Synchrotron radiation photoemission study of the passive layers of heat treated Fe3Al-type alloy

Abstract

We report on a synchrotron radiation photoemission study of an Fe3Al-type alloy. The influence of different annealing treatments on the surface electronic structure has been investigated. The Al-2p photoemission spectra show slight differences among samples with a very small metallic Al component. From the Fe-3p and the valence band photoemission spectra, a higher surface Fe-content for the sample having a defective ordered B2 structure is observed. This finding is explained in terms of the bulk structure and the thickness of the passive layer. After determination of the surface composition of the samples, electrochemical experiments in Hank's solution have been performed in order to determine the influence of the passive layer composition on the corrosion behaviour of the samples. The low corrosion rates observed for all specimens indicate that the passive layer formed in air on the material surface gives high corrosion protection to the alloy for all heat treatments. © 1997 Elsevier Science Ltd. All rights reserved.