共查询到20条相似文献，搜索用时 15 毫秒
1.
Satyanarayanan&#x;R. Chakravarthy Jeffrey&#x;M. Freeman Edward&#x;W. Price Robert&#x;K. Sigman 《Propellants, Explosives, Pyrotechnics》2004,29(4):220-230
This paper reports a series of experiments involving ammonium dinitramide (ADN), a new energetic oxidizer of potential use in composite solid propellants. The experiments include (a) self‐deflagration of pressed pellets of ADN; (b) combustion of sandwiches with ADN laminae on both sides of a binder lamina that is either “pure” or filled with particulate oxidizer and other additives; and, (c) combustion of propellants with a bimodal oxidizer size distribution, wherein, combustion of coarse ADN and fine AP (ammonium perchlorate) and vice versa were used, in addition to mixtures of coarse ADN and AP, fine ADN and AP, and all‐ADN or all‐AP formulations. 相似文献
2.
Kala&#x;P.&#x;C. Rao Aarun&#x;K. Sikder Mahadev&#x;A. Kulkarni Melind&#x;M. Bhalerao Balkrishna&#x;R. Gandhe 《Propellants, Explosives, Pyrotechnics》2004,29(2):93-98
The laboratory synthesis of the energetic plasticizer n‐buNENA was scaled up to one kg batch size and the compound was fully characterized by spectral data and elemental analysis. N‐buNENA was formulated with CMDB and EDB propellant compositions. The results showed an improvement in mechanical properties and burning rate over a wide range of pressure along with acceptable limits of hazard and thermal stability as compared to DEP based propellant systems. 相似文献
3.
Although ammonium dinitramide (ADN) has been targeted as a potential green monopropellant in future space vehicles, its application potential in Micro-electrical-Mechanical System (MEMS) thrusters or microthrusters has been seldom reported in open literature. In this paper, electrolytic decomposition of Ammonium Dinitramide (ADN)-based liquid monopropellant FLP-103 was carried out in an open chamber and MEMS thrusters were fabricated from poly-dimethylsiloxane (PDMS) to characterize the power consumption. Two thrust measurement methods were employed to investigate the electrolytic decomposition of FLP-103 in MEMS microthrusters. The results show that the monopropellant can be successfully ignited at room temperature through 80 V, 0.1 A (8 W) using copper wire as electrodes. In the current thruster design, low thrust was obtained at FLP-103 flowrate of 40 μl·min-1 but it generated the highest specific impulse, Isp, among all the flowrates tested. The experiments successfully demonstrated the potential application of electrolytic decomposition of FLP-103 in MEMS thrusters. 相似文献
4.
David&#x;E.&#x;G. Jones Richard Turcotte Robert&#x;C. Fouchard Queenie&#x;S.&#x;M. Kwok Anne‐Marie Turcotte Zainab Abdel‐Qader 《Propellants, Explosives, Pyrotechnics》2003,28(3):120-131
The thermal behaviour in air of two Al nanopowders, Alss and Alsstef, a Teflon coated version of Alss, was determined using DSC, TG‐DTA and accelerating rate calorimetry (ARC). Compared to two larger Al nanopowders, for which hazards results have been reported, Alss and Alsstef are less reactive in air, possibly due to the nature of the passivating and coating layers. The stability of Alss and Alsstef in a wet environment was also investigated using ARC. Alss is very reactive with water, which could lead to a problem of aging in a humid atmosphere. The ”coating” of Alsstef significantly reduces the reactivity of Alss with water. Outgassing behaviour of mixtures of ADN, GAP and various Al powders was investigated using TG‐DTA‐FTIR‐MS. No chemical interactions were observed between ADN/Al, GAP/Al and ADN/GAP. The effect of the addition of Al nanopowders on the thermal decomposition of ADN and GAP was studied using ARC. Al nanopowders had a minor effect on the thermal stability of ADN, while the addition of Alss and Alsstef lowered the onset temperature of GAP. The electrostatic discharge (ESD), impact and friction sensitivities of Al nanopowders and their mixtures with ADN and GAP were also determined. Al nanopowders appear to sensitize ADN to ESD, impact and friction. 相似文献
5.
Two dinitramide salts with very high heat of formation have been identified, i.e. triaminoguanidine dinitramide (TAGDN) and guanylazide dinitramide (GADN). Thermochemical calculations showed that TAGDN‐propellants have a higher impetus than the corresponding GADN‐propellants at a given flame temperature. Due to the fact that a low flame temperature has to be prefered in a gun, TAGDN seems better suited as a component in gun propellants compared to GADN. TAGDN was thus synthesized, analyzed and characterized to determine some of its properties. 相似文献
6.
