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The cyclic oxidation behavior of Hf/Y-doped B2 FeAl intermetallics at 1373 K was investigated.For an undoped FeAl alloy,premature spallation of the alumina film occurs due to the formation of numerous voids at the film/alloy interface and apparent shrinkage in the film.In contrast to this,doping with either Hf or Y significantly improves the interfacial adhesion between the alumina film and the alloy substrate,particularly with Hf-doping.Microstructural observation in combination with Auger electron spectroscopic analysis suggests that in addition to prohibiting interfacial void formation and alleviating film shrinkage,the addition of Hf in the FeAl alloy could consolidate the film/alloy interface by directly participating in chemical bonding across the interface as a Hf ion.This causes the spallation of alumina film from the equiaxed grains/columnar grains interface rather than the bottom of the film.