ISSN:
1573-4889
Keywords:
oxidation
;
multilayer oxides
;
oxidation kinetics theory
;
diffusion mechanisms
;
iron
Source:
Springer Online Journal Archives 1860-2000
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Notes:
Abstract A quantitative theory for the growth of three-layered oxide scales on pure metals that form MevO, MeδO, and MeɛO has been developed. The theoretical parabolic rate constants,K p (MevO),K p (MeδO), andK p (MeɛO), for the simultaneous growth of each oxide on metals are related to oxidation data of the overall rate constant,K p , and the oxide thickness ratios. These theoretical parabolic rate constants can also be calculated from diffusion data in each oxide, and the oxide thickness ratios can therefore be predicted. To verify the validity of the theory, it was applied to the oxidation of iron in air at temperatures of 800 to 1200° C. Good agreement was found between the theoretical parabolic rate constants calculated from oxidation data and from diffusion data for wustite and magnetite. However, to match with the rate constant calculated from oxidation data, additional information about short-circuit diffusion in hematite is required.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00659339
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