Li Yan, Yu Wen-Li, Huang Huang, Zhu Min, Wang Jin-Tao
Xi'an High-Tech Research Institute Xi'an 710025 China.
Naval University of Engineering Wuhan 430033 China.
RSC Adv. 2021 Nov 29;11(61):38383-38390. doi: 10.1039/d1ra06746j.
Using the molecular dynamics method based on the ReaxFF force field and combining it with the multi-scale shock technique, the physical and chemical change processes of CL-20/TNT co-crystals under shock loading were studied. Shock waves with velocities of 7, 8, 9 km s were applied to CL-20/TNT co-crystals along the , , and directions. The anisotropy brought by the co-crystal structure was analyzed. The results show that the temperature, stress, volume compressibility, decomposition rate, products, and the cluster of CL-20/TNT are strongly related to the direction of shock waves. With the same velocity, the shock wave along the direction can make the system more compressed, to obtain higher temperature and greater stress. When the velocities of shock waves are 7 km s and 8 km s, systems with a higher degree of compression have a higher degree of chemical reaction, the reactants decompose faster, and richer products are generated. When the shock wave velocity is 9 km s, the chemical reactions are more intense, and the differences between reactants and products due to anisotropy are small. The amounts, compositions, sizes, and mass ratios of the cluster are strongly anisotropic due to the special layered structure of the energetic co-crystal, and the evolutionary processes are closely related to the chemical reaction process. The research in this paper can provide certain support for the understanding of the shock response process of energetic co-crystals.
采用基于ReaxFF力场的分子动力学方法,并结合多尺度冲击技术,研究了CL-20/TNT共晶体在冲击载荷作用下的物理和化学变化过程。沿 、 、 方向对CL-20/TNT共晶体施加速度为7、8、9 km s的冲击波。分析了共晶体结构带来的各向异性。结果表明,CL-20/TNT的温度、应力、体积压缩率、分解速率、产物以及团簇与冲击波方向密切相关。在相同速度下,沿 方向的冲击波可使体系压缩程度更大,获得更高的温度和更大的应力。当冲击波速度为7 km s和8 km s时,压缩程度较高的体系化学反应程度较高,反应物分解更快,生成的产物更丰富。当冲击波速度为9 km s时,化学反应更剧烈,各向异性导致的反应物与产物之间的差异较小。由于含能共晶体特殊的层状结构,团簇的数量、组成、尺寸和质量比具有强烈的各向异性,其演化过程与化学反应过程密切相关。本文的研究可为理解含能共晶体的冲击响应过程提供一定的支持。