Fundamentals of the oxidation of high-temperature intermetallics

The existing knowledge of selective oxidation and the transition form internal to external oxidation are reviewed. The effects of transient oxidation on the transition and effects peculiar to oxidation of intermetallic compounds are emphasized. The effects of temperature on the transition to external oxidation and on the occurrence of pesting are considered. The influence of atmosphere composition on oxidation rates and morphologies and on the formation of volatile reaction products is described. Selected data for compounds of primary interest as high temperature materials (aluminides, silicides, beryllides etc.) are used to illustrate the above-mentioned fundamentals. Finally, the corrosion behavior of intermetallics in more complex environments such as those containing mixed-oxidants or molten salts are briefly discussed