无形/纳米晶体,轻量级,波波透明的化纳米带气凝用于隔热
Junheng Wang1, Laifei Cheng1, Fang Ye1
1Science and Technology on Thermostructural Composite Materials Laboratory, Northwestern Polytechnical University, Xi'an 710072, China.
ACS applied materials & interfaces
|September 28, 2023
概括
研究人员开发了一种新型的化 (BN) 纳米带气凝,用于高温飞机雷多. 这种轻质材料提供了出色的隔热和电磁波透明度,在极端条件下保护天线.
科学领域:
- 材料科学 材料科学 材料科学
- 航空航天工程 航空航天工程
- 纳米技术 纳米技术
背景情况:
- 现代飞机需要先进的材料来实现高速飞行,面对高达1800°C的极端温度.
- 现有的隔热系统在这些温度下,难以保持雷多姆内部的天线功能.
- 气凝以低密度和高孔隙性而闻名,在隔热应用中具有前景.
研究的目的:
- 为了合成和描述一种新的无形/纳米晶体化 (BN) 纳米带气凝.
- 为了评估其作为飞机雷多姆的高温,电磁波透明热绝缘体的潜力.
- 探索其作为耐火和机械能耗材料的性能.
主要方法:
- 无形/纳米晶体化 (BN) 纳米带气凝的合成.
- 热稳定性,密度,电磁波透明度和隔热性能的表征.
- 通过疲劳测试评估结构稳定性和能量损失系数.
主要成果:
- 合成的BN气凝是轻质的 (18mg/cm3).
- 它表现出优异的热稳定性 (1400°C无效,750°C空气) 和热绝缘性 (43mW/m·K) 在RT,73mW/m·K在600°C).
- 该材料表现出宽带波透明度 (介电常数1.03,损耗0.016在4-18 GHz) 和良好的结构稳定性.
结论:
- 新型BN纳米带气凝是飞机中高温电磁波透明隔热的非常合适的候选者.
- 它的耐火性和机械能耗性能提供了额外的好处.
- 这项研究为设计用于极端环境的先进功能绝缘材料提供了新的方法.
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