Corrosion Resistance of Boiler Tubes in High Temperature Flue Gas and Ash

High-temperature simulation corrosion tests, corrosion morphology observation and composition analysis of corrosion products were used to study the corrosion behavior of 304 stainless steel, T91 stainless steel, and TP347 stainless steel in the simulated combustion of Zhundong coal. The results showed that the corrosion resistance of 304 stainless steel was similar to that of TP347 stainless steel, which was better than that of T91 stainless steel. The formation of Cr-containing oxide layer on the surface of 304 stainless steel improved the high temperature corrosion resistance of the samples. The low-melting point eutectic Ni₂S₃ formed on TP347 stainless steel in SO₂ atmosphere would cause the reactants to diffuse in the corrosion layer, which would lead to more serious corrosion than that of 304 stainless steel. T91 stainless steel had the lowest Cr content, so its corrosion resistance was the worst.