DNTF／RDX-CMDB推进剂低温力学性能

摘要

用单轴抗拉实验、动态力学分析仪和简支梁抗冲实验研究了不同3，4-二硝基呋咱基氧化呋咱（ DNTF）/ RDX 配比对DNTF/RDX改性双基（ CMDB）推进剂（ DNTF/RDX-CMDB，DFR推进剂）力学性能的影响。获得了-40℃下 DFR 推进剂的抗拉强度（σm ）、断裂延伸率（εm ）及抗冲强度（ aK ）。根据“时间-温度”等效原理的 WLF方程获得了 DFR推进剂β松弛阶段的动态特征量黏弹系数（Cg1）。分析了组分含量对各力学性能的影响和σm、εm 的变化规律。结果表明：低温下的σm、εm 和 aK 均与增塑剂含量间存在相关性。增塑剂含量减小，粘弹系数增加，NC分子侧基的“自由体积”下降，导致抗拉强度、断裂延伸率等力学性能降低。%Influence of different ratios of 1,3,5-trinitrohexahydrotriazine(RDX)to 3,4-bisnitrofurazan-furoxan(DNTF)on the me-chanical properties of DNTF/RDX composite modified double-base( CMDB)propellant( DNTF/RDX-CMDB,DFR propellant) was studied by uniaxial tensile test,charpy impact test and dynamic mechanical analyzer. The tensile strength(σm ),elongation at the maximum stress(εm )and impact strength( aK )of DFR propellant at -40 ℃ were obtained. The dynamical characteristics (viscoelastic coefficients Cg1)of β-relaxation was acquired by WLF equation according to the“Time-Temperature”equivalence principle. The effect of plasticizer content on the various mechanical properties and change rule of σm and εm were analyzed, showing that a good correlation between σm ,εm ,aK at low temperature and plasticizer content. The plasticizer content reducing, Cg1 increasing,“free volume of side group of NC molecule”decreasing make the mechanical performances(σm and εm )worsen.