High-temperature oxidation of a model γ′-Ni3Al-based Ni–20Al–5Cr alloy and versions of this alloy doped with Y, Hf, or Si, or some combination of these, was investigated. Oxide scale evolution was characterized using SEM, TEM, and TOF–SIMS. The resulting scale microstructures depended quite sensitively on the heating rate to the oxidation temperature of 1100 °C. However, whatever the heating rate, the dopant additions improved the oxidation resistance of the base alloy. The reactive elements Y and Hf, if segregated to the surface during preheating under conditions where appreciable oxidation was not possible, suppressed transient oxidation and facilitated the exclusive growth of the thermodynamically stable α-Al2O3 scale.

中文翻译：

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γ'-Ni3Al基Ni-20Al-5Cr合金在不同加热条件下含和不含活性元素的氧化行为

研究了基于 γ'-Ni3Al 模型的 Ni-20Al-5Cr 合金以及该合金的掺杂 Y、Hf 或 Si 或这些合金的某些组合的高温氧化。使用 SEM、TEM 和 TOF-SIMS 表征氧化层演变。由此产生的氧化皮微观结构非常敏感地取决于加热速率到 1100 °C 的氧化温度。然而，无论加热速率如何，掺杂剂的添加都提高了基体合金的抗氧化性。反应性元素 Y 和 Hf，如果在不可能进行明显氧化的条件下预热期间分离到表面，则会抑制瞬态氧化并促进热力学稳定的 α-Al2O3 水垢的独家生长。