Preparation and Thermophysical Properties of CeO2–Gd2O3 Co–Stabilized Zirconia Coating Prepared by Solution Precursor Plasma Spray

Solution precursor plasma spray (SPPS) is a novel coating deposition process that uses solution precursors as starting materials rather than ceramic or metal powders. In this work, CeO2-Gd2O3 co-stabilized ZrO2 (CGSZ) thermal barrier coating (TBC) was prepared by SPPS process. The microstructure of the coating was optimized by adjusting different processing parameters (such as plasma power, spray distance, precursor concentration). The phase composition and microstructure of the CGSZ coating were characterized by X-ray diffraction (XRD) and scanning electron microscope (SEM). The experimental results showed that, the CGSZ coating with better deposition rate and typical microstructures, such as vertical-cracks and IPB (inter-pass boundary) structure, was successfully prepared under precursor concentration 1.5mol/L, spray distance 35 mm, and gun ppower 45 kw, respectively. The as-sprayed CGSZ coating has a pure tetragonal structure at 1400oC. The thermal conductivity of the coating was determined by laser flash method, and it is much lower than that of the conventional 8YSZ coating.