Subbiah Venkatachalam Gopalakrishnan Santhosh Kovoor Ninan&#x;Ninan 《Propellants, Explosives, Pyrotechnics》2004,29(3):178-187
In recent years, there has been a considerable interest in the development of novel type of high performance propellants for use in solid rocket motors. Ammonium salt of dinitramidic acid NH4N(NO2)2 (ADN) has attracted wide interest as a potentially useful energetic oxidizer for rocket propellants because of its clean and environment‐friendly exhaust products during burning. ADN contains one N (NO2)2 group and its synthesis requires new type of N‐nitration. The present paper reviews the general synthetic methods used for the synthesis of inorganic, organic and metal dinitramide salts and their properties, with a special emphasis on ammonium dinitramide. The salient features with reference to the extent of conversion and ease of separation of the products of the various synthetic methodologies are also addressed. 相似文献
7.
Robert Kellogg Saul Lapidus Trevor Hedman Joseph Kalman 《Propellants, Explosives, Pyrotechnics》2020,45(3):480-485
Ammonium perchlorate is commonly used as an oxidizer in solid rocket propellant. Having a knowledge of its thermal expansion properties is essential for its application in different environments. Knowledge of thermal expansion properties is also useful for the prediction of propellant mechanical properties and response of propellant slow cook off applications. X-ray diffraction analysis was performed on ammonium perchlorate at temperatures ranging from 260 K to 500 K. From there, Bragg peaks were indexed by fitting theoretical values of 2θ to the 2θ values of peaks obtained from the experiment. The Miller indices along with the 2θ values were then used to solve for the lattice parameters at each temperature. The lattice parameters, in nanometers, range from 0.9201 to 0.9373, 0.5805 to 0.5865, and 0.7439 to 0.7535 for a, b, and c, respectively. The measurement of the lattice parameter expansion leads to the determination of the temperature dependent thermal expansion coefficients within the temperature range. The lattice parameter values also lead to the determination of strain and stress on the ammonium perchlorate crystal. Direct measurement of the strain within the crystal lattice provides a more accurate measurement method over traditional optical-based techniques. 相似文献
8.
Ammonium dinitramide (ADN) was characterized during recrystallization from the melt. The surface tension of molten ADN at 97 °C was measured to be 89 mN/m. The wetting angles between molten ADN and different solid surfaces (polytetrafluoroethylene, glass, steel, and aluminum) were determined. The wettability depends on the surface tension of molten ADN, the free surface energy of the solid surfaces and the interfacial tension between the solid and liquid. Observations of the recrystallization behavior of molten ADN showed that nucleation does not occur, even at super cooling rates of 70 K. Crystallization can be initiated by the application of seed crystals. 相似文献
9.
Makoto Kohga 《Propellants, Explosives, Pyrotechnics》2011,36(1):57-64
The burning rate of AP/HTPB composite propellant increases with increasing AP content and with decreasing AP size. In addition, the burning rate can be enhanced with the addition of Fe2O3. The burning characteristics and thermal decomposition behavior of AP/HTPB composite propellant using coarse and fine AP particles with and without Fe2O3 at various AP contents were investigated to obtain an exhaustive set of data. As the AP content decreased, the burning rate decreased and the propellants containing less than a certain AP content self‐quenched or did not ignite. The self‐quenched combustion began at both lower and higher pressures. The lower limit of AP content to burn the propellant with coarse AP was lower than that with fine AP. The lower limit of AP content to burn was decreased by the addition of Fe2O3. The thermal decomposition behavior of propellants prepared with 20–80 % AP was investigated. The decrease in the peak temperature of the exothermic decomposition suggested an increased burning rate. However, a quantitative relationship between the thermochemical behavior and the burning characteristics, such as the burning rate and the lower limit of AP content to burn, could not be determined. 相似文献
10.
