Study on Thermal Shock Resistance of Nano-CeO2–Y2O3 Co-Stabilized ZrO2 (CYSZ) Ceramic Powders Thermal Barrier Coating of Aircraft Engine

Abstract

In this paper, nano-CeO2–Y2O3 co-stabilized ZrO2 ceramic powders (CYSZ) were firstly prepared by co-precipitation method, and CYSZ powder was spray-granulated, followed by thermal plasma spraying of nano-CYSZ thermal barrier coating on 35Cr2Ni4 MoA alloy matrix. After XRD and SEM analysis, the five CYSZ ceramic coatings (CeO2 content 0, 1, 5, 10, 15 mol%) prepared were tetragonal phase structures before and after the thermal shock experiment, and the thickness of CYSZ ceramic coating was about 200 μm. Adding appropriate amount of nano CeO2 promoted the formation of micro-cracks in the coating, released the coating stress, slowed down the thermal shock damage process, and prevented the transformation from t-ZrO2 to m-ZrO2. The AFM morphology showed that the coating surface grains grow vertically after thermal shock cycle, which indicated that the entry of Ce4+ into ZrO2 lattice resulted in lattice distortion and made the grains more stable. When the content of CeO2 is 1 mol%, the thermal shock resistance excellent is 84 times. Therefore, the addition of CeO2 can effectively improve the thermal shock resistance performance of CYSZ thermal barrier coating, meeting the requirements of high temperature working conditions of aeroengine and hot-end components.