bluuebunny/crossref_metadata_2025 huggingface dataset:
Thermal Decomposition of Energetic Materials. 40. Fast thermolysis patterns of Alkanediammonium dinitrate salts
Authors: Russell T. P. , Brill T. B.
Published: May 2005

Rapid‐scan FTIR/temperature profiling studies of the fast thermal decomposition of alkanediammonium dinitrate salts [H3N(CH2)nNH3](NO3)2, n = 1–4 and 6, are described. All of the salts liberate HNO3 and NH3 early in the first stage. When n = 1–3, small molecule products from redox reactions occur in the second stage of decomposition. When n = 4, 6, the second stage involves cycloclimination to form pyrrolidine (n = 4) and α‐ethlypyrrolidine (n = 6). The temperature of the onset of thermal decomposition is lower when n = 1 than when n is larger. Intra‐ and intermolecular hydrogen bonding are proposed to play a significant role in these decomposition patterns.
On the study of micromechanism governing Detonation Initiation of Nitramines and Nitrosamines
Authors: Zeman Svatopluk , Dimun Milan
Published: May 2005

On the basis of the published knowledge on micromechanism of detonation initiation, existence was predicted and indirectly proved of the direct relationship between activation energies of low‐temperature non‐autocatalyzed thermolysis of nitramines and nitrosamines, on the one hand, and their sensitivity to impact, on the other. The said relationship is presented as another piece of evidence of identity of the primary fragmentation in the detonation conversion of the above‐mentioned compounds with the primary fragmentation in their thermolysis. At the same time, there was taken notice of the higher thermal reactivity of nitrosamines as compared with their nitramine structural analogues.
The manufacture of high performance composite propellants and novel charges by Batch and Continuous Extrusion Processes
Authors: Cooke E. M. G.
Published: May 2005

Recent developments in extrudable composite propellant technology enable higher energy/density formulations and novel charges to be successfully manufactured, which cannot be produced by castable composite technology processes. These also offer substantial capital, labour and time savings in certain production applications.

New heavy duty processing machines have been developed recently, which have been used successfully for the safe and efficient manufacture of new high energy/fast burning rate composite propellants, using batch and continuous processes. These include injection flow forming techniques and die extrusion processes for filling rocket motors. A range of non‐energetic binder systems based on non‐curing plastic, curing HTPB and TPE binder systems have been successfully manufactured.
2,6‐Diarylmethylene‐thiazolo[3,2‐a]pyrimidine‐3,5,7‐triones as Stabilizers for Double‐Base Propellant
Authors: Soliman Adly A.‐W. , El‐Damaty A. A. , Awad W. H. E.
Published: May 2005

2,6‐Diphenylmcthylene‐thiazolo‐pyrimidine‐trione, the o‐, m‐, and p‐nitrophenyl‐derivatives were prepared and incorporated as stabilizers in a double base smokeless powder. The prepared powders were subjected to some standard qualitative and quantitative stability tests. It was found that the 2,6 diphenyl trione (Ia) has a good stabilizing effect for double‐base propellants.
Temperature sensitivity of magnesium‐sodium nitrate propellants
Authors: Singh Harihar , Bhaskara Rao R.
Published: May 2005

Temperature sensitivity of burning rate of magnesium‐sodium nitrate propellants has been determined at different mixture ratios in the temperature range between – 40°C and + 50°C. The results indicate that the temperature sensitivity is minimum at high magnesium loadings and increases as the proportion of magnesium in the mixture decreases. Thermal decomposition data indicate that the oxidation of magnesium with sodium nitrate in a propellant is governed by the condenscd phase heat release. This heat which is maximum at high fuel concentration is seen as causing prcssure independent, high burning rate with low temperature sensitivity. The reduction of magnesium content in the mixture increases the metal agglomeration on the surface of the propellant and causes for the decrease of condenscd phasc heat release and the reaction zone temperature. This causes for pressure dependent, low buring rate with high temperature sensitivity. The burning surface temperature data indicate that the change in the initial temperature of the propellant at low fuel concentration might be causing for the change in the degree of mctal agglomcration which lead to the increase of temperature sensitivity of burning rate. The photographs of the sliver surface obtained after static test at different initial temperature of the propellant support the suggested mechanism.
Friction sensitivity mechanism of Ammonium Perchlorate Composite Propellants
Authors: Bazaki H. , Kubota N.
Published: May 2005

Friction sensitivity of ammonium perchlorate (AP) composite propellants has been studied experimentally by means of thermal analysis and micro‐thermocouple techniques. Several types of catalysts were mixed with AP in order to examine the effect of the reactivity on the sensitivity. The results of friction sensitivity test show that the samples are sensitized when the concentration of catalysis which are used for high burning rate propellants is increased. Metal contents within the catalysts tend to give some effects on the friction sensitivity. Based on the results of the temperature profile measurements in combustion waves, it is found that the friction sensitivity is correlated with the burning surface temperature of the propellants. The catalysts which accclerate the AP decomposition are responsible for the friction sensitivity but not for the fallhammer sensitivity.
Molecular structure of the ideal solid propellant binder
Authors: Stacer Ross G. , Husband D. Mark
Published: May 2005

