Abstract: The oxidation Kinetics of microcrystalline Fe₃Al was compared with that of normal grain Fe₃Al at 1000℃ in air. It was shown that the oxidation rate of microcrystalline Fe₃Al was heavily decreased. The oxidation kinetics of microcrystalline Fe₃Al failed to obey the parabolic law. It was suggested that the oxide scale turned into microcrystalline state since the nuclear probability of oxide was extremely increased. The short circuit diffusion through oxide scale was dominant. An expression, x⁴=kpt, has been derived for the oxidation kinetics of microcrystalline Fe₃Al based upon the model of short circuit diffusion.

Key words: oxidation, kinetics, Fe₃Al, microcrystalline