Characterization of functionally graded ZrO2 thermal barrier coatings sprayed by supersonic plasma spray with dual powder feed ports

The functionally graded thermal barrier coatings (FG-TBCs) with 80% ZrO2-13%CeO2-7%Y2O3 (CYSZ)/NiCoCrAlY were prepared using a recently developed supersonic plasma spraying (S-PS) with dual powder feed ports system. The thermal shock experiment of FG-TBCs specimens was carried out by means of the automatic thermal cycle device, in which the samples were heated to 1 200 °C by oxygen-acetylene flame jet then water-quenched to ambient temperature. The temperature—time curves of specimens and photographs can be watched online and recorded by a computer during the test. The results show that the totally 1 mm-thick FG-TBCs have excellent thermal shock resistance due to the fact that the coatings have no any peeling-off after 200 thermal cycles. The microstructures and morphologies of FG-TBCs were characterized and analyzed by SEM.