Abstract
Direct supercritical CO2 (sCO2) power cycles require structural materials compatible with hot sCO2 containing high levels of water and oxygen impurities. Chromia-forming Ni-based superalloys, which are leading candidates at temperatures > 600 °C, have shown good compatibility in pure sCO2, however potential impurity effects are not well understood. Herein we exposed several commercial Ni-based alloys to 95%CO2-4%H2O-(1−3)%O2 at 750 °C and 0.1 or 20 MPa for 2500 h. Protective chromia scales formed in all cases. Nevertheless, water vapor-assisted oxide volatilization clearly occurred at high pressure. The volatilization rates decreased with time, but still represent a potentially serious compatibility issue in real, high-velocity, sCO2 systems.
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.
