High temperature corrosion properties of SiNx and CrNx coatings deposited by IBAD method

SiNx and CrNx coatings (thickness 1-2 μm) were deposited by IBAD method at a nitrogen ions energy of 90 keV on low-alloy, AISI 310 and 316 substrate. The samples were subjected to long-term high temperature corrosion tests at cycled reducing-oxidizing atmosphere and in air. Corrosion rate was evaluated gravimetrically. The corrosion rate of coated alloy steels was significantly decreased at temperatures up to 800 °C. At 900 °C exposure the nitrides were subjected to fast decomposition and oxidation.