Title: Steam oxidation of chromium corrosion barrier coatings for sic-based accident tolerant fuel cladding

Abstract

SiC-based materials are currently being considered for accident tolerant fuel (ATF) cladding, however, there are concerns regarding hydrothermal corrosion rates and hermeticity. These issues may be addressed with the utilization of a Cr corrosion barrier coating (CBC) but the interaction of Cr with SiC under loss of coolant accident (LOCA) conditions needs to be investigated. In the present work, Cr coatings were deposited onto chemically vapor deposited (CVD) SiC with either high power impulse magnetron sputtering (HiPIMS), cathodic arc (CA), or a combination of both. Annealing and steam thermogravimetric analysis (TGA) was used to study reaction product formation with and without oxidation. Additionally, after 1200 °C annealing, formation of a Cr_xC_y carbide layer at the ambient interface and a Cr_xSi_yC_z silicide layer at the SiC interface was observed. After 1200 °C TGA exposure, similar carbide and silicide layers were observed but with a Cr₂O₃ outer reaction layer and a Si and O rich interfacial layer forming between the carbide and silicide layers. Initial mass gain of the coatings during the 1200 °C TGA exposure was parabolic and were similar to reported rates of chromia formation. Mass gain behavior and observed transitions in chromia microstructure indicate that metallic Cr may bemore » consumed within the first ~1 h at 1200 °C and that subsequent chromia formation occurs at the expense of the underlying Cr carbide layer. Overall, the results show no detrimental impact of Cr coatings on the steam oxidation resistance of SiC up to 4 h at 1200 °C.« less

Authors:

Kane, K. A.  ^[1];

• Search DOE PAGES for author "Kane, K. A."
• Search DOE PAGES for ORCID "0000-0003-3647-3419"

Stack, P. I.M.  ^[2];

• Search DOE PAGES for author "Stack, P. I.M."
• Search DOE PAGES for ORCID "0000-0003-4450-4318"

Mouche, P. A.  ^[1];

• Search DOE PAGES for author "Mouche, P. A."
• Search DOE PAGES for ORCID "0000-0003-4793-5754"

Pillai, R. R.  ^[1];

• Search DOE PAGES for author "Pillai, R. R."
• Search DOE PAGES for ORCID "0000-0002-4368-8197"

Pint, B. A.  ^[1]

• Search DOE PAGES for author "Pint, B. A."
• Search DOE PAGES for ORCID "0000-0002-9165-3335"

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+ Show Author Affiliations

1. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
2. Univ. of Akron, OH (United States)

Publication Date:

Sat Oct 09 00:00:00 EDT 2021

Research Org.:

Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

Sponsoring Org.:

USDOE

OSTI Identifier:

1708844

Alternate Identifier(s):

OSTI ID: 1810959

Grant/Contract Number:  

AC05-00OR22725

Resource Type:

Accepted Manuscript

Journal Name:

Journal of Nuclear Materials

Additional Journal Information:

Journal Volume: 543; Journal Issue: 1; Journal ID: ISSN 0022-3115

Publisher:

Elsevier

Country of Publication:

United States

Language:

English

Subject:

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE WASTES FROM NUCLEAR FACILITIES; Accident tolerant fuel; Cladding; SiC; Steam oxidation; LOCA