The passivation behavior of Fe-Al alloys (3.4, 10.4, 18.7, 19.4, 29.5, and 41.7 at % Al) and Fe-Al alloys (19.5 and 29.0 at % Al) with 5.1 at % Cr addition in 0.1 N H2SO4 is reported in this paper. The behavior has been evaluated by potentiodynamic polarization measurements. The results show the Fe-Al alloys, which the Al content of alloy exceeds 19 at %, have wide passivation regions with low passivation current. However, when the Al content of Fe-Al alloys exceeds this range, the increment of Al content has slight influence on passivation behavior compared with ternary Cr addition. (c) 2006 Springer Science + Business Media, Inc.