ISSN:
1573-4889
Keywords:
Oxidation behavior
;
ODS ferritic alloys
Source:
Springer Online Journal Archives 1860-2000
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Notes:
Abstract This investigation was undertaken in an attempt to gain a fundamentalunder-standing of the oxidation behavior of a fine-grain MA 956 in thetemperature range 800 to 1200°C, with emphasis placed on the scalemorphology and oxidation kinetics. Oxidation reaction led to the formationof a thin and dense alumina scale, irrespective of the oxidationtemperature. At intermediate temperatures plateletlike oxides of alumina,probably θ-Al2O3, covered the surface, whereas at othertemperatures small nodules of Fe-, Cr-, Ti or Y-rich oxides were observed inthe outer part of the alumina scale. The temperature dependence of theparabolic rate constant revealed a change in the oxidation mechanism with atransition at about 1000°C. The high-temperature mechanism is controlled bythe formation of α-alumina, whereas the low-temperature oxidationmechanism is controlled by formation of metastable alumina. Comparison withthe reported oxidation kinetics for coarse-grain MA 956 is inconclusive,since microstructure (grain size, texture) of the substrate changed duringoxidation in the high-temperature range.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1023/A:1004582713929
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