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DOE OSTI · 1155053

Material selection for accident tolerant fuel cladding

Pint, B. A.·Terrani, K. A.·Yamamoto, Y.·Snead, L. L.
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Abstract

Alternative cladding materials are being investigated for accident tolerance, which can be defined as >100X improvement (compared to current Zr-based alloys) in oxidation resistance in steam environments at ≥1200°C for short (≤4 h) times. After reviewing a wide range of candidates, current steam oxidation testing is being conducted on Mo, MAX phases and FeCrAl alloys. Recently reported low mass losses for Mo in steam at 800°C could not be reproduced. Both FeCrAl and MAX phase Ti 2 AlC form a protective alumina scale in steam. Therefore, commercial Ti 2 AlC that is not single phase, formed a much thicker oxide at 1200°C in steam and significant TiO 2 , and therefore may be challenging to use as a cladding or a coating. Alloy development for FeCrAl is seeking to maintain its steam oxidation resistance to 1475°C, while reducing its Cr content to minimize susceptibility to irradiation assisted Cr-rich α’ formation. The composition effects and critical limits to retaining protective scale formation at >1400°C are still being evaluated.

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11 NUCLEAR FUEL CYCLE AND FUEL MATERIALSAl2O3FeCrAlLOCAMAX phaseMoTi2AlCaccident tolerant LWR Fuel claddinghigh temperature steam oxidation resistance

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Pint, B. A., Terrani, K. A., Yamamoto, Y., Snead, L. L.. 2015-09-14. Material selection for accident tolerant fuel cladding. https://doi.org/10.1007/s40553-015-0056-7

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