RDX和HMX晶体压制方程的对比研究

分别选取经过不同重结晶工艺处理的RDX和HMX晶体和一种工业级原料颗粒样品进行准静态压制实验，由实验应力／位移曲线获得压制曲线，采用Kawakita和Heckel方程对压制曲线进行拟合。结果表明，拟合所得的常数具有模量倒数量纲，能区分重结晶和原料样品，用作含能晶体品质评价的定量参数。比较两个压制方程的模拟情况，对RDX颗粒两个方程均拟合得很好，而对HMX颗粒存在一定的误差，尤其是Heckel方程误差较大。选取压制过程的形变破碎阶段的数据所得结果其区分度有明显提高，同时两个方程的拟合情况均得到明显改善。对于含能材料颗粒，Kawakita方程更合适。     

RDX和HMX晶体压制方程的对比研究

分别选取经过不同重结晶工艺处理的RDX和HMX晶体和一种工业级原料颗粒样品进行准静态压制实验,由实验应力/位移曲线获得压制曲线,采用Kawakita和Heckel方程对压制曲线进行拟合.结果表明,拟合所得的常数具有模量倒数量纲,能区分重结晶和原料样品,用作含能晶体品质评价的定量参数.比较两个压制方程的模拟情况,对RDX颗粒两个方程均拟合得很好,而对HMX颗粒存在一定的误差,尤其是Heckel方程误差较大.选取压制过程的形变破碎阶段的数据所得结果其区分度有明显提高,同时两个方程的拟合情况均得到明显改善.对于含能材料颗粒,Kawakita方程更合适.     

HMX基PBX炸药热损伤的数值计算与实验研究

基于二维平面轴对称模型,采用有限元软件ANSYS,对HMX基PBX在温度冲击载荷作用下的温度场和应力场进行数值计算,为了验证有限元模拟分析的可靠性,对HMX基PBX药柱进行了温度冲击试验,用热电偶和声发射技术测量药柱表面的温度及热损伤。数值计算结果表明,在降温阶段,药柱侧面中部受到较大轴向拉应力作用而产生热损伤。实验结果与计算结果吻合较好,说明HMX基PBX热损伤破坏方式为拉应力破坏,抗拉强度可以较好地反映材料的耐热损伤能力。     

高品质压装HMX基PBX炸药的冲击波感度

为改善HMX基PBX的安全性能,通过隔板试验研究了高品质HMX的粒度对压装PBX炸药冲击波起爆性能的影响.结果表明·对于相对密度较高(98.5％TMD)的压装HMX基PBX,与普通品质(平均粒径30μm)相比,使用高品质HMX(20 μm)后PBX的冲击波感度下降了7％,当高品质HMX的粒度增至150μm后,其冲击波起...     

压制过程中PBX炸药颗粒的破碎及损伤

用扫描电镜及激光粒度仪研究了PBX炸药在不同压制条件下的微观结构变化及粒度分布。结果表明,随着成型试件密度的增加,晶体的破碎、损伤情况加重;成型试件中HM X的平均粒径随着压力的增加而减小(压制前的33.05μm到250M Pa压制后的16.92μm);在相同压力条件下,热压(70℃)制品的密度更高,但晶体的破碎却更小,热压(70℃)制品中HM X的平均粒径要大于冷压(25℃)制品中HM X的平均粒径。     

添加剂对HMX重结晶晶体形貌的影响

通过模拟计算与试验相结合的方法,研究了添加剂乙酰胺、丙烯酰胺、乙胺水溶液对重结晶HMX晶体形貌控制的影响.结果表明,3种添加剂对HMX重结晶晶体形貌影响的大小顺序为:乙酰胺＞丙烯酰胺＞乙胺,乙酰胺使晶体偏离球形化,丙烯酰胺具有使晶体向着球形化发展的趋势,由于乙胺与HMX晶面的附着能较小,乙胺对HMX重结晶晶体形貌改变不...     

