The oxidation behavior of SiC fibers coated with (a) undoped polysilazane and (b) precursors containing a mixture of polysilazane and hafnium butoxide in equal weight fractions, is reported. The coatings were prepared by repetitive cycles of nanolayer depositions, as reported in recent publications. The oxidation experiments were carried out at 1400°C in ambient air (Boulder, CO) for up to 100 hours. The extent of degradation of SiC was measured by the recession in the diameter of the fibers as a function of time. The fibers with undoped polymer precursor recessed significantly, whereas the fibers coated with HfSiCNO remained essentially unchanged. These results are in agreement with earlier work from our laboratory where the resilience of hafnon and zircon, as well as hafnia and zirconia, against high‐temperature corrosion in streaming humid environments had been highlighted.

中文翻译：

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SiC纤维哈夫农抗氧化衰退的薄涂层

报道了涂覆有（a）未掺杂的聚硅氮烷和（b）包含等重量分数的聚硅氮烷和丁醇ha的混合物的前体的SiC纤维的氧化行为。如最近的出版物所报道，通过纳米层沉积的重复循环来制备涂层。氧化实验在环境空气（Boulder，CO）中于1400°C进行长达100小时。SiC的降解程度通过纤维直径随时间的变化来测量。具有未掺杂的聚合物前体的纤维明显凹陷，而涂覆有HfSiCNO的纤维基本上保持不变。这些结果与我们实验室早期的研究结果相吻合，该实验室中的哈农和锆石以及哈弗尼亚和氧化锆具有回弹力，