Iron aluminide coating layers were formed on a ferritic martensitic grade 9Cr-1Mo (P 91) steel using pack aluminizing process. The formation of different aluminide compositions such as orthorhombic-Fe₂Al₅, B2-FeAl and A2-Fe(Al) on the pack chemistry and heat treatment conditions have been established. About 4-6 µm thick Al₂O₃ scale was formed on the FeAl phase by controlled heat treatment. The corrosion tests were conducted using both the FeAl and Al₂O₃/FeAl coated specimens in an electromagnetic pump driven Pb-17Li Loop at 500°C for 5000 h maintaining a flow velocity of 1.5 m/s. The detailed characterization studies using scanning electron microscopy, back-scattered electron imaging and energy dispersive spectrometry revealed no deterioration of the coating layers after the corrosion tests. Self-healing oxides were formed at the cracks generated in the aluminide layers during thermal cycling and protected the base alloy (steel) from any kind of elemental dissolution or microstructural degradation.