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The hot corrosion resistance of sprayed and atomized Fe40at.%Al, Fe40Al+0.1B and Fe40Al+0.1B+10Al2O3 iniennetallic materials have been evaluated in molten Na2SO4 at 900 and 1000 °C using polarization curves and polarization resistance measurements. The results are supported by electron microscopy and microchemical studies. The tests lasted 5 days. At 900 °C the Fe40Al material had the lowest corrosion rate (0-03 mA/cm2), and the Fe40Al+0.1B+10Al2O 3 exhibited the highest. At 1000 °C, the Fe40Al+0.1B material, was the material that had the best corrosion resistance with less than 0.02 mA/cm2 in the first 50 hours, whereas the Fe40Al presented the worst corrosion resistance with 0.20 mA/cm2. The results are discussed in terms of the establishment of an A12O3 layer that gives corrosion resistance to the materials and promotes an Al depletion in the FeAl matrix which allows the sulfides formation.