HMX塑料粘结炸药的粘接研究

测试了水和甲酰胺对 HMX塑料粘结炸药 (PBX)药柱表面的接触角 ,它们的接触角分别为 82°和 32°;计算了 HMX药柱的表面能为 91 m N/ m,这表明 HMX塑料粘结药柱表面为低能表面。比较了几种结构胶粘剂粘接药柱的剪切强度 ,使用环氧胶时为 7.6MPa。试验发现胶粘剂种类、厚度对 HMX塑料粘结剂药柱爆速的影响较小     

含不同粒度HMX的PBX(HMX)在AP促进下的热分解及激光点火性能

为探究主体炸药HMX的粒度对PBX(HMX)/AP复合含能材料的热分解和激光点火性能的影响,通过溶剂-非溶剂法对原料HMX和AP进行重结晶并筛分得到不同粒径分布的HMX_R和细粒度AP_R(5～20μm),进而制备含不同HMX粒度的PBX(HMX)/AP,对所得晶体和复合物分别进行SEM、DSC、DSC-IR及热分解动力学和1064nm激光点火测试。结果表明,HMX_R和AP_R的热分解表观活化能E_a和热爆炸临界温度T_b随着晶体粒度减小而减小;PBX(HMX)/AP中,HMX_RC的粒径范围为30～140μm、d₅₀为68μm、按HMX与AP零氧平衡配比的PBX(HMX_RC)/AP热性能最优,其热分解表观活化能E_a为212.78kJ/mol,比HMX_RC降低约274.44kJ/mol;其热爆炸临界温度为197.45℃,比HMX_RC降低约...     

原位聚合包覆HMX的研究

为探索制备PBX的新方法,利用原位聚合反应,直接在HMX表面包覆一层热塑性高聚物,获得了分别以端羟基聚丁二烯(HTPB),聚叠氮缩水甘油醚(GAP)、3,3-双(叠氮甲基)环氧丁烷-四氢呋喃共聚醚(BAMO-THF)3种黏结剂包覆的PBX.通过光学显微镜、显微-红外、光电子能谱(XPS)、元素分析和机械感度测定对包覆效果进行表征.结果表明,HMX表面较均匀地包覆上了一层聚合物,黏结剂的质量分数约为4%～5%,包覆HTPB的HMX机械感度明显下降,而包覆GAP和BAMO-THF的HMX机械感度略有降低.     

HMX晶体形貌的计算模拟

利用Material Studio中Morphology模块所含的BFDH、Growth Morphology和Equilibrium Morphology 3种方法计算了HMX的晶体形态和结晶习性;研究了重要晶面的结构、晶体的生长习性和晶面结构与晶形控制剂的关系.结果表明,Growth Morphology和Equilibrium Morphology方法的计算结果与实际比较吻合.     

高聚物黏结炸药的压制成型性

为了获得高聚物黏结炸药(PBX)压制成型的基本规律,对TATB基PBX进行等静压压制试验,研究了PBX压制过程中的一些力学行为,通过对力学和物理性能测试及SEM分析,得到PBX的微显结构和在成型过程中的性能参数变化规律。结果表明,在PBX颗粒压制成型过程中,成型件的密度、泊松比、压缩模量和压缩强度与压力呈对数函数关系。成型件泊松比、压缩强度与压缩模量随成型密度的增加快速增大。延长保压时间可以有效提高压实密度,使成型效果更好。     

Research on the Size of Defects inside RDX/HMX Crystal and Shock Sensitivity

Intragranular defects inside RDX/HMX were studied by optical microscopy with matching refractive (OMS), sink‐float method (SFM), and micro‐focus CT (μCT) techniques. OMS results revealed the phenomenon that RDX/HMX had more defects and cracks than RS‐RDX/RS‐HMX. μCT results indicated that RDX/HMX had more defects with larger volume than RS‐RDX/RS‐HMX. The gap test showed that critical shock pressure/gap thickness was 6.4 GPa/19.4 mm for PBX based on RDX, while they were 7.5 GPa/17.5 mm and 8.6 GPa/16.2 mm for PBX based on M‐RDX and RS‐RDX, respectively. Meanwhile, an analysis of the relationship between defects inside RDX/HMX crystal and shock sensitivity was made. Finally, the shock pressure response under impact loading was investigated by discrete element method.     

超临界CO2GAS沉析HMX制细过程的影响因素

研究了超临界CO2GAS沉析丙酮溶液中HMX的过程压力、温度、溶液初始浓度和溶液的膨胀速度及影响晶体粒度的因素。结果表明，压力增加，沉析颗粒的平均粒度减小；温度控制沉析晶体的晶型，对颗粒度的影响相对较小，温度增加，沉析平均粒度略有增加；溶液初始浓度对平均粒度的影响相对较大，膨胀速度亦是影响粒度及其分布的一个因素。快速膨胀溶液．并使过饱和度足够大，使过饱和度主要消耗在成核上，可得到颗粒小、分布窄的HMX颗粒。     

Fabrication and Properties of Insensitive CNT/HMX Energetic Nanocomposites as Ignition Ingredients

