Abstract

Cr1-xAlxN/CrN/Cr multilayer films with a range of different Al contents were deposited on 9–12% Cr heat-resistant steel using direct current magnetron sputtering (DCMS). The chemical composition, roughness, cross-sectional structure, oxidation resistance and kinetic model of oxidation of the resulting films were investigated using various techniques. We discovered that Al atoms substituted for Cr atoms, while the crystal structure remained unchanged. Since Al doping decreases the lattice constants and hinders grain growth, the roughness of the film decreases, and the microstructure becomes denser, which is beneficial to the enhancement of oxidation resistance. According to the kinetic model, internal diffusion is the main restrictive step in this process. Increasing the Al content aids in the formation of an amorphous oxide surface layer that is abundant in Al. When the Al content is sufficiently high, the diffusion of oxygen into the 9–12% Cr steel substrates is prevented by the oxide surface layer of the film, which protects the substrates from further oxidation.

Full Text
Published version (Free)

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call