中文摘要：

为研究固体推进剂的感度、热膨胀和力学性能，设计了不同配比、不同温度下的多组分高能模型体系进行分子动力学（MD）模拟。用其中易爆燃组分引发键的最大键长（Lmax ）判别安全性，结果表明，在4种不同配比的五组分混合体系中，当质量比（PEG /NG /BTTN）∶ AP ∶ HMX ＝2．5∶3．5∶2．3时，各引发键（O-N 和 N-N）的最大键长均为最大，预示该体系的安全性相对较差；（PEG /NG /BTTN）/AP /HMX /Al 六组分混合体系中各 Lmax值均随温度升高而单调递增，与感度随温度升高的实验事实一致。表明对复杂多组分体系热和撞击感度的相对大小，亦可用 Lmax判别。基于六组分体系的 MD 模拟结果，预估了该体系在不同温度下的热膨胀系数，并用静态力学分析求得其弹性力学性能，该体系的柯西压为正值，其延展性较好。

英文摘要：

Molecular dynamics（MD）simulation was employed to investigate safety performance（sensitivity）,thermal expansion and mechanical properties of solid propellant. The models of high energy multi-component systems with different sets of proportion were studied at different temperatures. It is found that the maximum bond lengths（L max ）of both O-N and N-N trigger bonds in the five-component system with the mass ratio of（PEG /NG /BTTN）∶ AP ∶ HMX =2. 5 ∶ 3. 5 ∶ 2. 3 are the longest among the four sets of the systems. Results show that the safety of the system having this proportion is relatively low. The L max of each deflagrating component in the six-component system（PEG /NG /BTTN）/AP /HMX /Al increases monotonously with the increasing temperature, which agrees with the experimental fact that energy materials become more sensitive as the temperature increases. It is suggested that structure parameter Lmax can also be used as a theoretical criterion of thermal or impact sensitivity to predict the relative safety of multi-component complicated systems. Based on the simulation results for the six-component system,thermal expansion coeffi-cients at different temperatures are calculated and mechanical properties are obtained with the static method.