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研究了Ｎｉ－１１，８２Ａｌ－１．０３Ｚｒ－０．１Ｂ（ｗｔ－％）合金晶粒尺寸为３０和１８０μｍ两种组织结构试样，在９００和１１００℃静态空气中的等温氧化行为．发现，当氧化温度为９００℃时，氧化速率随晶粒尺寸减小而减小，而在１１００℃，二者氧化速率几乎没有区别．利用ＥＰＭＡ，ＸＲＤ分析了氧化产物，证明两种试样的氧化膜相成分与结构，均由ＮｉＯ外层和Ａｌ_２Ｏ_３，ＮｉＡｌ_２Ｏ_４内层组成．但氧化膜／合金界面形貌显著不同．９００℃氧化膜与合金界面呈平滑的波浪型，而１１００℃界面出现树根状突出氧化物伸入到合金表层内部．对上述实验结果作了理论分析，认为前一结果为合金晶界快速短路扩散传质所致、而后一现象与合金晶粒尺寸关系较小，起决定作用的为活性元素Ｚｒ的“反应元素效应（ＲＥＥ）”．
The isothermal oxidation behavior of Ni-11,82Al-1.03Zr-0.1B (wt-%) alloy in two kinds of microstructures with grain sizes of 30 and 180μm was investigated in static air at 900 and 1100 ℃. It is found that when the oxidation temperature is 900 ℃, the oxidation rate decreases with the decrease of grain size. At 1100 ℃, there is almost no difference between the two oxidation rates. The oxidation products were analyzed by EPMA and XRD. It was proved that the phase composition and structure of oxide film of the two samples were composed of the outer layer of NiO and the inner layer of Al_2O_3 and NiAl_2O_4. However, the oxide film / alloy interface morphology is significantly different. At 900 ℃, the interface between the oxide film and the alloy showed a smooth wave pattern, while the root-like protruding oxide appeared at the interface of 1100 ℃ and extended into the alloy surface. The above experimental results are theoretically analyzed. It is considered that the former result is caused by the rapid short-circuit diffusion and mass transfer at the grain boundaries of the alloy, and the latter phenomenon has little to do with the grain size of the alloy. The “reaction element effect” (REE) ".