Li Lanlan, He Yingping, Xu Lida, Shao Chenhe, He Gonghan, Sun Daoheng, Hai Zhenyin
Department of Mechanical and Electrical Engineering, School of Aerospace Engineering, Xiamen University, Xiamen 361102, China.
Fujian Micro/Nano Manufacturing Engineering Technology Research Center, Xiamen University, Xiamen 361102, China.
Polymers (Basel). 2023 Aug 7;15(15):3319. doi: 10.3390/polym15153319.
Polymer-derived ceramic (PDC) thin-film sensors have a very high potential for extreme environments. However, the erosion caused by high-temperature airflow at the hot-end poses a significant challenge to the stability of PDC thin-film sensors. Here, we fabricate a thin-film coating by PDC/TiB/B composite ceramic material, which can be used to enhance the oxidation resistance and ablation resistance of the sensors. Due to the formation of a dense oxide layer on the surface of the thin-film coating in a high-temperature air environment, it effectively prevents the ingress of oxygen as a pivotal barrier. The coating exhibits an exceptionally thin oxide layer thickness of merely 8 μm, while its oxidation resistance was rigorously assessed under air exposure at 800 °C, proving its enduring protection for a minimum duration of 10 h. Additionally, during ablation testing using a flame gun that can generate temperatures of up to 1000 °C, the linear ablation rate of thin-film coating is merely 1.04 μm/min. Our analysis reveals that the volatilization of BO occurs while new SiO is formed on the thin-film coating surface. This phenomenon leads to the absorption of heat, thereby enhancing the ablative resistance performance of the thin-film sensor. The results indicate that the thin-film sensor exhibits exceptional resistance to oxidation and ablation when protected by the coating, which has great potential for aerospace applications.
聚合物衍生陶瓷（PDC）薄膜传感器在极端环境中具有很高的潜力。然而，热端高温气流造成的侵蚀对PDC薄膜传感器的稳定性构成了重大挑战。在此，我们通过PDC/TiB/B复合陶瓷材料制备了一种薄膜涂层，可用于提高传感器的抗氧化性和抗烧蚀性。由于在高温空气环境中薄膜涂层表面形成了致密的氧化层，它作为关键屏障有效地阻止了氧气的进入。该涂层的氧化层厚度异常薄，仅为8μm，同时在800℃空气暴露下对其抗氧化性进行了严格评估，证明其能提供至少10小时的持久保护。此外，在使用能产生高达1000℃温度的火焰喷枪进行烧蚀测试时，薄膜涂层的线性烧蚀速率仅为1.04μm/分钟。我们的分析表明，在薄膜涂层表面形成新的SiO时会发生BO的挥发。这种现象导致热量吸收，从而提高了薄膜传感器的抗烧蚀性能。结果表明，该薄膜传感器在涂层保护下表现出优异的抗氧化和抗烧蚀性能，在航空航天应用中具有巨大潜力。