Eva Landsem Tomas L. Jensen Finn K. Hansen Erik Unneberg Tor E. Kristensen 《Propellants, Explosives, Pyrotechnics》2012,37(6):691-698
Ammonium dinitramide (ADN) is a high performance solid oxidizer of interest for use in high impulse and smokeless composite rocket propellant formulations. While rocket propellants based on ADN may be both efficient, clean burning, and environmentally benign, ADN suffers from several notable disadvantages such as pronounced hygroscopicity, significant impact and friction sensitivity, moderate thermal instability, and numerous compatibility issues. Prilled ADN is now a commercially available and convenient product that addresses some of these disadvantages by lowering the specific surface area and thereby improving handling, processing, and stability. In this work, we report the preparation, friction and impact sensitivity and mechanical properties of several smokeless propellant formulations based on prilled ADN and isocyanate cured and plasticized glycidyl azide polymer (GAP) or polycaprolactone‐polyether. We found such propellants to have very poor mechanical properties in unmodified form and to display somewhat unreliable curing. However, by incorporation of octogen (HMX) and a neutral polymeric bonding agent (NPBA), the mechanical properties of such smokeless formulations were significantly improved. Impact and friction sensitivities of these propellants compare satisfactorily with conventional propellants based on ammonium perchlorate (AP) and inert binder systems. 相似文献
11.
火药热分解特性与燃烧稳定性间相关性的分析 总被引：1，自引：1，他引：0
火药热分解过程的复杂性与其燃烧稳定性之间,存在有某种统计性的增函数关系。火药热分解特性对其燃烧特性的影响,是通过燃烧过程中亚表面热分解表观活化能的变化来实现的,当环境温度和压力较低时,亚表面的热分解特性,与常规条件下该火药的热分析结果相近。对于热分解过程较为复杂的火药,随着环境压力和温度的升高,其亚表面的分期机理和表观分解活化能将发生改变,亚表面分解速率随压力的变化规律也要发生变化,这就导致了燃烧过程的不稳定性,而对于那些热分解过程较为简单的火药,则不会出现这种情况,此外,本文还提出,火药中某些组分的爆燃是导致一些火药燃速压力指数较高的原因。 相似文献
12.
《Propellants, Explosives, Pyrotechnics》2018,43(6):609-615
Ammonium DiNitramide (ADN) is an interesting oxidizer to replace ammonium perchlorate in the composition of solid propellants. In this study, Spray Flash Evaporation (SFE) is presented as a new technology to enhance stability of ADN by crystallization of nanoparticles. The crystallinity and purity of the compound was confirmed by X‐Ray Diffraction and Raman analysis. An average diameter of spherical particles around 32 nm (solution of ethyl acetate) and 34 nm (solution of methyl acetate) was measured by Scanning Electronic Microscopy (SEM). Furthermore, the downsizing to nanoscale induces a slower moisture absorption kinetic under 55 % of relative humidity, a reduction of the critical diameter of detonation and the desensitization to impact. 相似文献
13.
Yonis Ahmed Ashlee Quintana Gregory Warmoth Stephan Deplazes Adam Brand Jeffrey Mills Stefan Schneider 《Propellants, Explosives, Pyrotechnics》2019,44(9):1129-1138
Deep Eutectic Solvents show the low volatility/toxicity of “classical” Ionic Liquids. The formation of a Deep Eutectic Solvent from two solids is the result of intermolecular bonds being weakened or broken and rearranged in completely new networks. The effect of these new bonding arrangements on physical properties like melting point, thermal stability, density, viscosity, and impact sensitivity of some binary mixtures of energetic nitrate salt and nitrogen containing ligands was investigated. With some exceptions the liquids showed increased sensitivity compared to their solid ingredients, which suggest that this might provide an ON‐switch for sensitivity. Furthermore, applying the Deep Eutectic Solvent concept to propellant and explosive development may allow incorporation of established energetic solids into liquid applications. 相似文献
14.
Bo Jin Rufang Peng Shijin Chu Yiming Huang Rong Wang 《Propellants, Explosives, Pyrotechnics》2008,33(6):454-458
Three types of [60]fullerene crystals were obtained. The first one was the direct commercial [60]fullerene, and the other two were recrystallized from the first one in carbon bisulfide and in carbon bisulfide/petroleum ether, respectively. Scanning electron microscopy (SEM), X‐ray powder diffractometry (XRD), and FT‐IR spectrometry were used to study the physical characteristics of the crystals. The thermal stability of the three [60]fullerene crystals was studied by differential thermal analysis (DTA), and the effects of the three [60]fullerenes on the mechanical sensitivity and friction sensitivity of HMX were tested and analyzed. It was found that the three types of [60]fullerenes have different thermal stabilities, and the friction and impact sensitivities of HMX are reduced from 100% to 70% and to 60%, respectively when 1% [60]fullerene 3 was added in HMX. 相似文献
15.
