Faraday Technology is developing a non-line of sight, electrically mediated electrophoretic deposition process (Faradayic EPD) for thermal barrier coatings for use in gas turbines. This process has been shown to produce uniform coatings through the application of pulse and pulse-reverse electric fields that, when compared to traditional EPD, have an increased coating uniformity and decreased surface roughness due to a decrease in hydrolysis and edge effects brought about by better control of the electric field during deposition. A yttria-stabilized zirconia (8% YSZ) coating was deposited from a suspension onto Ni-based superalloy substrates that had an MCrAlY bond coat. The samples were then subjected to a binder burnout and sintering process and subjected to a battery of tests, including surface roughness measurements, microstructural examination, thermal conductivity measurements, thermal cycling tests, and other appropriate tests of merit, to determine the feasibility for use in gas turbine engines. The primary objective of this research is to develop the EPD process to produce TBCs with properties consistent with similar deposition methods.
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