Cyclotetramethylene tetranitramine (HMX)‐coated carbon nanotube (CNT) nanocomposites with uniform structures were prepared using the recrystallization method. Characterization (SEM, TEM, XRD, BET, etc.) was performed to determine the micromorphology, crystal structure, and specific surface area. The energetic particles were homogeneously distributed on the surfaces of the CNTs, and the maximum thickness of the coating layer was approximately 120 nm, whereas the average crystal size was less than 50 nm. The test results of the thermal behavior showed that the thermal decomposition temperature decreased as the CNT content increased, and the maximum thermal conductivity was approximately 27.3 times higher than that of pure HMX. The sensitivities of the CNT/HMX nanocomposites to impact, friction, and shock were maximally reduced by 73 %, 29 %, and 74 % compared with those of pure HMX, respectively, which demonstrated a significant safety improvement. In the CNT/HMX nanocomposites, aluminum and ferric oxide were used to fabricate a new type of ignition composition. Based on comparative studies, the results showed that the ignition composition was porous and that its particles were more evenly distributed compared with the conventional counterparts. The thermal conductivity was improved by 21 %. The impact and friction sensitivities were also maximally reduced by 21 % and 27 %, respectively. The combustion heat was also increased by 9 % compared with that of a mixture of the same components.     

Study of Thermal Reactivity and Kinetics of HMX and Its PBX by Different Methods

Vacuum Stability Test (VST) was used to determine the thermal behavior and kinetic parameters of 1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) and its mixture with hydroxyl-terminated polybutadiene (HTPB) as a binder coded as HMX/HTPB.Model fitting and isoconversional method were applied to determine the kinetic parameters based on VST results.For comparison,non-isothermal thermogravimetry analysis data (TGA) was also used to calculate the kinetic parameters by using Kissinger,OFW (Ozawa,Flynn,and Wall) and KAS (Kissinger-Akahira-Sunose) methods.Advanced Kinetics and Technology Solution (AKTS) software was also used to determine the decomposition kinetics of the studied samples.Differential Scanning Calorimetry (DSC) was employed to determine the decomposition heat flow properties of the studied samples.Results show that the activation energies obtained using VST results is 360.1kJ/ mol for pure HMX and 186.9kJ /mol for HMX/HTPB.The activation energies obtained by the three different methods using TGA results are in the range of 360-368kJ/mol for pure HMX and 190-206kJ/mol for HMX/HTPB.It is concluded that values of kinetic parameters obtained by VST are close to that obtained by the different techniques using TG/DTG results.The onset decomposition peak of HMX/HTPB is lower than that of HMX where the HTPB binder has negative effect on the thermal stability of HMX.The results of all the applied techniques prove that HMX/HTPB has lower activation energy and heat release than the pure HMX.HTPB polymeric matrix has negative effect on the kinetic parameters of HMX.     

超细ANPyO/HMX混晶炸药的制备与性能

为提高超细ANPyO/HMX的能量输出,采用溶剂/非溶剂法和水悬浮法制备了超细ANPyO/HMX混晶炸药。用SEM、XRD、红外光谱对其结构进行表征,并测试了其比表面积、真空安定性、撞击感度、冲击波感度、爆速和飞片起爆感度。结果表明,XRD和红外光谱特征峰的位移现象说明超细混晶炸药中ANPyO分子的氨基与HMX分子的硝基形成了分子间氢键;ANPyO/HMX混晶炸药(ANPyO与HMX质量比为70∶30)撞击感度为138cm,真空安定性为1.72mL/g(200℃)和4.50mL/g(250℃)。装药密度为1.84g/cm3时,混晶炸药冲击波感度为7.1mm,爆速为8 080m/s,最低起爆电压为2.91kV,是一种感度适中、易于被短脉冲起爆、能量输出高的超细混晶炸药。     

冲击波作用下HMX晶体的细观响应

用折光匹配显微技术(OMS)、表观密度浮沉法(SFM)、微聚焦CT扫描表征了HMX晶体内部缺陷尺寸、数量。结果表明,D-HMX较普通HMX含有较大尺寸内部缺陷的数量较少,普通HMX含有大量10-5mm3以上缺陷,普通HMX和D-HMX晶体均含有大量10-6mm3量级以下缺陷。利用基于细观结构的冲击波效应数值模拟方法,研究了晶体内部缺陷尺寸对其冲击波温升效应的影响。模拟结果表明,在低压条件下,等效半径为20~40μm的内部缺陷在冲击波加载下温升较高,等效半径为10~15μm的内部缺陷温升相对较低。当冲击波压力增高至5.8GPa,等效半径为10μm内部孔洞在冲击波作用下温升可达到850K以上,两者的冲击波感度接近。