Yosuke Nishimura , Anna Gubarevich , Katsumi Yoshida , Koji Okamoto
{"title":"Oxide growth and corrosion resistance of Si-containing SiC fuel matrices fabricated by reaction sintering for high-power nuclear reactors","authors":"Yosuke Nishimura , Anna Gubarevich , Katsumi Yoshida , Koji Okamoto","doi":"10.1016/j.oceram.2025.100740","DOIUrl":null,"url":null,"abstract":"<div><div>To assess the potential risk of fuel matrix degradation, this study examines the oxidation behavior of the reaction-sintered SiC containing residual Si (Si-RS-SiC) during air-ingress accidents. Si-RS-SiC samples were subjected to oxidation tests in air and under 1 ppm O<sub>2</sub> flow using thermogravimetric analysis (TGA). The morphology and thickness of the silicon oxide layer were investigated using scanning electron microscopy with energy-dispersive X-ray spectroscopy. The Si-RS-SiC exhibited exceptional resistance to air oxidation up to 1400°C, forming a uniform oxide layer of 20 μm thickness with a pure Si layer (2 μm thick) between SiO<sub>2</sub> and SiC at this temperature. At lower temperatures, the Si-RS-SiC formed oxide layers with irregular thickness, which became thicker and more uniform as the temperature increased. Additionally, TGA tests in 1 ppm O<sub>2</sub> showed that the passive/active transition behavior of Si-RS-SiC shifts in a preferable direction compared to previously reported Si-less RS-SiC, indicating that the presence of residual Si significantly enhances the corrosion resistance.</div></div>","PeriodicalId":34140,"journal":{"name":"Open Ceramics","volume":"21 ","pages":"Article 100740"},"PeriodicalIF":2.9000,"publicationDate":"2025-01-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Open Ceramics","FirstCategoryId":"1085","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S2666539525000070","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"MATERIALS SCIENCE, CERAMICS","Score":null,"Total":0}
引用次数: 0
Abstract
To assess the potential risk of fuel matrix degradation, this study examines the oxidation behavior of the reaction-sintered SiC containing residual Si (Si-RS-SiC) during air-ingress accidents. Si-RS-SiC samples were subjected to oxidation tests in air and under 1 ppm O2 flow using thermogravimetric analysis (TGA). The morphology and thickness of the silicon oxide layer were investigated using scanning electron microscopy with energy-dispersive X-ray spectroscopy. The Si-RS-SiC exhibited exceptional resistance to air oxidation up to 1400°C, forming a uniform oxide layer of 20 μm thickness with a pure Si layer (2 μm thick) between SiO2 and SiC at this temperature. At lower temperatures, the Si-RS-SiC formed oxide layers with irregular thickness, which became thicker and more uniform as the temperature increased. Additionally, TGA tests in 1 ppm O2 showed that the passive/active transition behavior of Si-RS-SiC shifts in a preferable direction compared to previously reported Si-less RS-SiC, indicating that the presence of residual Si significantly enhances the corrosion resistance.