Oxidation behavior of Fe40Al-xWC composite coatings obtained by high-velocity oxygen fuel thermal spray

The Fe40Al-xWC (x=0, 10, 12, 15) coatings with dense structure were successfully deposited by high-velocity oxygen fuel (HVOF) spraying of a mixture of Fe, Al and WC powders. The objective of the present work is to provide insight into the oxidation behavior of the as-deposited coatings at 650 °C under 0.1 MPa flowing pure O2. The present results show differences in the oxidation behavior of Fe40Al coating and Fe40Al-xWC composite coatings. The irregular Fe2O3 layer is seen on the top surface of the composite coatings. Fe40Al coating and Fe40Al-15WC composite coating both suffer a catastrophic corrosion due to the formation of a porous structure during 24 h of oxidation. However, Fe40Al-10WC and Fe40Al-12WC composite coatings show a good oxidation resistance behavior due to their dense structure.