A study has been conducted to investigate the relationship between binder molecular structure and the mechanical/rheological properties of solid propellants. Beginning with the mechanical property requirements dictated by the motor grain operating conditions as well as rheological constraints imposed by available processing technology, the approach taken was to work backwards to obtain the ideal molecular structure of a solid propellant binder. Structural/processing requirements were determined from the demands of three typical rocket motor applications: space transfer, launch vehicle/ballistic missile, and tactical air‐to‐air. Three general formulation approaches to meet the demands of these applications were considered. These include traditional composite and nitrate ester plasticized formulation approaches, in addition to a hypothetical all‐binder propellant. For each of these three formulation approaches, a variety of polymer molecular characteristics were defined in terms of molecular weight, crosslink density, solubility parameter, chain stiffness, monomeric friction coefficient, volume fraction filler, and volume fraction plasticizer. Characterization data for ten polymeric binder systems are reported to show how their molecular architecture influences the resulting propellant properties.
Effects of liquid burn rate catalysts on Rheological Properties of High‐Energy Composite Propellants
Authors: Vuga Slobodan M.
Published: May 2005

Effects of several liquid burning rate catalysts on rheological properties of composite rocket propellants on the basis of hydroxy‐terminated polybutadiene as a binder and ammonium perchlorate as an oxidizer have been examined. Theoretical explanation of the observed effects of liquid catalysts on certain rheological properties of the mentioned propellants are given. Laboratory procedures for synthesis of used catalysts are described. The results of physico‐chemical characterization of synthesized catalyst are also presented.
Method for the Determination of the Critical Diameter of High Velocity Detonation by conical geometry
Authors: Badners Hartmut , Leiber Carl‐Otto
Published: May 2005

A critical diameter exists for both high velocity (HVD) and low velocity detonation (LVD). No relationship exists between these two diameters, however they are both dependent upon the temperature, confinement, contaminants, type of detonation and, most importantly, geometry. In cylindrical geometry, the critical diameter is determined by go/no go tests which are relatively expensive and time consuming. In this respect, there is a need for a method by which the critical diameter can be determined quickly and reliably.

A relatively simple procedure which can also be performed in the field is proposed in this article where the critical diameter is determined in principle by a single test through the application of conical geometry. However, on account of “overdrive”, the values always fall below those obtained by cylindrical geometry. Metal plating is proposed as a method of indication. The results are then compared simultaneously by optical and electrical measurements. The temperature dependence of the critical diameter of the HVD of pure nitromethane was also demonstrated by conical geometry and was compared to the values of cylindrical geometry.

The method was originally proposed as a joint US/German effort between Dr. Mallory of NSWC, China Lake, and Dr. Leiber of BICT. Since Dr. Mallory has recently passed away, the question is therefore open as to whether or not this test can be approved internationally.
Thermal Behaviour of HMX/RDX Mixtures
Authors: Quintana José R. , Ciller Juan A. , Serna Felipe J.
Published: May 2005

Thermal behaviour of HMS/RDX mixtures is studied by differential thermal analysis (DTA) and thermogravimetric analysis (TGA). It has been found that the temperature of polymorphic transformation of HMX shows an increase due to the presence of RDX. The enthalpies of the enothermic transformations depend on the composition of the mixture, and up to 30% RDX there is a linear relationship. The formation of an eutectic with a composition of 30/70 (HMX/RDX) is postulated to explain the melting processes.
Probability Estimation for the Self‐Ignition of the Gun Powder
Authors: Čolaković Miloš
Published: May 2005

A theoretical approach to the possibility of estimation of the heat development rate and heat accumulation rate until self‐ignition, is presented. Gun powder was thermally degradated until self‐ignition occures at several different temperatures in the vessels of different sizes. A microcalorimeter of the specific type was constructed for the detection of the thermal effects of the chemical degradation in the vessels of different sizes. T was measured for gun powder and for inert samples. Kinetics was calculated, and the obtained parameters were used for determination of the critical conditions of self‐ignition. In addition, diagrams are given for the time to self‐ignition determination even in the cases when critical conditions have not yet been achieved.
High Rate Decomposition of Cyclotrimethylenetrinitramine (RDX)
Authors: Krause Horst H. , Eisenreich Norbert , Pfeil Achim
Published: May 2005

RDX products obtained at high heating rates are discussed. RDX was decomposed by combustion in pressurized bomb and by short laser pulse irradiation.
Polymers with High‐Energy Substituents: Polyesters containing azidomethyl groups
Authors: Keicher Thomas , Wasmann Friedrich‐Wilhelm
Published: May 2005

This paper describes the synthesis of linear azidopolyesters which appear suitable as high‐energy binders in explosive systems. Preparation is carried out via a nucleophilic substitution reaction from the corresponding halogenic polyesters with sodium azide. In the polycondensation of the halogen derivates, the authors examined the influence of the intial compound ratio of dicarbonic acid and diol on the distribution of end groups and molecular weight. In this work it was found that the azido group could be introduced into the polyester backbone relatively easily. Some properties of polyesters are fundamentally changed through the introduction of the azido group. The changes as regards viscosity, thermal stability and glass transition temperature were documented and the friction and impact sensitivities recorded.
Optimization of Liquid Gun Propellants based on nitromethane/methanol by physical and chemical modifiers
Authors: Langer Gesa , Schmid Helmut , Koppenhöfer Wolfgang
Published: May 2005

Main topics of developing and optimizing liquid gun propellants are the suppression of oscillations, and increase in performance and an improvement of electrical conductivity. Additives for the liquid system nitromethane/methanol will be described, that will change the evaporation and reaction kinetics by varying the physical and chemical properties. This will lead to an improved escillation behavior.

