About this Abstract |
Meeting |
MS&T22: Materials Science & Technology
|
Symposium
|
High Temperature Oxidation of Metals and Ceramics
|
Presentation Title |
Thermochemical Stability of High Entropy Rare Earth Oxide (HERO) Coatings for Refractory Alloys |
Author(s) |
Kristyn Diane Ardrey, Elizabeth Opila, Patrick Hopkins, Bicheng Zhou, Prasanna Balachandran |
On-Site Speaker (Planned) |
Kristyn Diane Ardrey |
Abstract Scope |
High entropy rare earth oxide (HERO) coatings are under investigation for application on Nb-base alloys to increase operating temperatures in aircraft turbine engines. Nb-base alloys are the most formable of the refractory alloys, but they lack the ability to form a protective oxide layer, making an environmental barrier coating essential. Potential coating candidates for use in a combustion environment are rare earth oxides. Rare earth oxides have a similar thermal expansion with Nb-base alloys and provide thermochemical stability in a combustion environment, giving them the ability to act as an environmental barrier coating (EBC). Furthermore, with the high entropy approach, thermal conductivity may be reduced by mixing multiple rare earth oxides into a single HERO coating, providing dual thermal/environmental barrier coating capability. This presentation will focus on the effect of HERO coating composition on thermochemical stability in turbine environments and interactions with the underlying Nb-base alloy during high temperature exposures. |