含快燃物改性双基推进剂燃速模型的建立

建立了含4种不同晶形快燃物(立方体、球形、长方体、片状)无烟改性双基推进剂的燃烧数学模型,推导出推进剂燃速数学表达式,以及在推进剂燃烧方向上快燃物有效使用粒径的数学表达式。运用建立的数学模型分别计算了含5％和7％快燃物ACP的某推进剂在不同压强下的燃速,计算结果与实测燃速基本吻合。     

加速度对丁羟推进剂燃速影响的研究

通过试验研究了加速度场中丁羟推进剂的燃速的加速度敏感性。另外从加速度力作用下燃烧区压缩导致热反馈增大角度出发,建立了加速度条件下推进剂稳态燃烧模型,并编程计算、分析了影响推进剂燃速敏感性的因素,可为发动机内弹道设计提供参考。     

醇胺类键合剂在丁羟推进剂中的应用进展

介绍醇胺类键合剂的发展现状,分析键合剂在复合推进剂中的键合机理及其在丁羟推进剂中的应用,总结了醇胺类键合剂在应用中所存在的问题及发展趋势。认为醇胺类键合剂可明显改善丁羟推进剂的性能。     

用ACP提高固体推进剂的燃速

用快燃物ACP提高改性双基推进剂、AP／HTPB复合推进剂和N-15D推进剂的燃速,取得了非常显著的效果。在HMX和RDX改性双基推进剂配方中加入不同粒度不同含量的ACP,推进剂的燃速均能提高,压强指数基本无变化。在AP基复合推进剂配方中加入ACP,其燃速均有不同程度的提高,而且在7～15MPa的压强范围内,压强指数小于0．45。成功地进行Ф64mm发动机试验,并获得稳定的P-t曲线。N-15D推进剂配方的燃速较低,加入ACP后,燃速也有提高,压强指数稍有增大。结果表明,加入ACP后燃速提高效率分别是：HMX改性双基推进剂配方为40．62％,RDX改性双基推进剂配方为38．00％,复合推进剂配方为37．35％,N-15D推进剂配方为9．90％。     

生物技术在复合固体推进剂中的应用研究进展及展望

从生物合成和生物降解两个角度展望了生物技术在复合推进剂原料合成和降解处理中的应用前景,包括生物基含能材料前体、生物基黏合剂前体、生物合成的无机纳米材料以及端羟基聚丁二烯(HTPB)降解菌、高氯酸铵(AP)降解菌和黑索今/奥克托今(RDX/HMX)降解菌。在生物合成方面,可再生的生物质材料不仅可以用于合成相对应的硝酸酯和芳香族含能化合物,还可以聚合为可初步满足固体推进剂性能需求的黏合剂,降低化工合成所带来的浪费与污染。而由生物方法所合成的无机纳米材料种类远超过传统化学方法,这极大拓展了固体推进剂功能助剂的筛选范围,进一步提升推进剂性能。在生物降解方面,HTPB降解已经具备了一定的理论和实验基础,为该技术的进一步发展奠定了基础。AP、RDX、HMX降解已经初步具备了工程应用的能力,可用于废弃含能材料的处理和环境污染修复。附参考文献98篇。     

丁羟高燃速推进剂配方研究

介绍丁羟高燃速推进剂研究的必要性和主要技术途径。重点阐述了已经研制出的燃速为80mm/s(6.85MPa)的丁羟高燃速配方。该配方不仅燃速高,而且综合性能良好,有实用价值。     

丁羟推进剂的应用发展

本文介绍了端羟聚丁二烯(HTPB)推进荆的发展概况,简述了端羟聚丁二烯(HTPB)粘合剂及其性能.叙述了丁羟推进剂的进展及应用情况,指出了高能量、高燃速和无烟丁羟推进剂研究方向和在此过程中所要解决的关键问题.     

