Electron Beam/Physical Vapor Deposition (EB/PVD) Coating Process Mapping for Complex Shapes

Thermal barrier coating are currently employed to thermally protect gas turbine engine components from high gas inlet temperatures to moderately improve the performance (fuel efficiency and thrust) of these engines. Enhanced benefits are envisioned in future TBC systems provided TBC durability can be reliably improved. One approach achieve more reliable TBCs is the development of non destructive methodologies to determine processing / structure / property relationships for electron beam-physical vapor deposited (EB-PVD) thermal barrier coatings (TBC) in both an ex-situ and in-situ manner. This would enable the creation of comprehensive process maps that could be used along with real time feedback during manufacturing to greatly enhance the capabilities of an EB-PVD system to reliably produce high quality TBC coatings. To achieve this, Directed Vapor Technologies International (DVTI) and ReliaCoat Technologies (RCT) will investigate the use of a curvature measurement technique to non-destructively determine critical, design related mechanical properties of EB-PVD deposited coatings and link these properties to processing parameters and coating performance. In Phase I, the apparatus and relevant analysis will be addressed. In Phase II, the applicability of the approach for in-situ measurements will be explored along with a utility of the apparatus in process development and optimization. BENEFIT: This research is anticipated to establish advanced process maps for EB-PVD based TBC processing techniques which can be used in conjunction with novel ex-situ and in-situ curvature measurement techniques to enable improved TBC properties to establish more optimal conditions for EB-PVD processing which could be applied with tighter lifetime distributions. These developments significantly increase the potential for TBC coatings to become prime reliant which would result in much greater gas turbine engine performance. This would help enable the realization of advanced gas turbine engine designs while leading to several percent thrust improvement or specific fuel consumption reduction for current turbine engines. These advances will not only benefit military engines, but also commercial and industrial gas turbines. In addition, the innovative approach proposed here will reduce the time and expense for refurbishing and repairing blades during engine overhauls, thus improving military readiness and reducing the cost of maintaining commercial aircraft.