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用SEM／EDS，XRD,TEM／EDS等对1000℃下的Ni20Cr合金及其离子注Y（剂量分别为1×1015，2×1016和1×1017ions／cm2）后的氧化膜表面形貌、微观结构和氧化产物进行观测分析，确认氧化膜由具有较大晶粒尺寸的NiO，NiCr2O4尖晶石和较小晶粒尺寸的Cr2O3氧化物组成，且在部分NiO三角晶界处发现有空洞产生，注入Y剂量大于2×1016ions／cm2后，Cr的氧化产物的体积分数明显增多，并在其中探测到Y，它大多以含Y的氧化物小颗粒存在于Cr2O3氧化物层内，根据实验结果，认为在氧化初始，Y优先氧化形成细小的氧化物颗粒（10—20nm），这些小颗粒在随后的氧化过程中，一方面促进Cr2O3氧化物的形核和生长，另一方面通过自身微量溶解产生Y3＋并向氧化膜晶界偏聚，这不仅阻挡Cr3＋沿晶界的短路扩散，而且增强了氧化膜晶粒间的粘结力，进而降低氧化速率，提高了氧化膜的力学性能。
The surface morphologies of the oxide films were characterized by SEM / EDS, XRD, TEM / EDS, etc. at 1000 ℃ and Ni Structure and oxidation products were observed and analyzed to confirm that the oxide film is composed of NiO, NiCr2O4 spinel with larger grain size and Cr2O3 oxide with smaller grain size, and voids are found at some NiO triangular grain boundaries. When the dosage of Y is more than 2 × 1016ions / cm2, the volume fraction of oxidation products of Cr is obviously increased and Y is detected therein. Most of the oxide particles containing Y are present in the Cr2O3 oxide layer. According to the experimental results, At the initial oxidation stage, Y is preferentially oxidized to form fine oxide particles (10-20 nm). These small particles, on the one hand, promote the nucleation and growth of Cr 2 O 3 oxide on the other hand, and on the other hand produce Y 3 + And segregates to the grain boundaries of the oxide film. This not only blocks the short circuit diffusion along the grain boundaries of Cr3 +, but also enhances the adhesion between oxide grains, thereby reducing the oxidation rate and improving the mechanical properties of the oxide film.