Abstract Model alloys Fe-20Cr and Fe-20Cr-0.5Si (wt.%) were exposed to Ar-20CO2 and Ar-20CO2-20H2O gas mixtures at 650 and 818 °C, forming Cr2O3 scales. Impurities segregated to chromia grain boundaries: carbon at sub-monolayer level, iron as spinel in narrow (10–20 nm) bands alongside the boundaries and silicon as dispersed glassy SiO2 nanoparticles. Thermodynamic driving forces for development of these nanostructures and enabling transport processes are identified. The consequences for grain boundary diffusion supporting scale growth and alloy carburisation are discussed.

中文翻译：

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CO 2 气中生长的氧化铬鳞片晶界杂质偏析的原子探针研究

摘要 模型合金 Fe-20Cr 和 Fe-20Cr-0.5Si (wt.%) 在 650 和 818 °C 下暴露于 Ar-20CO2 和 Ar-20CO2-20H2O 气体混合物中，形成 Cr2O3 水垢。杂质分离到氧化铬晶界：亚单层水平的碳，铁作为尖晶石在边界旁边的窄（10-20 nm）带和硅作为分散的玻璃状 SiO2 纳米粒子。确定了开发这些纳米结构和实现传输过程的热力学驱动力。讨论了支持氧化皮生长和合金渗碳的晶界扩散的后果。