Beat&#x;P. Berger Jrg Mathieu Patrick Folly 《Propellants, Explosives, Pyrotechnics》2006,31(4):269-277
Ammonium dinitramide is planned to be a substitute for commonly used oxidizers in rocket motor compositions. Different teams worldwide have already synthesized alkali salts of dinitramide and several times it was used as an oxidizer for pyrotechnic compositions containing boron as a reducing agent. In this paper the results of a systematic investigation to characterize the pyrotechnic redox systems titanium/potassium dinitramide and titanium/cesium dinitramide are presented and the data are compared. The heats of reaction as well as the burning rates of the redox system titanium/potassium dinitramide are higher than those of the redox system titanium/cesium dinitramide. Both systems show a moderate sensitivity to friction and electrostatic discharges. However the sensitivity of mixtures of both redox systems shows a very high sensitivity to impact. These sensitivities are in the range of pure HMX or pentaerythritol tetranitrate. 相似文献
16.
Tomasz Go&#x;ofit Pawe&#x; Maksimowski Ariel Biernacki 《Propellants, Explosives, Pyrotechnics》2013,38(2):261-265
The synthesis of potassium dinitramide (KDN), an intermediate in the ammonium dinitramide (ADN) synthesis, was optimized to reduce the costs of the ADN synthesis in order to facilitate competitiveness of this oxidizer with ammonium perchlorate (AP). The optimal conditions for the synthesis of KDN like feedstock molar ratio, nitration time, and temperature were determined. KDN was obtained in ca. 48 % yield. The modifications introduced allowed to reduce feedstock consumption and energy intensity of the process. 相似文献
17.
Mathias Persson Kjell Anflo Pete Friedhoff 《Propellants, Explosives, Pyrotechnics》2019,44(9):1073-1079
The flight heritage for ECAPS’ propulsion technology based of Ammonium DiNitramide (ADN), started 2010 with a successful 5 years on orbit demonstration mission of the PRISMA satellite. Since 2016, launches of satellites from 3 different continents continues to add to the flight heritage. Thirteen SkySat earth observation satellites with ADN‐based propulsion have added more than 28 years of accumulated flight heritage for LMP‐103S and ECAPS’ 1 N HPGP thrusters. 相似文献
18.
19.
Marc Comet Cédric Schwartz Franck Oudot Fabien Schnell Denis Spitzer 《Propellants, Explosives, Pyrotechnics》2020,45(10):1600-1606
The purpose of this article is to alert our peers on the danger faced by those who carry out experiments involving molten ammonium dinitramide (ADN). In recent experiments aiming at preparing submicron particles of this compound, a preliminary study of the sensitivity to impact of molten ADN was performed. These first tests have shown that the sensitivity threshold of molten ADN to impact is more than one order of magnitude lower that the one on solid ADN (<0.25 J vs. 4 J) and similar to the one of nitroglycerin (<0.25 J), making liquid ADN extremely hazardous to handle. Detonation tests, which were performed in strong steel sheaths open to one end, have shown that the initiation of the detonation and its subsequent propagation occur both in solid and liquid ADN charges, having a diameter of only 4 mm. The critical diameter of solid ADN which is between 25 and 40 mm according to literature, is therefore decreased by at least an order of magnitude when ADN is placed in strong metallic confinement. On the other hand, the detonation of liquid ADN produces stronger destructive effects than the detonation of solid ADN, meaning that the detonation mechanisms of this explosive are different in its two physical states. In conclusion, liquid ADN must be considered in practice as a more hazardous and powerful explosive than solid ADN. This raises the issue of all experiments in which ADN is likely to be formed in molten state. 相似文献
20.
Ammonium nitrate (AN)‐based composite propellants have attracted much attention, primarily because of the clean burning nature of AN as an oxidizer. However, such propellants have some disadvantages such as poor ignition and low burning rate. Ammonium dichromate (ADC) is used as a burning catalyst for AN‐based propellants; however, the effect of ADC on the burning characteristics has yet to be sufficiently delineated. The burning characteristics of AN/ADC propellants prepared with various contents of AN and ADC have been investigated in this study. The theoretical performance of an AN‐based propellant is improved by the addition of ADC. The increase in the burning rate is enhanced and the pressure deflagration limit (PDL) becomes lower with increasing amount of ADC added. The increasing ratio of the burning rate with respect to the amount of ADC is independent of the AN content and the combustion pressure. The optimal amount of ADC for improving the burning characteristics has been determined. 相似文献