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Subgroup A Energetic Materials Team, SG/A (EMT), develops and maintains standards that are relevant to all life-cycle phases of ammunition/weapon systems. STANAG 4147 is the standard regarding chemical compatibility of explosives with munition components, and is a document of prime importance. Currently the 3rd edition of STANAG 4147 has been sent out for ratification. Several aspects of the assessment of compatibility are addressed in this paper, including test conditions (temperature and duration), the mixing ratio of explosive composition and contact material, and sentencing criteria. Future standard development may benefit from on-going research providing experimental data, and possible directions are indicated.

This poster describes the work done within the Category B joint research project under the European Defence Agency (EDA) on Future Flare Compositions [1]. Contributing members were Finland, Germany, United Kingdom and the Netherlands. The program was aimed to identify the technology gaps that apply to countermeasures against future IR/EO threats to flying platforms. The focus has been on new advanced flare compositions against the above mentioned threats. Also rapid design and analysis tools for spectral countermeasures for new threats were developed. Work defined were a literature study of the current state of the art, a workshop on spectral countermeasures with the focus on modeling and rapid design, next generations countermeasures by a selection of concepts and the manufacture of test flares, and full scale trials to test for suitability and correlate modeling results.

Subgroup A Energetic Materials Team, SG/A (EMT), develops and maintains standards that are relevant to all life-cycle phases of ammunition/weapon systems. STANAG 4147 is the standard regarding chemical compatibility of explosives with munition components, and is a document of prime importance. Currently the 3rd edition of STANAG 4147 has been sent out for ratification. Several aspects of the assessment of compatibility are addressed in this paper, including test conditions (temperature and duration), the mixing ratio of explosive composition and contact material, and sentencing criteria. Future standard development may benefit from on-going research providing experimental data, and possible directions are indicated.

This poster describes the work done within the Category B joint research project under the European Defence Agency (EDA) on Future Flare Compositions [1]. Contributing members were Finland, Germany, United Kingdom and the Netherlands. The program was aimed to identify the technology gaps that apply to countermeasures against future IR/EO threats to flying platforms. The focus has been on new advanced flare compositions against the above mentioned threats. Also rapid design and analysis tools for spectral countermeasures for new threats were developed. Work defined were a literature study of the current state of the art, a workshop on spectral countermeasures with the focus on modeling and rapid design, next generations countermeasures by a selection of concepts and the manufacture of test flares, and full scale trials to test for suitability and correlate modeling results.

Analyses of internal ballistics and criteria for reaction propagation in nonelectrical tube explosive lines were performed based on explosive loading density, average particle size, and typical geometry using an approach based on heat transfer and decomposition kinetics in the explosive particles in quasi steady state. The results indicate the existence of a critical or maximum average explosive particle size for a given explosive loading density beyond which sustained propagation may cease. Large variations usually exist in the explosive loading density, so that fine particle sizes below 20 μm are preferable. Fine particle size also may increase the adhesion to the inner tube wall for mitigation of powder migration problems. Computer simulations of detonating end tip to nondetonating end tip transfer were performed using the CTH hydrodynamic code developed by the Sandia National Laboratories. Preliminary results indicate that the hot gas from the detonating end tip is more effective for initiating pyrotechnics in the nondetonating end tip and that a larger gap between the end tips is essential for the success of hot gas initiation

Post explosion residues (PER) are residues from pyrotechnic compositions or explosives that are generated during an explosion. In the recent past SEM/EDX was used several times to analyze PER from pyrotechnic compositions. The results from these studies suggest that there might be a difference in morphology and composition of pyrotechnic residues formed at different levels of confinement. Also because of general thermodynamic principles it is believed that at higher levels of confinement the final pressure and temperature during the explosion is probably (but not necessarily) higher, eventually resulting in smaller and more spherical particles and a more homogeneous elemental composition. If there is a relation between morphology and composition of pyrotechnic residues and the level of confinement at which these are formed, it would be possible to draw conclusions about the conditions at which pyrotechnic residues were formed and the kind and construction of the device used. This may aid forensic scientists not only in the determination of the original explosive composition, but also of the explosive device. To perform controlled experiments with pyrotechnic charges at, at least, two pre-set levels of confinement a test vessel was built by TNO Defence, Security and Safety. For this study, three different flash powder compositions and black powder were selected. The generated residues were sampled on collecting plates and Nucleopore filters connected to a pump system in the immediate vicinity of the venting area for further analyses by SEM/EDX and XRD. From the results it follows that in the pressure range studied, the level of confinement seems to have a minor effect on the features of the generated residue particles. Because passive sampling by means of collector plates seemed doubtful and because the number of experiments had to be limited it is impossible to draw definitive conclusions. In addition to the level of confinement several other variables may affect size, shape and composition of pyrotechnic residues. More experiments and improved sampling methods are necessary to determine what variables have the most pronounced effect on shape size and composition of pyrotechnic residues.