Energetic additives, based on organic azido‐compounds, will cause a significant enhancement in performance. The electrical conductivity is improved by special compounds on the base of transition metal nitrates.

The investigations show a small effect of the physical modifiers. A significant suppression of oscillations is reached by mechnistical additives. Using these additives, the interaction of the specific energy with an accompanying increase in intensity of oscillation ‐ will be minimized. As a consequence, the possibility of an additional enhancement in performance is given, due to the developed energetic additives.
Dynamic Behavior of Composites under Preloading
Authors: Geißler Adam , Geißler Egon
Published: May 2005

Polymers with characteristic damping properties are obtained by compounding them with additives. The mechanical behavior under vibration conditions of these compounds is characterized by dynamic moduli which depend on the static preload. The test results of a PU‐compound are presented in this paper. The obtained results enable one to calculate the complex moduli of a special dynamic constitutive equation, which then enables one to calcualte stress and strain of dynamic deformations of structures under static preload. The paper presents a method to calculate such loading conditions on a system, too. A finite element analysis is used to determine the frequency response which characterizes the damping behavior of the structure.
Synthesis of N‐2,4,6‐trinitrophenyl‐N'‐2,4‐dinitrobenzofuroxano‐3,5‐dinitro‐2,6‐diaminopyridine
Authors: Naixing Wang , Boren Chen , Yuxiang Ou
Published: May 2005

N‐2,4,6‐trinitrophenyl‐N' ‐2,4‐dinitrobenzofuroxano‐3,5‐dinitro2,6‐diaminopyridine has been synthesied from 2,6‐diaminopyridine and dinitrodichlorobenzene as well as 2,4,6‐trinitrochlorobenzene. For this compound, the structure has been determined by elemental analysis, IR 1HNMR, and MS spectroscopies.
Polymer Binder for High Performance Explosives
Authors: Akhavan J. , Burke T. C.
Published: May 2005

An evaluation on coating HMX crystals with three different polymeric binders using the “solvent slurry process” was conducted. Three polymers employed were:

a thermoplastic copolymer [Kel‐F 3700],

a thermoplastic elastomer [kraton‐G 1650] and

a polyurethane [Impranil DLH].

Kel‐F 3700 presented an electrostatic hazard and was too insoluble for application by the slurry process. Kraton‐G 1650 presented a similar electrostatic hazard and its process yield was low. Impranil DLH produced a high yield using the batch slurry process.
Study of the Blast Wave Parameters from Small Scale Explosions
Authors: Ismail M. M. , Murray S. G.
Published: May 2005

Although the science of blast overpressure is well understood there are major difficulties in obtaining accurate values for peak overpressure, positive duration, and positive impulse. These parameters are required to assess damage potential of blast overpressures. This paper describes the problems associated with such measurements and how the problems can be overcome by the use of known analytical techniques based on the modified Friedlander equation. Other methods used include curve smoothing of the pressure‐time history and integration to obtain impulse values through which the curve decay parameter can be found. Several different analytical methods are compared.

The experiments have been carried out on small charges (200 g and 400 g) and the results obtained analysed to assess far‐field distances for such charges. This has been achieved by comparing peak overpressure values with the scaled distance.
On the Use of AMl and PM3 Methods on Energetic Compounds
Authors: De Paz Jose‐Luis G. , Ciller Juan
Published: May 2005

Stewart's new semi‐empirical method MNDO‐PM3 (PM3) is compared with the well known Dewar's AMl method in the study of nitrosubstituted compounds, and some energetic materials. PM3 method shows better performances than the AMl one. Adjacent lone pair/lone pair repulsion are better described at PM3 level and the known systematic correction of about −9 kcal/mol for each C‐NO2 group of the AMl method becomes +3.5 kcal/mol at PM3 level. PM3 results for N‐NO2 containing compounds are directly comparable with experimental gas phase data.
“Tris‐X”(1), A New High Energy Polynitramine Explosive: Synthesis using dinitrogen pentoxide (n2O5) technology(2), characterization, and thermal stability and hazard assessment
Authors: Millar R. W. , Paul N. C. , Richards D. H. , Bunyan P. , Golding P. , Rowley J. A.
Published: May 2005

This paper describes the synthesis and characterization of two novel heterocyclic trinitramines from readily available starting materials, as well as the evaluation of one of them (“Tris‐X”) as a high explosive. The syntheses, which utilize the ability of dinitrogen pentoxide (N2O5) to cleave aziridine rings to yield vicinal nitramine‐nitrates, proceed in high yield to give crystalline products with melting point below 100°C. The characterization of the products by IR, NMR (1H and 13C), mass spectrometry and elemental analysis is described, and whilst possessing high explosive power (the Pcj for Tris‐X is calculated at ca 300 kbar) they were found to exhibit acceptable hazard properties (impact sensitivity, temperature of ignition etc). The thermal stability measurements (by DSC and chemiluminescence) however indicated only marginally acceptable stability.
Correlation of physical and chemical properties of c‐h‐n‐o explosives (part II)
Authors: Lee Jaimin , Block‐Bolten Andrew
Published: May 2005

