Kinetics of the interaction of aluminized 12X18H10T steel with the molten carbonates of alkaline metals

Corrosion of aluminized 12X18H10T steel in a melt of potassium and lithium carbonates at 650 degrees C in a CO2-O-2 atmosphere was investigated in time, by means of polarization curves, x-ray diffraction, microspectroscopic, chemical, and metallographic analysis methods. The aluminization of the steel was carried out in a halide melt with aluminum powder at 600 degrees C for 8 h. An oxide layer of 10-15 mu m in thickness was shown to form on the aluminized surface, while the average corrosion rate decreases with time, the aluminum content in the coating decreases; the passivation performance deteriorates, especially at more than 1000 h exposure; and the thicknesses of coating and oxide layer do not substantially change.