目的 系统地评价典型高温防护涂层的抗高温氧化性能，并分析其失效机制。方法 通过对比普通NiAl涂层、NiCrAlY涂层、Pt改性NiAl涂层以及Pt+Hf共改性NiAl涂层等四种典型高温防护涂层在1100 ℃的恒温氧化行为，从氧化过程中的氧化增重、组织结构演变规律等角度出发，分析了四种涂层在高温氧化过程中的抗氧化性能以及氧化失效规律。结果 四种涂层在1100 ℃恒温氧化过程中的增重均符合抛物线规律。普通NiAl涂层氧化膜粘附性能较差，氧化膜快速剥落，涂层退化最快。NiCrAlY涂层中Y元素在氧化膜/涂层界面形成“钉扎”作用，显著提高氧化膜的粘附性能，但由于涂层内部Al元素含量降低，涂层1100 ℃氧化300 h后基本失效。Pt改性NiAl涂层的氧化膜较为完整，但氧化膜起伏严重。Pt+Hf共改性NiAl涂层的氧化膜均匀完整且无明显起伏，具有综合最优的抗高温氧化性能。结论 四种涂层的抗高温氧化性能排序为：Pt+Hf共改性NiAl> Pt改性NiAl>普通NiAl >NiCrAlY。

The work aims to evaluate the isothermal oxidation resistance of typical high-temperature protective coating systematically and analyze their failure mechanism. Isothermal oxidation performance of plain NiAl, NiCrAlY, Pt modified NiAl and Pt+Hf co-modified NiAl were compared at 1100 ℃. Isothermal resistance and failure mechanisms of four typical coatings were analyzed in terms of the mass gain and microstructure evolution during the oxidation test. The mass gain of four coatings during oxidation 1100 ℃ conformed to the parabolic laws. Plain NiAl coating degenerated fastest due to the poor adherence of oxide scale. The oxide scale adherence for NiCrAlY was satisfactory due to the formation of oxide “tags” by the existence of Y, but it almost lost the protection ability completely after 300 h exposure due to the lower Al content in the coating. Pt modified NiAl displayed integrated oxidation resistance, but had the serious rumpling. In contrast, the oxide of Pt+Hf co-modified NiAl was uniformly and kept stable during the exposure and manifested the best oxidation resistance. The oxidation resistance of the four typical high-temperature coatings can be ranked as: Pt+Hf co-modified NiAl > Pt modified NiAl > plain NiAl > NiCrAlY.