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RDX晶体特性对冲击感度的影响规律 总被引:2,自引:3,他引:2
采用标准隔板和落锤撞击试验方法分别研究了RDX的晶体内部空隙(用晶体表观密度表征)、颗粒度和形貌对包括冲击波感度和撞击感度在内的冲击感度的影响规律。冲击波感度测试采用隔板试验,药柱配方为RDX/食用油(质量比为76/24),药柱采用液体填充方式制备。隔板试验研究表明:随着RDX晶体表观密度在1.7961~1.7983 g.cm-3范围内增加,炸药配方的冲击波感度降低,隔板厚度从14 mm降到12.2 mm,晶体表观密度与隔板厚度基本成线性关系;当晶体表观密度为1.7976 g.cm-3时,在50~600μm粒度范围内,随着颗粒度的增加,RD X炸药配方的冲击波感度降低,隔板厚度从13.5 mm降到12.3 mm;当晶体表观密度和颗粒度相近时,晶体颗粒的外观形貌对炸药冲击波感度影响不大。落锤撞击试验表明:RD X颗粒度对撞击感度影响较大,当平均颗粒直径在16.7~337.9μm范围时,随着粒径的增加,特性落高从75 cm降到35.8 cm,颗粒越大撞击感度越高;当颗粒度相近时,在1.7961~1.7983 g.cm-3范围内,RDX晶体表观密度对撞击感度几乎无影响。 相似文献
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基于RDX单晶可用于其起爆机理和力学响应机制等基础研究,采用丙酮溶剂缓慢挥发法分别在室温和恒温条件下培养RDX单晶。结果表明:两种方法都可以得到厘米级的RDX单晶,在恒温条件下培养的RDX单晶质地较硬、密度较高;同时,对实验中出现的多种晶体缺陷进行了分析;应用X-射线单晶衍射法测定了恒温条件下培养的RDX晶体结构,表明其晶体属于正交晶系,空间群为Pbca,所得晶体学参数为:a=11.471(3)?,b=10.611(2)?, c=13.146(3)?,α=β=γ=90°,体积V=1600.1(6)nm3,Z=8,密度D=1.844g/cm3,F(000)=912。最终偏差因子R1=0.0309。 相似文献
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Inclusion entrapped inside the crystals prepared in the cooling crystallization of cyclotrimethylenetrinitramine (RDX) from solution was studied. Effect of supersaturation on the inclusion formation was also studied in crystallization using solvents. Solvents such as acetone (AC), cyclohexanone (CH), dimethylsulfoxide (DMSO), N‐methylpyrrolidone (NMP), γ‐butyrolactone (BL), and their mixtures with water were investigated. The quantitative amount of inclusions entrapped in the RDX crystallized in various solvents was related to the supersaturation. The inclusion fraction in the crystals was affected by the supersaturation and the solvent. In order to decrease the inclusion fraction, in the low supersaturation, AC and CH were recommended, while in high supersaturation, NMP and DMSO were desirable. Eventually the solvent effect on the inclusion was grasped by considering the supersaturation effect. 相似文献
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Christian Spyckerelle Genevive Eck Per Sjberg Anna‐Maria Amnus 《Propellants, Explosives, Pyrotechnics》2008,33(1):14-19
In recent years much interest has been generated in a quality of reduced sensitivity RDX (RS‐RDX), like I‐RDX® which, when incorporated in cast cure and even pressable plastic bonded explosives (PBX compositions), can confer reduced shock sensitivity as measured through gap test. At crystal level, lot of work has been done to try to determine which property or properties may explain the behaviour of the corresponding cast PBX composition. But up to now, and despite an international inter‐laboratory comparison (Round Robin) of seven lots of RDX from five different manufacturers conducted from 2003 to 2005, even if some techniques lead to interesting results, there is no dedicated specification to apply to RS‐RDX. This quality (I‐RDX®) has proved to retain its low sensitivity even after ageing, which does not seem to be the case for standard RDX produced by the Bachmann process (when re‐crystallized under I‐RDX conditions in order to obtain RS‐RDX). It has been shown that the higher sensitivity of RDX produced by the Bachmann process, or the evolution of sensitivity after ageing of RS‐RDX produced from Bachmann RDX may be linked to the presence of octogen (HMX) during the crystallization process. In order to check such hypothesis, low HMX content RDX produced by the Bachmann process has been prepared and evaluated in cast PBX composition (PBX N 109). Results of the characterization of such quality of RDX and its evaluation in cast PBX composition as well as ageing behaviour are presented and discussed; there are indications that removal of HMX from Bachmann RDX may lead to RS‐RDX, which retains its RS character even after ageing. 相似文献
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以30 mm高压模拟炮为试验平台,以单基发射药为参照,研究了3种典型叠氮硝胺(DIANP)发射药的动态燃烧稳定性,分析了配方组成对DIANP发射药起始燃烧特征、膛内压力上升过程及膛内压力波动的影响,探讨了DIANP发射药配方组成与其起始燃烧特征、膛内压力上升特点和压力波强度的相互关系。结果表明,在DIANP发射药配方中添加质量分数30%的固体组分黑索今(RDX)或硝基胍(NGU),发射药膛内动态燃烧稳定性增加,膛压-时间曲线波动减小,膛压从30 MPa增至50 MPa所需的时间分别增加了92%和78%,起始负压差从-40.7 MPa降低至-4.44 MPa和-10.66 MPa。在DIANP发射药体系引入高含量的固体组分RDX或NGU,由于低压下RDX分解前熔融吸热,而NGU火药燃烧表面存在坚实熔融层,均可有效减小DIANP发射药起始燃气的生成速率,降低发射装药起始燃气生成猛度,缓减起始阶段膛内压力的上升,提高药床起始燃烧一致性,减小膛内压力波强度。 相似文献