颗粒层次结构对密度,燃烧效率和点火延迟的影响
1State Key Laboratory of Precision Blasting, Jianghan University, Wuhan 430056, China.
Materials (Basel, Switzerland)
|September 14, 2024
概括
研究人员开发了新的纳米粒子 (nAl) 和微米粒子 (mAl) 复合材料,用于增强爆炸性配方. 与传统材料相比,这些mAl@nAl复合材料显示出更高的燃烧效率和性能.
科学领域:
- 材料科学 材料科学 材料科学
- 纳米技术 纳米技术
- 能量材料 能量材料
背景情况:
- 纳米粒子 (nAl) 在爆炸性配方中具有高反应性但低密度.
- 微米颗粒 (mAl) 的密度较高,但反应性较低.
- 低密度的nAl配方显著降低了能量释放性能.
研究的目的:
- 在现场开发集成的微米 (mAl) 和纳米粒子 (nAl) 复合材料 (mAl@nAl).
- 评估这些新型复合材料的性能,用于增强爆炸性配方.
- 为了利用mAl和nAl颗粒的好处.
主要方法:
- mAl@nAl复合材料是通过线的现场电爆制成的.
- 使用扫描电子显微镜 (SEM) 进行形态的表征,密度的密度测量,以及特定表面积 (SSA) 的Brunauer-Emmett-Teller (BET).
- 燃烧性能通过在不同条件下 (零氧平衡,恒温) 进行恒定体积燃烧试验来评估.
主要成果:
- SEM证实了在mAl表面上均的nAl附着性.
- 在制备过程中增加的电压导致复合材料直径和密度下降,但增加了SSA (高达12.1192 m2/g).
- 与物理分级对应物相比,mAl@nAl复合材料的燃烧效率 (8.26%),加压率,峰值压力和燃烧温度 (1.15-1.45倍) 较高.
结论:
- 在现场合成mAl@nAl复合材料有效地整合了两种颗粒大小的优势.
- 准备好的复合材料达到高密度 (高达1.13g/cm3) 和显著改善的燃烧特性.
- 这些发现为开发具有卓越性能的先进能量材料提供了有希望的方法.
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