ISSN:
1573-4889
Keywords:
reactive-element effect
;
cyclic oxidation
;
oxidation kinetics
;
scale adhesion
;
cerium oxide
;
segregation
Source:
Springer Online Journal Archives 1860-2000
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Notes:
Abstract The reactive-element effect on high-temperature oxidation of chromium metal was studied at oxygen pressures of 105 Pa (1 atm) and 0.67 Pa and at temperatures of 800 and 1050°C under both isothermal and cyclic conditions. The reactive element, cerium, was applied as a cerium-oxide coating by sol-gel deposition. Growth and adherence of the chromia scale on the metallic substrate were investigated by kinetic weight-gain measurements, and the microstructure was characterized by scanning electron microscopy, transmission electron microscopy, EDX-analysis, X-ray diffraction, and Auger analysis. The study of the oxidation kinetics under isothermal conditions at 800°C clearly showed a reduction in the growth rate of the oxide film when cerium oxide was present. Improvement of the oxide-scale adhesion was also observed when ceria-coated chromium was subjected to thermal cycling. The applicability of a number of models which have been used to explain the reactive-element effect is discussed.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF01061925
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