The Corrosion of an Amorphous Fe 70 C 10 P 10 B 5 Mo 5 Alloy in Various CO 2 /CO Mixed Gases at 500 °C

The corrosion behavior of an Fe 70 C 10 P 10 B 5 Mo 5 amorphous ribbon was investigated in various CO 2 /CO mixed gases within the oxygen partial pressure range 7.2 × 10 −24 to 7.2 × 10 −22 Pa at 500 °C. In general, the amorphous alloy exhibited exclusive oxidation throughout the study, and its oxidation kinetics followed the parabolic rate law. The parabolic rate constants steadily increased with increasing oxygen pressure, indicating a typical scaling behavior for p-type semiconductivity. The scale formed on the glassy alloy consisted mostly of Fe 3 O 4 and a minor amount of B 2 O 3 , and the formation of B 2 O 3 is responsible for the lower scaling rate of the glassy alloy as compared with that of pure Fe.