoatingongraphite
AT evgeniyvchikhray researchofhightemperaturecorrosionofsiccoatingongraphite
AT yuriyvponkratov researchofhightemperaturecorrosionofsiccoatingongraphite
AT nikolaynnikitenkov researchofhightemperaturecorrosionofsiccoatingongraphite