Abstract Present work aims to find the influence of carbide precipitates on the oxidation behaviour of Nb-rich Ni-Cr-Fe alloys at 1000 °C in air. Three Ni-Cr-Fe alloys, NC-15Fe-1Nb, NC-15Fe-1Nb-0.8C, NC-15Fe-1Nb-0.8C-0.5Ti were designed by alloying with Ti, Nb and C. Results show that the formation of NbC is crucial for the preferential oxidation of Cr. Moreover, either preventing NbC formation or favouring (Ti,Nb)C formation is found detrimental on such a beneficial effect, where the latter has a more intense influence. Roles of the precipitates in oxidation mechanism give new insights into the alloy optimization.

中文翻译：

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富铌 Ni-Cr-Fe 合金的氧化行为：碳化物析出物的作用和影响

摘要 目前的工作旨在研究碳化物析出物对富Nb Ni-Cr-Fe 合金在1000 °C 空气中氧化行为的影响。通过与 Ti、Nb 和 C 合金化设计了三种 Ni-Cr-Fe 合金，NC-15Fe-1Nb、NC-15Fe-1Nb-0.8C、NC-15Fe-1Nb-0.8C-0.5Ti。结果表明形成NbC 对 Cr 的优先氧化至关重要。此外，发现阻止 NbC 形成或有利于 (Ti,Nb)C 形成对这种有益效果是不利的，而后者具有更强烈的影响。沉淀物在氧化机制中的作用为合金优化提供了新的见解。