Creep and corrosion behaviors of bare and aluminized ferritic-martensitic substrates

摘要

Thin pack and chemical vapor deposited (CVD) aluminide coatings on commercial ferriticmartensitic Fe-9Cr-2W steel are being investigated by creep and corrosion testing at 650 deg C. Mass gain results indicate that these coatings are protective at 650 deg C in humid air. Comparison with bare material shows that the coated region makes no contribution to the creep strength. The consumption of metal due to the exposure in water vapor of uncoated specimens is compensated by the growth of a load-bearing oxide scale. Pre-oxidation of the alloy in humid air also affects the alloy microstructure.