Multilayered Thermal Barrier Coatings by CVD
Abstract
Turbine engine component life is currently limited by creep, creep-rupture, oxidation/corrosion, and thermomechanical fatigue. The use of protective coatings, such as nickel-chromium-aluminum-yttrium (NiCrAlY) and more recently platinum aluminides and various thermal barrier coatings (TBCs), has enabled higher temperatures and longer component life to be achieved, but component life and temperature capability still limit obtainable engine operating efficiency. Reduction in component temperature through the development and use of improved TBCs can dramatically extend component life, or conversely, allow higher operating temperatures to be used at constant component life. Additionally, lowering oxygen diffusion through the TBC will increase the life of the TBC itself, and reduce or eliminate oxidation and corrosion of the bondcoat and underlying component structure. Extension of TBC technology to increasingly complicated combustor, blade, and vane geometries and cooling passages requires improved application methods. In this project, Ultramet developed and demonstrated the chemical vapor deposition (CVD) of bondcoats and multilayered TBCs. Analytical modeling to quantify performance improvement predicted a 40-80 deg C drop in turbine blade temperature through the use of these coatings. In addition, burner rig oxidation and salt spray corrosion testing were performed on a coated blade.
Document Details
- Document Type
- Technical Report
- Publication Date
- May 01, 1997
- Accession Number
- ADA360822
Entities
People
- Andrew J. Sherman
- Arthur J. Fortini
- Sangvavann Heng