In our previous paper(1) we correlated the physical, chemical, and thermodynamic properties of C‐H‐N‐O explosives with their constant‐volume explosion properties calculated by using the Taylor model implemented in the Nitrodyne code. In this paper, we added the correlations for the Chapman‐Jouguet detonation properties calculated by using the Becker‐Kistiakowsky‐Wilson equation of state implemented in the TIGER code. By splitting the correlation variable (F) used in Reference 1 into a density term and a density‐independent term (f), Chapman‐Jouguet detonation pressure and velocity showed simple linear relationships with square root of the new correlation variable (f). Other detonation properties were derived from the detonation pressure and velocity: Correlation of constant‐volume explosion properties with the new correlation variable (f) showed both a moderate improvement, compared to those with the old correlation variable (F), and a much simpler relationship.
Thermal Decomposition of AMMO/AP Composite Propellants
Authors: Oyumi Yoshio , Mitarai Yoshiaki , Bazaki Hakobu
Published: May 2005

Thermal decomposition of AMMO/AP composite propellants was studied by DTA, TGA and DSC in helium atmosphere. The effects of accelerated aging at 347 K for 370 days on decomposition kinetics were also measured. AMMO/AP propellant showed two different decomposition steps, which were mainly the AMMO binder decomposed region and the reaction of AP dominated region. These regions were separated at around 20 % weight loss point at the condition used in this study. AMMO binder decomposition and AP decomposition were strongly related each other. The heat generated by the AMMO binder decomposition initiated and accelerated the thermal decomposition of AP. Although both Fe2O3 and CFe activated the thermal decomposition of AMMO/AP propellants, CFe mainly accelerated the decomposition of AMMO binder and Fe2O3 catalyzed the AP reactions which consisted of the AP decomposition and the reaction between decomposed AP and decomposed AMMO binder. AMMO/AP composite propellants were thermally stable even after aging at 347 K for 370 days.
Numerical Simulation of Penetration by explosively‐formed projectiles
Authors: Zukas J. A. , Weickert C. A. , Gallagher P. J.
Published: May 2005

Numerical solution techniques have advanced to the point where calculations of explosively‐formed penetrator formation and penetration can be performed as a matter of routine on current wave propagation computer codes, popularly known as hydrocodes. Results, however, depend to a very large extent on the experience of the code user and familiarity with the capabilities and eccentricities of the particular code used for simulations. In this paper we look at the effects of spatial resolution and material strength on the simulation of penetration of thick mild steel plates by an explosively‐formed penetrator of Armco iron. For good correlation with experiments, careful attention must be paid to the details of the computational grid. Likewise, material data must be determined from experiments appropriate for the range of strain rates encountered in the impact event.
Impact Initiated Annular Retonation Wave in explosive
Authors: Chou Pei Chi , Roslund Leslie , Liang Deshou
Published: May 2005

Experiments conducted at the White Oak Laboratory with a pentolite explosive charge impacted by a flat‐ended cylinder of mild steel, showed a hole drilled at the center of the impactor, if the explosive was detonated. A computer simulation was carried out with the finite element hydrocode DEFEL and the Forest‐Fire reaction‐rate model. Computed results verified the hypothesis that the annular retonation was the cause of the drilled hole. The detonation started at a distance of about 10 mm from the impact surface, then developed into an annular shape and propagated inwards and backwards, to the axis of symmetry and the impact surface. The converging wave generated a pressure of about 100 GPa near the center of its impact surface, which is believed to be the real cause of the hole.
Dynamic Behavior of a Shear‐Formed Shaped‐Charge Liner
Authors: Wiener K. , Shaw L. , Muelder S. , Breithaupt D. , Baum D.
Published: May 2005

A high‐resolution, multi‐frame, image‐converter camera developed for high speed photography is applied to study the dynamic behavior of shear‐formed shaped‐charge liners. Grid lines applied to the inner liner surface allow the precise quantification of liner collapse, early jet formation, and jet development for comparison with two‐dimensional hydrocode simulations. The technique affords the first direct measurement of the angular velocity of jets formed from shear‐formed shaped‐charge liners.
On the Nature of Boron Nitride E‐Phase
Authors: Batsanov S. S. , Kopaneva L. J. , Lazareva E. V. , Kulikova I. M. , Barinsky R. L.
Published: May 2005

A review of the works, in which the E‐phase of boron nitride had been obtained under various physical treatments, revealed that in all cases during the formation or isolation of the E‐phase the sample can be impurified with oxygen. An X‐ray spectral study of crystalline E‐phase obtained in the present work proved it to be a solid solution of the type BN1 − xOx containing B‐B bonds.
Processing of Trinitrotoluene‐Water Emulsions
Authors: Teipel Ulrich
Published: May 2005

When disposing of trinitrotoluene (TNT), the TNT‐melt must be pre‐treated. One possibility is to emulsify the melt in water after the TNT has been dismantled from the explosive charge. Production of these emulsions can be accomplished using emulsifying machines based on the rotor‐stator principle, e.g., ring gear dispersing machines or colloid mills. Droplet size reduction results from the normal and tangential stresses applied to the droplet as it is subjected to laminar or turbulent flow fields.

