纳米热反应性的突然转变:加载密度,微观结构和成分的作用
Chengbo Ru1,2, Yanchun Zhang1,2, Aoyang Yu1,2
1College of Forensic Science, Criminal Investigation Police University of China, Shenyang 110035, China.
Molecules (Basel, Switzerland)
|October 29, 2025
概括
基于纳米热的混合能量材料 (THEM) 的电荷密度增加会影响反应动力学. 较高的密度会降低孔隙性和传热量,降低燃烧效率和加压率,但Bi2O3-THEM显示持续的反应性.
科学领域:
- 材料科学 材料科学 材料科学
- 化学工程是化学工程的重要组成部分.
- 能量材料 能量材料
背景情况:
- 纳米热是微启动器和火器的重要动力来源.
- 电荷密度在有限系统中显著影响能量储存和反应动力学.
研究的目的:
- 研究基于纳米热的混合动力能量材料 (THEMs) 的燃烧和加压特性.
- 探索不同金属氧化物,能量添加剂和负载密度对THEM性能的影响.
主要方法:
- 用不同的金属氧化物 (Fe2O3,CuO,Bi2O3) 和添加剂 (NC,HMX,AP,CL-20) 系统测试THEM的燃烧和加压.
- 分析各种负载密度的THEMs,关联透度,热传递和反应动力学.
主要成果:
- 增加的负载密度降低了孔隙性和对流传热传递效率.
- 超过临界密度导致峰值压力下降,压缩率大大降低,燃烧持续时间延长.
- 对于Al/CuO/NC/CL-20复合材料的临界密度为37.943.9%TMD.
- 在高负载密度下的反应顺序:AP > HMX ≈ CL-20 > NC.
- 由于低点火温度和高气产,Bi2O3-THEMs保持高反应率,高达59.7%的TMD.
结论:
- 负载密度通过改变微观结构和热量/质量转移,极大地影响纳米热的燃烧和加压.
- 金属氧化物和能量添加剂的选择显著影响THEM的性能,特别是在高密度下.
- 基于Bi2O3的THEM提供卓越的高密度性能,为设计量身定制的能量材料提供了洞察力.
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