奥克托今/3-硝基-1，2，4-三唑-5-酮共晶炸药晶体缺陷的分子动力学研究

为研究晶体缺陷对奥克托今（HMX）/3-硝基-1,2,4-三唑-5-酮（NTO）共晶炸药稳定性、感度、爆轰性能与力学性能的影响，分别建立了“完美”型与含有掺杂、空位与位错缺陷的共晶炸药模型。采用分子动力学方法，预测了“完美”型与缺陷模型的性能，得到了不同模型的结合能、引发键键长分布、键连双原子作用能、内聚能密度、爆轰参数与力学性能参数，并进行了比较。结果表明：由于晶体缺陷的影响，造成炸药结合能减小，稳定性变差；缺陷晶体的引发键最大键长增大，键连双原子作用能与内聚能密度减小，炸药感度升高，安全性减弱；缺陷晶体的密度、爆速与爆压减小，能量密度与威力降低；与“完美”型晶体相比，缺陷晶体的拉伸模量、体积模量与剪切模量减小，柯西压力增大，炸药刚性与硬度减弱，柔性与延展性增强。

Molecular Dynamics Investigation on Crystal Defect of HMX/NTO Cocrystal Explosive

The “perfect” and defective cocrystal models with adulteration, vacancy and dislocation are established to investigate the influence of crystal defect on stability, sensitivity, detonation performance and mechanical property of octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX)/ 3-nitro-1,2,4-triazol-5-one (NTO) cocrystal explosive. Molecular dynamics method is applied to predict the properties of the proposed crystal models. The binding energy, bond length distribution of trigger bond, interaction energy of trigger bond, cohesive energy density, detonation parameters and mechanical properties were obtained and compared. The results show that the binding energy of explosive is declined and its stability is weakened due to the influence of crystal defect. The maximum trigger bond length of defective crystal model is increased, while the interaction energy of trigger bond and the cohesive energy density are decreased, meaning that the sensitivity of explosive is increased and its safety is worsened. The density, detonation velocity and detonation pressure of defective crystal model are declined, indicating that the energy density and power are lessened. Compared with the “perfect” crystal model, the tensile modulus, bulk modulus and shear modulus of defective crystal model are decreasaed, and Cauchy pressure is increased, namely, the rigidity and stiffness are declined and the plastic property and ductility are increased.