Cheng Yehong, An Yumin, Liu Yaxiong, Wei Qiang, Han Wenbo, Zhang Xinghong, Zhou Peng, Wei Chuncheng, Hu Ning
School of Mechanical Engineering, Hebei University of Technology, Tianjin 300401, P. R. China.
Research Institute for Structure Technology of Advanced Equipment, Hebei University of Technology, Tianjin 300401, P. R. China.
ACS Appl Mater Interfaces. 2020 Jul 22;12(29):33246-33255. doi: 10.1021/acsami.0c08206. Epub 2020 Jul 8.
The intrinsic brittleness and poor damage tolerance of ultrahigh-temperature ceramics are the key obstacles to their engineering applications as nonablative thermal protection materials. Biomimetic layered or "brick-and-mortar" hybrid composites composed of alternative strong/weak interfaces exhibit excellent strength and high toughness; however, the commonly used interfacial materials are weak and have poor thermal stability and ablation resistance, which strictly limit their use in high-temperature and oxidative environments. In this work, ZrB-based "brick-and-mortar" hybrid ceramics were constructed with a hierarchical biomimetic design to improve the fracture resistance and damage tolerance. ZrB-20vol %SiC ceramics containing 30 vol % reduced graphene oxide nanosheets were used as the weak interface to increase crack growth resistance without destroying the excellent ablation resistance. Finally, the ZrB-based "brick-and-mortar" composites achieve the synergy of superior damage tolerance and ablation resistance.
超高温陶瓷固有的脆性和较差的损伤容限是其作为非烧蚀热防护材料在工程应用中的关键障碍。由交替的强/弱界面组成的仿生层状或“砖-灰浆”混合复合材料表现出优异的强度和高韧性；然而，常用的界面材料强度较弱，热稳定性和抗烧蚀性较差，这严格限制了它们在高温和氧化环境中的应用。在这项工作中，采用分级仿生设计构建了ZrB基“砖-灰浆”混合陶瓷，以提高其抗断裂性和损伤容限。含有30 vol%还原氧化石墨烯纳米片的ZrB-20vol%SiC陶瓷被用作弱界面，以增加抗裂纹扩展能力，同时不破坏优异的抗烧蚀性。最终，ZrB基“砖-灰浆”复合材料实现了优异的损伤容限和抗烧蚀性的协同作用。
