Chen Bowen, Ni Dewei, Bao Weichao, Liao Chunjing, Luo Wei, Song Erhong, Dong Shaoming
State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai, 201899, China.
Structural Ceramics and Composites Engineering Research Center, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai, 201899, China.
Adv Sci (Weinh). 2023 Dec;10(34):e2304254. doi: 10.1002/advs.202304254. Epub 2023 Oct 22.
Ultrahigh temperature ceramic matrix composites (UHTCMCs) are critical for the development of high Mach reusable hypersonic vehicles. Although various materials are utilized as the thermal components of hypersonic vehicles, it is still challenging to meet the ultrahigh temperature ablation-resistant and reusability. Herein, the Y O reinforced C /ZrB -SiC composites are designed, which demonstrates near-zero damage under long-term ablation at temperatures up to 2500 °C for ten cycles. Notably, the linear ablation rate of the composites (0.33 µm s ) is over 24 times better than that of the conventional C /C-ZrC at 2500 °C (8.0 µm s ). Moreover, the long-term multi-cycle ablation mechanisms of the composites are investigated with the assistance of DFT calculations. Especially, the size effect and the content of the Zr-based crystals in the oxide layer fundamentally affect the stability of the oxide layer and the ablation properties. The ideal component and structure of the oxide layer for multi-cycle ablation condition are put forward, which can be obtained by controlling the Y O /ZrB mole ratio and establishing Y-Si-O - t-Zr Y O core-shell nano structure. This work proposes a new strategy for improving the long-term multi-cycle ablation resistance of UHTCMCs.
超高温陶瓷基复合材料（UHTCMCs）对于高马赫数可重复使用高超音速飞行器的发展至关重要。尽管各种材料被用作高超音速飞行器的热部件，但要满足超高温抗烧蚀性和可重复使用性仍然具有挑战性。在此，设计了Y₂O₃增强的C/ZrB₂-SiC复合材料，该复合材料在高达2500℃的温度下进行十次循环的长期烧蚀后显示出近零损伤。值得注意的是，该复合材料在2500℃时的线性烧蚀速率（0.33 µm/s）比传统的C/C-ZrC在2500℃时的线性烧蚀速率（8.0 µm/s）好24倍以上。此外，借助密度泛函理论（DFT）计算研究了该复合材料的长期多循环烧蚀机理。特别是，氧化层中Zr基晶体的尺寸效应和含量从根本上影响氧化层的稳定性和烧蚀性能。提出了多循环烧蚀条件下氧化层的理想组成和结构，可通过控制Y₂O₃/ZrB₂的摩尔比并建立Y-Si-O-t-Zr-Y₂O₃核壳纳米结构来实现。这项工作为提高UHTCMCs的长期多循环抗烧蚀性提出了一种新策略。