丁羟复合推进剂的辐射点火

采用CO2激光点火装置,对丁羟复合推进剂的点火过程进行了实验研究,利用描述固体推进剂物化现象的一维传热模型对复合推进剂的辐射点火特性进行了理论分析。通过最小二乘法拟合实验数据得到了丁羟复合推进剂的点火准则。结果表明,丁羟复合推进剂的点火过程主要包括惰性加热及气相点火过程,惰性加热时间和点火延迟时间随热流密度的增大而减小,且随着热流密度的增大,热流密度的影响逐渐降低。固相传热数学模型能够比较准确地描述复合推进剂的辐射点火特性。     

湿度对丁羟推进剂及其粘接性能的影响研究

固体火箭发动机燃烧室内绝热层、人工脱黏层及推进剂药柱,均为高分子材料复合体系。在成型及贮存过程中,湿度是影响丁羟推进剂药柱性能及各界面的联合粘接强度的首要因素。探讨了绝热层、衬层及推进剂药柱在不同环境湿度下的吸湿特性,通过模拟实际生产过程的环境湿度,研究了丁羟推进剂药柱性能及各界面的联合粘接强度变化状况。     

丁羟三组元推进剂的增材制造及性能研究

针对传统浇注成型与直写式3D打印对固体推进剂药浆工艺性能要求相冲突的问题,为实现小型药柱的3D打印,采用添加少量定型助剂(YJ)的方法对丁羟三组元推进剂配方进行改性,对改性前后推进剂的工艺性能、力学性能、燃烧性能和能量性能进行对比分析,并探究了YJ对推进剂性能的影响。结果表明,改性后的推进剂药浆具备可控挤出和室温堆积的流变特性;YJ的加入使得推进剂在20、70℃下的最大抗拉强度分别降低0.1和0.15MPa,断裂伸长率分别增加了12.7%和9.9%,表明YJ对其力学性能影响显著;此外,实验及理论计算表明,YJ对推进剂的燃烧性能和能量性能影响甚微,燃速最大降低0.24mm/s,能量变化幅度均在1%以内;表明定型助剂(YJ)的加入不仅使药浆满足3D打印要求,而且对原始推进剂的整体性能没有显著负面影响。     

呋咱类含能化合物及其在推进剂中的应用

讨论了呋咱类含能化合物的分子结构特点和理化性质,综述了典型呋咱化合物即单呋咱、链状呋咱及大环呋咱、稠环呋咱的合成方法,总结了该类含能化合物在推进剂中的应用情况。认为呋咱类含能化合物由于其优良的性能。在推进剂中有广泛的应用前景。     

Estimation of Aluminium in HTPB Based Composite Solid Propellants by hydrogen evolution method

Hydrogen gas evolution method has been applied to determine the percentage of aluminium (Al) in hydroxy-terminated polybutadiene (HTPB) based composite solid propellants premix/pastes. The determination is not effected by the presence of Zn, Fe, Cu or small amounts of silicon but magnesium has been found to interfere in the analysis. The results are obtained with remarkable accuracy and reproducibility.     

Mechanical Properties of Composite AP/HTPB Propellants Containing Novel Titania Nanoparticles

Modern chemical synthesis techniques have allowed for improved incorporation of nano‐scale additives into solid propellants. Various methods were implemented to incorporate titania nanoparticles into three representative ammonium perchlorate composite propellants (APCP), and the mechanical properties of each formulation were tested and compared to those of an analogous baseline. Advanced imaging techniques were applied to all particle synthesis methods to characterize particle size and particle network type and size. Uniaxial tensile testing was performed to measure propellant ultimate strength, ductility, and elastic modulus. In general, the addition of nano‐titania additives to the propellant decreased propellant strength and modulus, but improved ductility. Propellant formulations containing in‐situ titania exhibited an increase in ductility of 11 %, 286 %, and 186 % with a corresponding reduction in strength of 82 %, 52 %, and 17 % over analogous baselines. These trends corresponded to a simultaneous decrease in propellant density, indicating that when implementing nano‐sized additives, care must be taken to monitor the effect of the altered manufacturing techniques on propellant physical properties in addition to just monitoring burning rates. Tailoring of propellant manufacturing procedures and the addition of Tepanol bonding agent to an in‐situ APCP formulation fully recovered the propellant density and ultimate strength while retaining the enhanced ductility.     

