OXIDATION OF Fe-Y ALLOYS AT 600-800''C IN AIR
Fe—Y合金在600—800℃空气中的氧化行为

The oxidation behaviors of Fe-Y alloys containing 2at% and 5at. %Y respec- tively and pure iron have been studied at 600--800'C in air. Fe-2Y and Fe-5Y alloys were oxidized slower than pure Fe at the three temperatures. The oxidation of pure iron followed a parabolic rate law. The oxidation of Fe-Y alloys at 600'C followed an approximately parabolic rate law, but not at 700 and 800'C where the oxidation went through several stages with quite different rates. The oxide scales grown on Fe-2Y and Fe-5Y alloys at 700 and 800'C were composed of an external pure Fe oxides containing Fe203, Fe304 and FeO among which FeO constituted the main iron oxides, and an inner mixture of ,FeO and YFeO,. The scales grown on Fe-2Y and Fe-5Y at 600'C mainly consisted of Fe203, Fe,04 and Y203 with little FeO. Significant internal oxidation in both Fe-Y alloys was observed at the three tem- peratures. The Y-containing oxides followed the distribution of the original intermetallic compound phase in the alloys. The effects of Y on the oxidation of pure Fe are discussed.