Abstract
The fundamental oxidation characteristics of two U-base alloys, U-16.6 at.% Nb-5.6 at.% Zr and U-21at.% Nb, in the temperature range 500–1000° C in oxygen at 0.05 Torr are described. Both alloys undergo large dimensional changes during oxidation at temperatures above 650° C due to stresses generated in the oxide during oxidation. Oxidation rate curves for both alloys were determined at 100° C intervals between 500 and 1000° C; the activation energy for the process is shown to be small. The morphology of the oxide scale formed on the two alloys is complex and is described in detail. Stresses estimated at 106 psi are shown to develop in oxidizing specimens, and a mechanism for the generation of these stresses is proposed.
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J. V. Cathcart and G. F. Petersen, to be published.
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Research sponsored by the U.S. Atomic Energy Commission under contract with the Union Carbide Corporation.
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Cathcart, J.V., Pawel, R.E. & Petersen, G.F. The oxidation properties of U-16.6 at.% Nb-5.6 at.% Zr and U-21 at.% Nb. Oxid Met 3, 497–521 (1971). https://doi.org/10.1007/BF00604997
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DOI: https://doi.org/10.1007/BF00604997