Iron Nanoparticle Additives as Burning Rate Enhancers in AP/HTPB Composite Propellants

Burning rate measurements were carried out for ammonium perchlorate/hydroxyl‐terminated polybutadiene (AP/HTPB) composite propellants with iron (Fe) nanoparticles as additives. Experiments were performed in a strand burner at pressures from 0.2 to 10 MPa for propellants containing approximately 80 % AP and Fe nanoparticles (60–80 nm) at concentration from 0 to 3 % by weight. It was found that the addition of 1 % Fe nanoparticles increased burning rate by factors of 1.2–1.6. Because Fe nanoparticles are oxidized on the surface and have high surface‐to‐volume ratio, they provide a large surface area of Fe₂O₃ for AP thermal decomposition catalysis at the burning propellant surface, while also providing added energy release due to the oxidation of nanoparticle sub‐shell Fe. The increase in burning rate due to Fe nanoparticle content is similar to the increase in burning rate caused by the addition of iron oxide (Fe₂O₃) particles observed in prior literature.     

Development of MTV Compositions as Igniter for HTPB/AP Based Composite Propellants

MTV compositions were prepared by keeping the magnesium/Teflon ratio constant and increasing the Viton content of the mixture up to 14% by an increment of 2% to investigate the effect of binder content on the heat of explosion, which is found to increase with the increasing Viton percentage as the magnesium content concomitantly goes down toward the stoichiometric value. In the second part of the study, fuel-rich MTV compositions were prepared by changing the magnesium content and keeping the Viton fraction constant at a specific value to investigate the effect of magnesium content on the heat of explosion and combustion characteristics. The observed general trend is that the heat of explosion of MTV compositions decreases as the magnesium content increases. All the MTV compositions were tested in a closed vessel to measure the maximum pressure achieved and the rate of reaching this pressure. The ignition performance of three selected MTV compositions was examined in 2.75 inch rocket motor by using the same charge of igniter and the same HTPB/AP composite propellant of the equal amount in each test. Two of them have excellent ignition performance and, therefore, can be used as igniter for the HTPB/AP based composite rocket propellants.     

Differential Scanning Calorimetric Study of HTPB based Composite Propellants in Presence of Nano Ferric Oxide

A comparative study of the thermal decomposition of ammonium perchlorate (AP)/hydroxy terminated polybutadiene (HTPB) based composite propellants has been carried out in presence and absence of nano iron oxide at different heating rates in a dynamic nitrogen atmosphere using differential scanning calorimetry. The pronounced effect was a lowering of the high temperature decomposition by 49 °C. A higher heat release up to 40% was observed in presence of nano ferric oxide (3.5 nm). The kinetic parameters were evaluated using the Kissinger method. The increase of the rate constant in the catalyzed propellant confirmed the enhancement of the catalytic activity of ammonium perchlorate. The scanning electron micrographs of nano Fe₂O₃ incorporated in HTPB revealed a well‐separated characteristic necklace‐like structure of α‐Fe₂O₃ particles at high magnification.     

HTPB推进剂危险性实验研究

依据联合国危险品分级方法,探讨了热刺激、机械刺激和冲击波刺激对低燃速HTPB推进剂、高燃速HTPB推进剂和四组元HTPB推进剂危险性的影响。结果表明,3种HTPB推进剂的热安定性良好,但对火焰热刺激均十分敏感,具有爆燃性;高燃速HTPB推进剂对机械刺激也极其敏感,摩擦感度(p)为96%,撞击感度特性(H50)为37.2 cm。在无约束条件下,3种HTPB推进剂裸药柱对雷管爆轰作用不敏感,而在钢管的强约束条件下,四组元HTPB推进剂对爆轰冲击波作用敏感,隔板值大于18mm。     

Energetic Abilities of Solid Composite Propellants Based on 3,4,5-Trinitropyrazole and Ammonium Dinitramide

The investigation aims at the expansion of the basis of formulations of solid composite propellants by introducing new compositions with lower sensitivity to mechanic impact and improved thermal stability.The formulations based on trinitropyrazole(TNP)contains a binder(a hydrocarbon or active one),aluminum and inorganic oxidizer ADN.The results show that a binary formulation TNP+active binder(18%-19%)(volume fraction)with no metal is well designed which would achieve high specific impulse(at Pc∶Pa=40∶1)of 248s,high density of 1.80g/cm3 and combustion temperature Tcabout 3 450K.In terms of energy,metal-free compositions with TNP lose a bit to those with HMX,only if HMX fraction in formulation is higher than 45%-50%.