Non-Line-of-Sight Coating Of Turbine Airfoils

Thermal barrier coatings (TBC) are desired to improve the durability of hot-section engine components. Currently, TBC top coats are applied onto turbine components using an electron beam physical vapor deposition (EB-PVD) process. A key drawback of this approach is that it can only effectively coat surfaces in the line-of-sight of the vapor source. The advent of advanced engine designs containing complex components with many hidden surfaces have resulted in a need for TBC deposition techniques which can effectively deposit high quality coatings onto the non line-of-sight (NLOS) regions of components. In this work, we will use novel coating techniques that increase the growth rate of TBC coatings in NLOS regions and also result in the required coating microstructure. The proposed Phase I effort will demonstrate the key performance attributes of the process by applying TBCs onto superalloy substrates aligned NLOS to the vapor source. This will lead to a follow-on Phase II program focused on using the new deposition process to apply TBC coatings onto real aircraft components having NLOS region. The end result will be process the can apply next generation TBC coatings onto a wider range of complex engine components in a cost effective manner.