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Solute transport and the prediction of breakaway oxidation in gamma + beta Ni-Cr-Al alloysThe Al transport and the condition leading to breakaway oxidation during the cyclic oxidation of gamma + beta NiCrAl alloys have been studied. The Al concentration/distance profiles were measured after various cyclic oxidation exposures at 1200 C. It was observed that cyclic oxidation results in a decreasing Al concentration at the oxide/metal interface, maintaining a constant flux of Al to the Al2O3 scale. It was also observed that breakaway oxidation occurs when the Al concentration at the oxide/metal interface approaches zero. A numerical model was developed to simulate the diffusional transport of Al and to predict breakaway oxidation in gamma + beta NiCrAl alloys undergoing cyclic oxidation. In a comparison of two alloys with similar oxide spalling characteristics, the numerical model was shown to predict correctly the onset of breakaway oxidation in the higher Al-content alloy.
Document ID
19840059871
Document Type
Conference Paper
Authors
Nesbitt, J. A. (Michigan Technological Univ. Houghton, MI, United States)
Heckel, R. W. (Michigan Technological University Houghton, MI, United States)
Date Acquired
August 12, 2013
Publication Date
January 1, 1984
Subject Category
METALLIC MATERIALS
Funding Number(s)
CONTRACT_GRANT: NSG-3215
Distribution Limits
Public
Copyright
Other