Abstract
The high temperature oxidation behavior of plasma sprayed chromium boride-chromium carbide composite coatings had been studied in this work. In-situ and ex-situ CrB2-Cr3C2 composite coatings were prepared by plasma spraying Cr-B4C and CrB2-Cr3C2 composite powders, respectively. The changes of microstructure and phase of two coatings after oxidation at different temperature and time were studied. After oxidation at 850 °C for 10 h, the in-situ Cr-B4C coating had a thinner oxide layer (8–10 μm) and a lower weight gain rate (0.023%) than ex-situ CrB2-Cr3C2 coating. This is because the density of Cr-B4C coating was high, and the oxidized glass phase B2O3 gradually filled the pores of the coating at 850 °C. For oxidation of CrB2-Cr3C2 coating at 1000 °C for 10 h, since the evaporation rate was higher than the generation rate of liquid oxide layers, a large penetration cracks damaged the integrity of the coating surface, which would not hinder oxygen into the coating. The Cr-B4C coating had better oxidation resistance after oxidation at 1000 °C for 10 h, because more phases with low oxygen permeability were formed in the coating, and the generation rate of the oxide film was higher than the evaporation rate.
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 callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
