The interaction of the Fe-32.7Mn-6.59Al-1.26Si-0.25C (wt.%) and Fe-323Mn-8.54Al-1.31Si-0.54C (wt.%) alloys with the environment was evaluated. Potentiostatic and total immersion tests, planned and analyzed by the statistic model of fixed effects were used for the evaluation of corrosion in gasoline, alcohol fuel, lactic acid solution (40 wt.%), sodium chloride solution Q wt.%), and boiler water. Potentiostatic tests in IN H2SO4 medium presented that the alloys showed a tendency towards passivation. The role that aluminum and silicon play in alloy corrosion mechanism was discussed. (c) 2004 Elsevier B.V. All rights reserved.