Oxygen diffusion mechanisms during oxidation of ZrB₂-30 vol% SiC were explored at temperatures of 1500°C and 1650°C using an ¹⁸O tracer technique. Double oxidation experiments in ¹⁶O₂ and ¹⁸O₂ were performed using a modified resistive heating system. A combination of scanning electron microscopy, energy-dispersive spectroscopy, and time-of-flight secondary ion mass spectrometry was used to characterize the borosilicate and ZrO₂ oxidation products. Oxygen exchange with the borosilicate network was observed to occur quickly at the oxygen-borosilicate surface at both 1500°C and 1650°C, while evidence of oxygen permeation was only observed at 1650°C for short time (<1 min) exposures. At longer times, >5-9 min, complete oxygen exchange throughout both the borosilicate glass and ZrO₂ was observed at both temperatures preventing identification of the oxygen transport mechanisms, but demonstrating that oxygen transport is rapid in both oxide phases.

中文翻译：

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ZrB2-SiC高温氧化过程中的氧扩散机理

使用¹⁸ O示踪技术探索了在1500°C和1650°C的温度下ZrB ₂ -30 vol％SiC氧化过程中的氧扩散机理。使用改进的电阻加热系统在¹⁶ O ₂和¹⁸ O ₂中进行了双重氧化实验。结合使用扫描电子显微镜，能量分散光谱和飞行时间二次离子质谱法来表征硼硅酸盐和ZrO ₂氧化产物。在1500°C和1650°C的氧-硼硅酸盐表面观察到与硼硅酸盐网络的氧交换迅速发生，而只有在短时间（<1分钟）暴露下才在1650°C观察到氧渗透的迹象。在更长的时间，> 5-9分钟，在两个温度下都观察到整个硼硅酸盐玻璃和ZrO _2的完全氧交换，阻止了氧传输机制的确定，但证明了在两个氧化物相中氧的传输都是快速的。