Corrosion Resistance of Aluminized Diffusion coating for Fe-25Cr-20Ni steel

Abstract

High-temperature corrosion resistance and characteristics of Fe-25Cr-20Ni steel was studied at 800 oC in air and (N2/H2O/H2S)-mixed gas condition up to 100 hours. The weight gain of each test coupon after the oxidation and (N2/H2O/H2S)-mixed gas corrosion test was measured using a micro-balance. The corroded test coupons were characterized by a SEM, an EDS, an XRD with Cu-Kα radiation, and an EPMA. As a result of the experiments, aluminized diffusion coating was formed the FeAl2 intermetallic phases. Thus aluminized diffusion coated Fe-25Cr-20Ni steel has reasonable corrosion resistance, because it can form a protective alumina scale, such as α-Al2O3 layer.