在190°C的缓慢烤下,CL-20/HMX共晶体的异热结构演变
Wentao Liang1, Xiaoyu Sun2, He Wang1
1Department of Physics, School of Physics Science, University of Science and Technology of China, Hefei, Anhui, 230026, China. liangwt@mail.ustc.edu.cn.
Physical chemistry chemical physics : PCCP
|May 31, 2023
概括
这项研究揭示了CL-20/HMX共晶爆炸物在190°C时如何分解. CL-20组件分离和分解,而HMX重新结晶,导致分解速度减慢和安全洞察力提高.
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:
- 晶爆炸物,如CL-20/HMX,提供高能量密度和低灵敏度.
- 了解它们的分解行为对于安全处理和应用至关重要.
- 之前的研究指出,在更快的加热速度下,CL-20/HMX共晶体的分解温度为235°C.
研究的目的:
- 为了研究190°C的CL-20/HMX共晶体的同热结构演变.
- 为了阐明在亚分解温度下CL-20/HMX共晶体的分解机制.
- 为了解CL-20/HMX共晶爆炸物的安全特性提供见解.
主要方法:
- 在190°C的温度下对CL-20/HMX共晶体进行异热烤制.
- 使用先进的表征技术 (隐含) 分析结构变化和分解途径.
- 监测气体产品的演变和晶相转换.
主要成果:
- CL-20的初始分解是通过与 (010) 平面的分离而发生的.
- 气体产品 (NO2,NO) 逃逸,形成微泡和洞.
- 剩余的HMX重新结晶为δ相HMX,导致体积收缩72%.
- 在长时间加热的 (010) 平面上形成状结构.
- 在长时间加热后观察到CL-20的完全分解和完全再结晶为δ-HMX.
- 与纯CL-20相比,CL-20和HMX之间的相互作用显著减缓了分解速度.
结论:
- 在190°C下,CL-20/HMX共晶体的分解涉及CL-20分解和HMX再结晶的复杂相互作用.
- 观察到的较慢的分解速度提高了这些高能材料在温度低于它们公认的分解点时的安全性.
- 这项研究加深了对共晶能量材料稳定性和安全性的理解.
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