Abstract
The oxidation behavior of SiC-ZrB2-ZrC coating on C/C composites was investigated, basing on the microstructure evolution of oxide scale under different oxygen partial pressures at 1773 K. Similar experiments were conducted in SiC coatings, ZrB2 and ZrC ceramic sheets for comparison. The multiphase coating showed the better oxidation resistance at a higher oxygen partial pressure, and its mass change was 1.34% after isothermal oxidation for 6 h at an oxygen partial pressure of 80,000 Pa. With the increase of the oxygen partial pressure, ZrO2 particles with fibrous denticles were replaced by the aggregations of ZrO2 particles and more SiO2 glass was formed in a short time. The formed SiO2 glass could effectively heal the microcracks of oxide scale. Moreover, the ZrB2 and ZrC phases played an important role in deflecting cracks and restraining the propagation of cracks during oxidation. As the oxygen partial pressure increased, the oxide scale of SiC-ZrB2-ZrC coating became denser, presenting a two-layered structure composed of a SiO2 layer and a Si-O-Zr layer at the elevated oxygen partial pressure.
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.
