Nitride based Nanocomposite Bond Coat for SiC/SiC CMCs (17-RD-936)

This Phase II SBIR program seeks to continue development of a high temperature nitride-based bond coat/alternative EBC system that will enable increased engine operation temperatures as well as alleviate surface recession of SiCf-SiC ceramic matrix composites (CMC). EBCs have been applied to the SiCf-SiC CMCs hot sections of aircraft turbine engines to mitigate active oxidation, increase fuel efficiency, and to extend the life of CMC components; however, issues related to the upper temperature limit and the material recession in the presence of high temperature water vapor remain. These issues are closely linked to the low thermal stability of the bond coat in SOA EBC systems and the active oxidation. Due to this fact, current efforts are focused on developing new bond coat alloys with use temperature up to 2700oF or higher, along with an alternative EBC top coat. We propose the development of a new high temperature (>2700oF) EBC system (bond coat/EBC top coat) to achieve a high fuel efficiency and a longer lifetime.