Efficient fabrication of light Cf/SiHfBOC composites with excellent thermal shock resistance and ultra-high-temperature ablation up to 1800 °C
Autor: | Yang Lyu, Zhihong Han, Guangdong Zhao, Yuan Cheng, Shanbao Zhou, Xinghong Zhang, Guiqing Chen, Wenbo Han |
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Jazyk: | angličtina |
Rok vydání: | 2023 |
Předmět: | |
Zdroj: | Journal of Advanced Ceramics, Vol 12, Iss 11, Pp 2062-2074 (2023) |
Druh dokumentu: | article |
ISSN: | 2226-4108 2227-8508 |
DOI: | 10.26599/JAC.2023.9220808 |
Popis: | In this paper, a high-yield Hf-modified SiHfBOC ceramic precursor was developed, and a high-pressure assisted impregnation pyrolysis method was proposed to achieve the preparation of 3D PyC–Cf/SiHfBOC composites. This high-pressure assisted impregnation method significantly improves impregnation filling effect of the precursor in and between fiber bundles compared to dozens of traditional impregnation cycles. After undergoing just 9 precursor infiltration pyrolysis (PIP) cycles, the composites achieved relative density of approximately 90% and density of 1.64 g/cm3. The critical temperature difference of the 3D PyC–Cf/SiHfBOC composites after the shock of room temperature (RT)–1000 ℃ is as high as 650 ℃, which is twice that of traditional ceramic materials, showing good thermal shock resistance. Under the effect of Hf modification, a dense HfO2–SiO2 oxide layer (thickness of 93 μm) was formed in situ on the surface of the 3D PyC–Cf/SiHfBOC composites, effectively preventing further erosion of the composite matrix by high-temperature oxidation gas. Even in the ultra-high-temperature oxygen-containing environment at 1800 ℃, it still exhibits an excellent non-ablative result (with a linear ablation rate of 0.83×10−4 mm/s). This work not only enriches the basic research on lightweight ultra-high-temperature ceramic composites converted from Hf ceramic precursors, but also provides strong technical support for their applications in ultra-high-temperature non-ablative thermal protection materials for high-speed aircraft. |
Databáze: | Directory of Open Access Journals |
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