Computational modeling of mixed oxidation-carburization processes: Part 1

Autor:	R. Petkovic-Luton, T. A. Ramanarayanan, S. Ling
Rok vydání:	1993
Předmět:	Austenite Materials science Diffusion Metallurgy Alloy technology industry and agriculture Metals and Alloys Oxide engineering.material equipment and supplies Chromia Corrosion Inorganic Chemistry chemistry.chemical_compound chemistry Materials Chemistry engineering Spallation Dissolution
Zdroj:	Oxidation of Metals. 40:179-196
ISSN:	1573-4889 0030-770X
DOI:	10.1007/bf00665264
Popis:	Heat-resistant alloys used in mixed-oxidant environments rely on the formation of a chromia, alumina, or silica surface film for corrosion resistance and the presence of second-phase precipitates in the matrix often for their strength properties. The growth of the oxide film on such alloys is often accompanied by the dissolution of precipitates in the alloy subsurface region. Continued oxidation combined with oxide-scale spallation tends to decrease the content of the oxide-forming constituent to such a level that protective scaling can no longer occur and severe degradation can develop. In the present work, the initial corrosion processes involving the complex coupling between oxide scale growth and precipitate dissolution is simulated computationally. As an example, a Ni-Cr alloy containing Cr 23 C 6 precipitates was exposed to an oxidizing-carburizing environment. An approach combining finite difference and Newton-Raphson methodologies is developed to model this diffusion/ dissolution process, incorporating the point-defect-chemistry aspects of the oxide scale. The model is able to predict the chemical and microstructural evolution of high-chromium austenitic alloys during the initial stages of oxidation-carburization.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::5b79fd1839eb2e126e9a9455b4e2ec28 https://doi.org/10.1007/bf00665264 Zobrazit plný text záznamu Full text from SpringerLink