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Title: Microautoradiographic characterization of ROVER bore coating interfaces

Abstract

Declassified 28 Aug 1973. In an effort to understand the anomalous nonadherence of the NbC bore coatings on fueled ROVER elements, a modified microautoradiographic method was used to reveal the U distribution at the coating/ graphite interface. The method was used on elements manufactured with a reduced U content at the interface. Correlation between alpha tracks and the surrounding microstructure was excellent. Observations are consistent with the concept that uranium is responsible for an accelerated attack on the graphite during coating, although this is not explicitly proven. The presence of U in amounts below the detection limit of the method used is associated with tightly adherent NbC coatings. (auth)

Authors:
Publication Date:
Research Org.:
Battelle Pacific Northwest Labs., Richland, Wash. (USA)
OSTI Identifier:
4336359
Report Number(s):
BNWL-737
NSA Number:
NSA-29-027389
DOE Contract Number:
AT(45-1)-1830
Resource Type:
Technical Report
Resource Relation:
Other Information: Declassified 28 Aug 1973. Orig. Receipt Date: 30-JUN-74
Country of Publication:
United States
Language:
English
Subject:
N50330* -Metals, Ceramics, & Other Materials-Plastics & Other Materials-Properties, Structure & Phase Studies; N77800 -Reactors-Space, Mobile, Propulsion, Transportation & Package Reactors; *FUEL ELEMENTS- MATERIALS TESTING; *ROVER REACTORS- FUEL ELEMENTS; AUTORADIOGRAPHY; COATINGS; GRAPHITE; INTERFACES; NIOBIUM CARBIDES; OPENINGS; URANIUM; NESDPS Office of Nuclear Energy Space and Defense Power Systems

Citation Formats

Bunnell, L.R. Microautoradiographic characterization of ROVER bore coating interfaces. United States: N. p., 1968. Web. doi:10.2172/4336359.
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Bunnell, L.R. Microautoradiographic characterization of ROVER bore coating interfaces. United States. doi:10.2172/4336359.
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Bunnell, L.R. Thu . "Microautoradiographic characterization of ROVER bore coating interfaces". United States. doi:10.2172/4336359. https://www.osti.gov/servlets/purl/4336359.
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@article{osti_4336359,
title = {Microautoradiographic characterization of ROVER bore coating interfaces},
author = {Bunnell, L.R.},
abstractNote = {Declassified 28 Aug 1973. In an effort to understand the anomalous nonadherence of the NbC bore coatings on fueled ROVER elements, a modified microautoradiographic method was used to reveal the U distribution at the coating/ graphite interface. The method was used on elements manufactured with a reduced U content at the interface. Correlation between alpha tracks and the surrounding microstructure was excellent. Observations are consistent with the concept that uranium is responsible for an accelerated attack on the graphite during coating, although this is not explicitly proven. The presence of U in amounts below the detection limit of the method used is associated with tightly adherent NbC coatings. (auth)},
doi = {10.2172/4336359},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Thu Aug 01 00:00:00 EDT 1968},
month = {Thu Aug 01 00:00:00 EDT 1968}
}
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Technical Report:
View Technical Report (9.21 MB)
DOI:  10.2172/4336359
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