Thermal barrier coatings (TBCs) are widely used in the hot end components of advanced aero-engines

effectively prolong the service life of the hot end components

and become essential thermal protection materials for advanced aero-engines. However

in the process of service

some atmospheric sediments CMAS became molten after heating and adsorbed on the surface of the thermal barrier coating

and penetrated into the coating along the defects such as pores and cracks

leading to premature failure of the coating. YSZ thermal barrier coating was prepared by plasma spraying–physical vapor deposition (PS–PVD). XRD

SEM and other characterization methods were used to characterize the phase composition and microstructure of the coating with different corrosion time. The results show that YSZ coatings undergo phase transition after CMAS corrosion at 1250 ℃ . With the increase of corrosion time

CMAS sediments will penetrate into the interior along the columnar crystal gap of the thermal barrier coating

resulting in loose coating structure

columnar crystal fracture phenomenon in the upper region of the ceramic layer

and the coating macro performance is part of the ceramic layer spalling. After 8 h of corrosion

columnar crystals appear in some areas of the ceramic layer and peel off from the bonding layer. The penetration depth of CMAS increases with the increase of corrosion time. The penetration rate of CMAS is relatively fast within 3 h of corrosion

but becomes relatively slow after 3 h of corrosion.