Abstract: In order to meet the technical requirements for high-temperature thermal protection of thermal barrier coatings on DD6 single crystal blades used in aviation engines, NiCoCrAlY metal bonding layer was prepared on the DD6 single crystal substrate using multi-arc ion plating technology, and single-layer and double-layer ceramic surface layers were prepared using electron beam physical vapor deposition technology. The influence of the coating on the oxidation resistance and interface microstructure evolution mechanism of DD6 single crystal was studied. The results show that under static antioxidant conditions at 1100 ℃, a dense and continuous TGO（thermal growth oxide） layer is formed on the surface of the bonding layer after DD6 single crystal coating, and the coating exhibits excellent high-temperature oxidation resistance. The uncoated DD6 single crystal surface forms a 20-40 μm non-dense oxide film containing Ni, Co, and O spinel phases, and the surface oxide film exhibits local peeling phenomenon. The thickness of TGO layer in dual ceramic coating is thinner than that in single ceramic layer, mainly due to the lower thermal conductivity of dual ceramics, which can shorten the time when the TGO layer interface is under high temperature conditions,thereby causing the growth of TGO layer to become slower.The TGO layer is mainly composed of Al₂ O₃ and contains a small amount of Hf O₂ rich precipitates inside. A small amount of Cr element appears at the interface of the single ceramic layer. After coating with a low thermal conductivity ceramic layer, the growth of the TGO layer is delayed due to its lower thermal conductivity. The absence of Cr element in the TGO layer indicates that there is no depletion of Al element. The application of low thermal conductivity ceramic layer can further extend the service life of thermal barrier coatings and provide technical support for the application of new low thermal conductivity thermal barrier coatings.