Knowledge of the droplet size and droplet size distribution of the dispersed phase is important to determine the quality of an emulsion and the emulsification process. In this paper, results from the discontinuous production of TNT‐water emulsions are presented. In addition, the use of laser diffraction spectrometry for analyzing TNT droplet size is described.
Decomposition of Composite Explosives Containing Ammonium Nitrate by transient adiabatic gas compression
Authors: van Niekerk Albert P. , Brower Kay R.
Published: May 2005

The decomposition products of emulsion explosives and of other composite explosives containing ammonium nitrate, such as ANFO, were investigated. The compounds were thermolyzed at high temperature and pressure on the microsecond and millisecond time scales by adiabatic gas compression. It was found that the first step in emulsion decomposition is pyrolysis of the oil to form reactive intermediates like Hċ and CH3ċ. These reactive species are oxidized by the decomposition products of ammonium nitrate in a later sequence of reaction steps.
Gun Propulsion Concepts. Part I: Fundamentals
Authors: Klingenberg G. , Knöchel H. , Maag H.‐J.
Published: May 2005

Modern gun propulsion techniques are driven by the desire to increase muzzle kinetic energy as a means to enhance weapon lethality, reduce costs, increase reliability, and improve vulnerability. In recent years, a significant part of research and developmental activities has been focused not only on conventional solid‐propellant and novel liquid‐propellant gun propulsion techniques but also on advanced concepts, particularly those offering substantial performance increase. High performance can be achieved by pure electric systems(coil or rail gun) as well as by combining chemical propulsion either with gasdynamic principles (light gas gun or ram accelerator) or with electrothermal techniques (hybrid gun). Part I of this paper deals with the fundamentals of projectile acceleration techniques. The objective is to provide the basis for understanding gun technology and to lay the basis for assessing present and future developments.
The effect of elastomeric liners on high‐pressure liquid propellant combustion oscillations
Authors: Vosen S. R. , Carling R. W. , Rychnovsky R. E. , Griffiths S. K. , Renzi R. F.
Published: May 2005

Liquid propellants are currently being investigated as an alternative to solid propellants in advanced gun designs. The use of liquids may provide advantages in the areas of safety, cost and performance. One area of concern in liquid propellant gun designs is the presence of large pressure oscillations: oscillations of ± 50% of the baseline pressure have been observed. These oscillations may result in a degradation of performance and reliability. The source of pressure oscillations and possible mitigation schemes are being studied in the Sandia Liquid Propellant Injector/Combustor. In this research device, the effect of acoustic liners on pressure oscillations in a high‐pressure (128 MPa) liquid propellant spray combustor is studied for a hydroxylammonium nitrate‐based propellant. In this study we investigated the effects of orientation and coverage fraction of elastomer liners on pressure oscillation reduction. Results for a range of elastomer/steel liner combinations are presented. along with an acoustic model and a correlation the data. The results indicate that: (1) linears can reduce oscillations by approximately three order of magnitude,(2) the reduction in pressure oscillation is independent of the placement of liners relative to the propellant flow, and (3) the magnitude of the oscillations can be correlated with the acoustic properties of the wall material.
Investigation on interfacial bonding in HMX‐containing model propellant composite
Authors: Weishang Yao , Wenhui Wu , Zhanning Jia , Jianwu Dai , Huiming Tan
Published: May 2005

A series of novel bonding agents which comprise the structural features of hydantoin and isocyanurate derivatives have been developed. The mechanical properties of model propellant composite containing these novel bonding agents were determined. Wilhelmy plate and wicking methods were used to evaluate wetting properties of these new bonding agents, and the wetting properties were discussed in the respect of thermodynamics and dynamics. Combined with the results obtained from FTIR and XPS analysis, the interfacial bonding of these novel bonding agents with HMX was evaluated.
Detonation Studies with a Ballistic Range Camera
Authors: Held Manfred
Published: May 2005

With an appropriate test setup, the Hadland Photonics Ballistic Range Camera (SVR), designed primarily for exterior and terminal ballistics, can also be used very well for studying initiation events and analysing a variety of detonation phenomena. This paper discusses detonics experiments carried out with the Ballistic Range Camera explaining in detail the test setup and the analysis of the results. The ability of the camera system to superimpose up to 16 images on a single frame allowed particularly detailed examination of detonation propagation, velocity, corner turning distance and the non‐reacting radial zones.
Barrier‐Test
Authors: Held Manfred
Published: May 2005

This paper will explain a test configuration for the diagnostic of the shock wave attenuation of homogeneous and sandwiched inert materials, which measures the delay time between the detonation of a donor and an acceptor charge, as well as the detonation profile in the acceptor charge. Applying the double‐flash‐gap technique, the analyzed pressure levels render possible conclusions about the existence of divergent or convergent detonation waves.
Estimation of ammonium perchlorate in HTPB based composite solid propellants using Kjeldahl method
Authors: Ajaz A. G.
Published: May 2005

