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研究了Co－40Cr（wt％）合金在空气中、1000℃下的恒温氧化和循环氧化行为。通过SEM／EDXA等测试手段，对合金表面形成的氧化膜进行了分析．并且，与合金表面离子注入3×1016Y+／cm2和3×1017Y+／cm2后的氧化行为进行了比较．结果表明，注钇和未注钇样品氧化后表面形成的都是纯Cr2O3膜，离子注钇明显改善了合金的氧化性能．其原因主要是稀土钇能以离子或细小氧化物颗粒的形式偏聚于Cr2O3晶界，通过阻碍氧化膜中Cr3＋阳离子向外扩散，降低了氧化膜的生长速率．同时，通过阻碍氧化膜／合金界面附近“kirkendall”空洞的形成，增强了氧化膜与合金基体之间的结合强度，提高了氧化膜的粘附性及合金的抗氧化性能．
The oxidation and cyclic oxidation behavior of Co-40Cr (wt%) alloy in air at 1000 ℃ were investigated. By SEM / EDXA and other testing methods, the oxide film formed on the surface of the alloy was analyzed. The oxidation behavior of the alloy surface after ion implantation of 3 × 1016Y + / cm2 and 3 × 1017Y + / cm2 was also compared. The results show that the pure Cr2O3 films are formed on the surface of the yttrium-doped and un-yttrium-yttrium-doped samples, and the yttrium-doped yttrium significantly improves the oxidation performance of the alloy. The reason is that rare earth yttrium can segregate in the form of ions or fine oxide particles on the Cr2O3 grain boundaries, and the growth rate of the oxide film is reduced by hindering the outward diffusion of Cr3 + cations in the oxide film. At the same time, the adhesion strength between the oxide film and the alloy matrix is enhanced and the oxidation resistance of the oxide film is improved by hindering the formation of the void of the “kirkendall” near the oxide film / alloy interface.