Oxidation behaviour of FeAl intermetallics: effects of reactive elements on cyclic oxidation properties

The cyclic oxidation behaviour of doped and undoped FeAl intermetallics was studied at 1000-1200 degreesC, It was found that the scale spallation resi stance of FeAl was remarkably improved by reactive element (Zr and/or Y) ad ditions. The exposure time in each cycle also affected the scale spallation tendency of undoped FeAl, Cycling with short exposure times changed the sc ale spallation mechanisms and improved the spallation resistance. Electron microscopy, microanalysis, and X-ray diffractometry were used to study the scale spallation processes. The effects of reactive element additions on sc ale spallation mechanisms are also discussed based on experimental observat ions and stress calculations.