Kjeldahl method has been applied to determine the percentage of ammonium perchlorate (AP) in hydroxy‐terminated polybutadiene (HTPB) based composite solid propellants. It has been found that in pastes containing aluminium (Al) it is important to eliminate all the Al before starting the actual reaction (distillation). The results obtained are in the range of ±0.05% for pastes with and without Al whereas the range is ±0.02% for pure AP. End points are confirmed using pH meter.
Comparative brisant characteristics of some classes of industrial emulsion explosives
Authors: Odintsov Victor V. , Pepekin Vitaly I.
Published: May 2005

The four types of mixtures consisting of the two bases (aqueous solutions of ammonium nitrate and ammonium dinitroamide) and the two additions (hollow glass microballoons and gunpowder) are considered in this work. On the base of thermodynamic computations of an ideal detonation and accompanying processes (shock and rarefaction waves) there were obtained not only the dependences of detonation parameters on addition quantities to mixtures, but the pressure versus particle velocity diagrams, too, which in comparison with Hugoniots relatively soft (water) and hard (aluminium) substances allowed to determine values of pressure in the shock waves being produced in surroundings nearby the end‐wall and lateral surface of a charge. It is proposed to characterize the brisant effect of an explosive by a value of relative brisance which is calculated as percentage ratio of pressures of shock waves generated in surroundings under the same conditions by detonation products of the given explosive and the standard one. It is shown that the brisant effect of the new emulsion explosives is comparable and even can exceed that of TNT of maximal density. It is shown as well that the brisant ability of industrial emulsion explosives can be raised by 60 and more percents by replacing ammonium nitrate with ammonium dinitroamide and hollow glass microballoons with powders being obtained as a result of military industry conversion and utilization of munitions.
Radiation curing of AP/HTPB‐based energetic composites. I. Effect on physico‐mechanical properties
Authors: Dedgaonkar V. G. , Navle P. B. , Shrotri P. G.
Published: May 2005

The use of gamma radiation has been successfully demonstrated as a powerful tool for curing of formulations of ammonium perchlorate and hydroxy‐terminated polybutadiene. This is not possible by conventional methods. The porosity observed in the composite is attributed to the shrinkage of matrix localized around surface of AP particles which creates voids in the bulk. Occurence of shrinkage is in the interphase zone and is due to excessive crosslinking of polybutadiene caused by radiolytic products of AP. Incorporation of toluene diisocyanate and ferric acetyl acetonate showed loss of radiation induced porosity and increase in density, tensile strength and elongation.
The Diffusion of Deterrents into Propellants Observed by FTIR microspectroscopy — Quantification of the diffusion process
Authors: Vogelsanger Beat , Ossola Bruno , Brönnimann Ernst
Published: May 2005

The interior ballistic performance of propellants can be significantly improved by the application of deterrents. However the diffusion of the deterrents from the surface into the propellant grains during long‐time storage may significantly reduce the propellants shelf life.

The diffusion of different types of deterrents into single‐ and double‐base propellants was investigated by Fourier Transform Infrared (FTIR) Microspectroscopy. The observed diffusion phenomena were explained sufficiently well by the 2nd Fickian diffusion equation. The determined diffusion coefficient values ranged between 10−17 m2/s and 10−14 m2/s at 71 °C. Polymeric deterrents were found to diffuse about one order of magnitude slower than deterrents of small molecular weight in the same propellant matrix. The diffusion velocities of the deterrents investigated increased by about 2 orders of magnitude between single and double base propellants. The changes in the interior ballistic behaviour caused by long‐time storage could be correlated with the obtained deterrent diffusion coefficient values. The results of this study are in good agreement with the very few data about the solventless diffusion process of deterrents published before.
Equations for Predicting Cookoff Ignition Temperatures, heating times, and violence
Authors: Victor Andrew C.
Published: May 2005

This paper presents a simple closed‐form equation that can be used to predict autoignition behavior of energetic materials (EM) over a very wide range of heating rates. In many situations, this equation can be used in place of computer‐based numerical methods to calculate munition cookoff ignition temperatures and heating times.

A simple model for predicting the violence of slow cookoff reactions that is also presented, matches small‐scale test data and demonstrates the elements that must be present in an a priori formulation of the problem.
The Relationship between BAM Friction and Rotary Friction sensitiveness data for high explosives
Authors: Wharton R. K. , Chapman D.
Published: May 2005

In this short paper we report the relationship between friction sensitiveness data for high explosives obtained using the BAM friction and Rotary friction test methods. Although both methods can be used in evaluating safety in transport, in other hazard assessments only the BAM test is specified. The results of this study could therefore have significance in reducing the burden of additional testing in those cases where Rotary friction data are already available.
Modification of Pyrotechnic formulations to aid recovery, recycling and demilitarization
Authors: Akhavan J. , Grose I. , Rabin S.
Published: May 2005

Following the International Treaty held in London and Oslo in 1972 and its amendment in Paris in 1992 on banning the dumping of hazardous and toxic waste at sea, large stockpiles of unwanted munition are now awaiting disposal. Public awareness, environmental concern and legislation are preventing the disposal of this explosive waste by landfill, detonation and open pit burning. One solution to this dilemma is to recover the waste from the containers and recycle or dispose of the waste in an environmentally sensitive manner.

