Influence of Al content and pre-oxidation on the aqueous corrosion resistance of binary Fe-Al alloys in sulphuric acid

摘要

The influence of Al content and pre-oxidation on the corrosion behavior of binary Fe-Al alloys in 0.0126 M H2SO4 was investigated. The minimum Al content for forming a passive film on binary Fe-Al at 25 degrees C is 15 at.% and passivation improves up to 25 at.% Al. X-ray photoelectron spectroscopy measurements show that the passive film on Fe-25Al is enriched in Al and consists of an outer layer of mixed Al and Fe hydroxides and an inner layer of Al oxide. The oxide layer generated at 1000 degrees C effectively protected against aqueous corrosion in H2SO4.