The effect of silicon on the oxidation behavior of iron aluminide produced using powder metallurgy

Iron aluminides are widely considered the most important materials due to their lightweight, low cost, easy sintering, and resistance to oxidation and sulfidation. The presence of silicon in some alloys containing aluminum has had positive effects on their oxidation resistance. Few researchers have addressed the effect of silicon on the oxidation behavior of iron aluminide which is formed using elemental powders of Fe, Al, and Si. Therefore, in this research, the amount of silicon was changed and the effects of Si content on the oxidation behavior of iron aluminide were investigated. To achieve this goal, the elemental powders of Fe and Al (with a molar ratio of 1:1) along with different amounts of Si were pressed and sintered at 950°C. The samples were oxidized in air at temperatures of 600°C, 700°C, and 800°C, consequently. The findings confirm that silicon up to a certain content can improve the oxidation resistance of iron aluminide. The morphology of the obtained phases is influenced by the amount of silicon as well.