Preliminary investigations have been conducted at Cranfield University in developing explosive compositions which can be safely recovered and recycled. Pyrotechnic compositions were prepared containing water soluble binders and pressed into pellets. Performance and sensitivity tests were carried out on the pellets. Inclusion of water soluble binders into pyrotechnic compositions did not have any detrimental effect on their performance. However, there was a 33% reduction in the Figure of Insensitiveness (F of I) in all cases except for the composition containing Dextrin. This had a similar F of I to the control pyrotechnic composition. The pellets containing Dextrin were immersed in water. 97% of the pyrotechnic components were successfully recovered from the water by filtration and recrystallization. The recovered components were recycled into new pyrotechnic compositions which performed just as well as the original composition. The results from this preliminary investigation show that recovery and recycling of pyrotechnic components is feasible for compositions containing water soluble binders.
Rocket Propellants with Reduced Smoke and High Burning Rates
Authors: Menke Klaus , Eisele Siegfried
Published: May 2005

Rocket propellants with reduced smoke and high burning rates recommend themselves for use in a rocket motor for high accelerating tactical missiles. They serve for an improved camouflage on the battle field and may enable guidance control due to the higher transmission of their rocket plume compared to traditional aluminized composite propellants.

In this contribution the material based ranges of performance and properties of three non aluminized rocket propellants will be introduced and compared to each other. The selected formulations based on AP/HTPB; AP/PU/TMETN and AP/HMX/GAP/TMETN have roughly the same specific impulse of ISP = 2430 Ns/kg at 70:1 expansion ratio. The burning rates in the pressure range from 10–18 MPa vary from to 26–33 mm/s for the AP/HTPB propellant, 52–68 mm/s for the formulation based on AP/PU/TMETN and 28–39 mm/s for the propellant based on AP/HMX/GAP. With 58% and 20% AP‐contents the propellants with nitrate ester plasticizers create a much smaller secondary signature than the AP/HTPB representative containing 86% AP. Their disadvantage, however, is the connection of high performance to a high level of energetic plasticizer. For this reason, the very fast burning propellant based on AP/PU/TMETN is endowed with a low elastic modulus and is limited to a grain configuration which isn't exposed too much to the fast and turbulent airstream. The mechanical properties of the AP/HMX/GAP‐propellant are as good or better as those of the AP/HTPB propellant. The first one exhibits the same performance and burn rates as the composite representative but produces only one fifth of HCl exhaust. For this reason it is recommended for missile applications, which must have high accelerating power together with a significantly reduced plume signature and smoke production.
Fast electrochemical Detection of Nitro‐ and Aminoaromates in Soils and Liquids
Authors: Krausa Michael , Doll Johannes , Schorb Klaus , Böke Winfried , Hambitzer Günter
Published: May 2005

The land sites of former explosives factories as well as troop exercise areas are frequently contaminated by 2,4,6‐Trinitrotoluene (TNT). As decontamination approaches, a direct on‐site measurement is necessary for a risk estimation. In contrast to ordinary analytics done in laboratories the employed methods are required to be fast and inexpensive. Additionally, they should be highly selective and sensitive. Up to now cyclic voltammetry is seldom used as an electrochemical method in the sensoric field. The presented new sensorsystem for the detection of TNT based on cyclic voltammetry fulfills the demands mentioned above.
Development of Gas Generators for Fire Extinguishing
Authors: Ebeling Hans , Schmid Helmut , Eisenreich Norbert , Weiser Volker
Published: May 2005

Gas producing materials are widely used in military or space applications as solid rocket and gun propellants. The chemical formulations of these propellants cannot be directly transferred to other applications as their product gases are optimized on high power, producing high amounts of CO and toxic trace constituents not acceptable in industrial applications.

Beneath small scale applications in inflating bag boats or ejecting pilots of aircrafts etc. the gas generators for airbag inflation became a standard equipment of cars and improved safety of drivers and passengers substantially.

Recently, systematic investigations started to realize the idea of using gases or aerosols produced by solid energetic or pyrotechnique materials for fire extinguishing. The actually introduced chemical gas generator formulations are based on the experience of pyrotechnics and solid propellants. Sodium azide and nitrocellulose containing mixtures cover most requirements on mass products. Despite their high level of technical development both formulations exhibit strong disadvantages.

The work reported considers organic formulations for fire extinguishing, which produce gases composed of N2 and CO2. The gasgenerants described consist of non‐toxic chemicals including fuel, oxidant, catalyst and cooling agent for thermal process control. The formulations show higher gas output per mass, can be recycled environmentally friendly and are of low costs. The results comprise thermochemical properties governing the time dependent gas output, characterization of the constituents and trace species of the product gas, safety and stability aspects. From selected gas generants the following data were measured: Estimation of thermal stability using DSC methods and mass‐loss tests; Pressure/time curves in the ballistic bomb; Rate of product gases by means of gaschromatography.
Thermal Analysis of Ammonium Dinitramide Decomposition
Authors: Löbbecke Stefan , Krause Horst H. , Pfeil Achim
Published: May 2005

