In order to improve the high-temperature service property of Ir, a well-bonded single-layer pure IrAl intermetallic coating was prepared on Ir by pack cementation followed by vacuum annealing treatment. The oxidation behavior of the IrAl coating was investigated by cyclic oxidation tests at 1400–2000 °C and compared with that of pure Ir. The results showed that the IrAl coating, although containing many cracks, exhibited excellent oxidation resistance over the whole experimental temperature range. The reasons were deduced to be the in situ formation of Al2O3 and the sintering of the cracks in the IrAl layer. The excellent oxidation protective effect of the single-layer IrAl coating can be ascribed to its stable and unique as-oxidized microstructure, i.e., double-layer structure of Al2O3/Ir′, which showed excellent compatibility and comprehensive property.

中文翻译：

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单层 IrAl 金属间化合物涂层的高温氧化行为

为了提高Ir的高温使用性能，在Ir上通过填充渗碳和真空退火处理制备了结合良好的单层纯IrAl金属间化合物涂层。通过在 1400-2000 °C 下的循环氧化试验研究了 IrAl 涂层的氧化行为，并与纯 Ir 进行了比较。结果表明，IrAl 涂层虽然含有许多裂纹，但在整个实验温度范围内表现出优异的抗氧化性。推断原因是Al2O3的原位形成和IrAl层中裂纹的烧结。单层 IrAl 涂层优异的抗氧化效果可归因于其稳定且独特的氧化态微观结构，即 Al2O3/Ir' 双层结构，