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用于电力推进的石墨/h-BN双材料的评价
Celia S Chari1, Richard R Hofer2, Bryan W McEnerney2,3
1California Institute of Technology, Pasadena, CA 91106 USA.
Journal of electric propulsion
|May 12, 2025
概括
本研究评估了用于霍尔效应推进器的新型石墨/六角化 (h-BN) 双材料. 蒸汽相合成双材料的性能与散装h-BN相比,表明了先进航天器推进的潜力.
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
- 等离子体物理学的物理学
背景情况:
- 霍尔效应推进器需要坚固的介电壁材料来承受恶劣的等离子体环境.
- 当前最先进的材料,如散装六角化 (h-BN),在制造或热性能方面存在局限性.
- 双材料提供了一个潜在的解决方案,通过将不同材料的理想性质结合起来.
研究的目的:
- 评估用于霍尔效应推进器应用的创新石墨/h-BN双材料的性能.
- 通过液相与蒸汽相碳热反应合成的双物质的性能进行比较.
- 为了评估双材料的耐侵蚀性与最先进的散装h-BN.比较.
主要方法:
- 在中使用B2O3的液相和蒸汽相碳热反应合成石墨/h-BN双材料.
- 材料性质的表征,包括介电性行为,排放性和耐热冲击性.
- 在模拟的霍尔效应推进器环境中进行性能测试,用离子测量侵蚀率.
主要成果:
- 石墨/h-BN 双材料展示了h-BN 的介电性质和石墨的热阻的组合.
- 与液相合成的双材料相比,蒸汽相合成的双材料表现出更高的性能.
- 蒸汽阶段培养的h-BN层的侵蚀率与散装的h-BN相似,喷率为0.021 mm3/C,电压为300 V.
结论:
- 石墨/h-BN双材料,特别是通过蒸汽相方法合成的双材料,是霍尔效应推进器应用的有希望的候选材料.
- 开发的双材料提供了理想的表面和散装性能的平衡.
- 进一步研究优化合成和长期性能是有必要的.
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