The new energetic material ammonium dinitramide (ADN), NH4N(NO2)2, has been investigated with regard to its thermal properties and decomposition behavior. Thermal decomposition of ADN is observed after complete melting at 91.5 °C. The main decomposition pathway is based on the formation of NH4NO3 and N2O followed by the thermal decomposition of NH4NO3 to N2O and H2O at higher temperatures. Side reactions forming NO2, NO, NH3, N2 and O2 are described and a mechanism for the acid‐catalized decomposition of hydrogen dinitramide, dissociation product of ADN, is proposed.
Investigation of Slow‐Propagation Tungsten Delay Mixtures
Authors: Shachar Elie , Gany Alon
Published: May 2005

The burning characteristics and reliability of slow‐propagation tungsten delay mixtures (characteristic time 38–42 s/in) were studied experimentally by using various mixture compositions and tungsten particle sizes. Thermal analysis showed that potassium perchlorate is vital to initiate the reaction. Gravimetric analysis indicated that during the reaction overall mass loss of the delay mixtures did not exceed 5% compared to their initial mass. A mixture containing a tungsten powder of 6–8 μm was found to have the lowest effective activation energy, facilitating good ignition and burning zone propagation. The results of this study were successfully used to design a tiny delay which exhibited reliable ignition, burning and propagation characteristics under extreme conditions.
Plate Velocities for Asymmetric Sandwiches
Authors: Held Manfred
Published: May 2005

For the prediction of the plate velocities of asymmetric sandwiches, a simple equation basing only on the momentum law will be presented, which is easier to use than the formula given in the literature. It predicts nearly the same results or the deviations are smaller than the experimental scatters. Practical calculation examples are presented for the users.
Influence of Specific Surface Area of Aluminium Powder on the reactivity of aluminium/ammonium perchlorate composition
Authors: Rajendran A. G. , Kartha C. B. , Babu V. V.
Published: May 2005

Aluminium/ammonium perchlorate (40/60 wt.%) is a pyrotechnic composition widely used as an igniter charge for small calibre rocket motors. Five different types of aluminium powders with specific surface area varying from 0.52 m2/g to 6.00 m2/g have been studied to evaluate the influence of specific surface area on the ignition characteristics of the charge. While the peak pressure varies from 35.5 ksc to 54.5 ksc (0.30 g in 48.0 cm3 vol.), the corresponding time to Pmax varies from 11.2 ms to 1.6 ms showing higher reactivity of the mix with increase in aluminium surface area. This order of reactivity agrees with the order of reactivity determined from the DTG curves of the metal oxidation by comparing the peak height to half width ratio. However, the total gas generated by all the charges is approximately the same and the difference in peak pressure is caused by the difference in the rate of reaction and after about 30 ms all the compositions exhibit the same order of temperature and pressure. The charge has got an ignition temperature of about 640 K and the ignition is preceded by the exothermic decomposition of ammonium perchlorate. The activation energy varies from 92.2 kJ/mol to 127.6 kJ/mol and the corresponding pre‐exponential factor from 9.7 × 106 min−1 to 7.1 × 109 min−1 and they exhibit the kinetic compensation effect with an isokinetic temperature of 647 K.
An HPLC Method for Analysis of HNIW and TNAZ in an explosive mixture
Authors: Persson Birgitta , Östmark Henric , Bergman Helena
Published: May 2005

This paper presents a general HPLC method for qualitative and quantitative analysis of mixtures of explosives. The method has successfully been tested on the following explosives: RDX, 2,4,6‐TNT, 2,4‐DNT, HMX, PETN, Tetryl, HNS, TNAZ and HNIW. The method permits a nine component explosive mixture analysis in less than 10 minutes. For HNIW and TNAZ the detection limit was less than 5 ng.
AM1 study of ammonium 3‐nitro‐1,2,4‐triazole‐5‐onate (ANTO)
Authors: Cheng‐Wei Chang , Yeong‐Ming Wong , Te‐Chuan Chang , Cheng Chen
Published: May 2005

The geometrical structure of ANTO investigated by using AM1 semiempirical MO calculation shows that there are four distinguished intermolecular hydrogen bonding in the ANTO molecular/ionic system. The binding energies of NTO−/NH4+, NTO−/H2O and NH4+/H2O are −230.516 kcal/mol −136.671 kcal/mol and −14.664 kcal/mol, respectively. The charge densities show the deprotonation ability of various nitrogen's of NTO− ion, that result corresponds to some other's early study.
Accelerated Aging of Plateau Burn Composite Propellant
Authors: Oyumi Yoshio , Kimura Eishu , Nagayama Kiyokazu
Published: May 2005

Effects of accelerated aging at 60 °C on combustion characteristics, thermal decomposition, and mechanical properties of high burn rate composite propellant were studied in this paper. Although less change in burn rate was observed until aging period of two weeks, approximately 7% decrease was obtained at a pressure range from 9 MPa to 14 MPa after 32 weeks aging. The pressure range of the plateau‐mesa burning was shifted to higher pressure region by the aging. Although heat of decomposition measured by DSC decreased only 2% in the value, activation energy of thermal decomposition decreased 11%, from 133.3 kJ/mol to 119.5 kJ/mol. Increased CO2 and decreased HCN were also observed in the gaseous product distribution. Iron catalyzed processes involving AP and binder decomposition products were altered with a time of aging and it might generate the plateau burning pressure range shift. The sample kept 32 weeks, however, did not show any significant changes in mechanical properties.