Influence of boron contents on oxidation behavior and the diffusion mechanism of Fe–B based alloys at 1073 K in air

Abstract

The microstructure and oxidation behavior of Fe–B alloys have been investigated. Oxide scale cross-sectional microstructures oxidized at 1073K for 100h have been studied. EPMA investigations show that B2O3–SiO2 oxides accumulates in the inner oxide layer which improves the oxidation behavior and oxide layer adhesion considerably. Cyclic oxidation kinetics data indicates that Fe–B 3.08wt.% alloy presents the best oxidation resistance. The formation of diffusion zone in the Fe–B alloys indicate that the oxidation of the Fe2B boride is controlled by boron diffusion. The diffusion zone increases with time and reaches a maximum width of 60–65μm.