化学学报 ›› 2007, Vol. 65 ›› Issue (17): 1746-1750. 上一篇    下一篇

研究论文

HMX晶体和HMX/F2311 PBXs力学性能的MD模拟研究

肖继军*,1, 黄辉2, 李金山2, 张航1, 朱伟1, 肖鹤鸣*,1   

  1. (1南京理工大学化工学院 分子与材料计算研究所 南京 210094)
    (2中国工程物理研究院 化工材料研究所 绵阳 621900)
  • 投稿日期:2007-02-01 修回日期:2007-03-21 发布日期:2007-09-14
  • 通讯作者: 肖继军, 肖鹤鸣

MD Simulation Study on the Mechanical Properties of HMX Crystals and HMX/F2311 PBXs

XIAO Ji-Jun*,1; HUANG Hui2; LI Jin-Shan2; ZHANG Hang1; ZHU Wei1; XIAO He-Ming*,1   

  1. (1 Molecule and Material Computation Institution, School of Chemical Engineering, Nanjing University of Science and Technology, Nanjing 210094)
    (2 Institute of Chemical Materi-als, China Academy of Engineering Physics, Mianyang 621900)
  • Received:2007-02-01 Revised:2007-03-21 Published:2007-09-14
  • Contact: XIAO Ji-Jun, XIAO He-Ming

用分子动力学方法, 在295 K NVT系综和COMPASS力场下, 对环四甲撑四硝胺(HMX)晶体和F2311沿HMX (001), (010)和(100)晶面所构成PBXs模型的力学性能进行模拟研究. 结果表明, 加入F2311降低了HMX的刚性, 增强了它的延展性. 在HMX (100)面上添加F2311对提高体系的延展性较显著. 为考察温度对力学性能的影响及其机理, 在245~445 K范围完成对HMX (100)/F2311 PBX的MD模拟. 力学分析表明, 随温度增加HMX (100)/F2311的延展性呈抛物线变化规律, 归因于F2311分子链的运动及其构象随温度的变化.

关键词: 环四甲撑四硝胺(HMX), 高聚物粘结炸药(PBXs), 分子动力学, 力学性能

Molecular simulation was applied to investigate the mechanical properties of β-octahydro- 1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) crystals and the polymer-bonded explosives (PBXs) which were made from the HMX as a base and F2311 as a binder, in NVT ensemble using COM-PASS force field. The PBXs’ model was constituted by putting F2311 on crystal (001), (010) and (100) surface respectively. At 295 K, the elastic constants and the effective moduli were calculated by statistic analysis mode. Cauchy pressure C12-C44 was also calculated. It was shown that the rigidity was weakened and the ductibility was improved by adding small amount of F2311, and the ductibility improvement was most obvious when F2311 was put on HMX (100) crystal surface. From the temperature 245 to 445 K with the increase step of 50 K, pure HMX crystals and HMX (100)\F2311 PBX were allowed to dynamically evolve. It is indi-cated that the mechanical properties of pure HMX crystals are unchanged because thermal effect of the volume is constrained by NVT ensemble. However, the ductibility of HMX (100)\F2311 PBX changes according to a parabola with increasing temperature due to the improvement of F2311 chain moving ability and the simultaneous increment of high energy conformation ratio in this molecular chain, i.e., the increment of the molecular chain rigidity.

Key words: octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine, polymer-bonded explosive, molecular dynamics, mechanical property