In order to quantify the contribution of aerobic and

In order to quantify the contribution of aerobic and protein phosphatase inhibitor aluminum reaction contributing to blast and overpressure, aluminized RDX-based explosives were detonated under controlled conditions while varying the particle size and atmosphere [52]. Early-time reaction of aluminum acts to enhance the primary explosive blast, and this reaction is approximately half aerobic and half anaerobic (i.e. compositions by detonation products and/or nitridation), suggesting that very rapid early-time mixing occurs in explosive fireballs. It was found that particle size effects were surprisingly negligible over the range of 3–40 µm. The observation implies that conventional scaling laws for aluminum combustion provide less insight than previously assumed. The data of quasi-static pressures obtained in the time period from 5 to 10 microns after detonation have revealed that oxidation of aluminum is complete in the presence of 20% O2. However, in N2 environments, oxidation of aluminum only proceeds to half its theoretical maximum, except for the smallest particles (3 µm) for which oxidation was almost complete. Thus, oxidation of aluminum in aluminized explosives is robust in anaerobic environments. Therefore the simulation efforts cannot over-neglect the anaerobic channels, even though aerobic oxidation provides the greatest energy release. In the article by Nicolich et al., high-performance aluminized explosive compositions for high performance, high blast, low sensitivity explosive applications have been presented [53]. The compositions include Cl-20, HMX, RDX, or another material as the explosive ingredient, a binder system of cellulose acetate butyrate and bis-dinitropropyl acetyl and bis-dinitropropyl formal, and aluminum. The explosive is preferably pressable and or/mixable to permit formation of grains suitable for ordnance and similar applications including grenades, landmines, warheads, demolition, etc. It was found that the aluminum fully participated in the detonation of abovementioned explosive compositions, manifesting its energy into fully usable metal-pushing energy which is suitable for shaped charges, explosively formed penetrators, enhanced blast warheads, fragmentation warheads, multipurpose warheads, and so on. The aluminum is substantially reacted at two volume expansions of the expanding gas, and fully reacted prior to seven volume expansions of the expanding gas [53]. During the last couple of years, great efforts have been focused on the development of new kinds of weapons which are able to generate high blast and temperature effects, namely abovementioned thermobaric weapons. Also, a lot of research studies have intensely focused on the comprehension of thermobaric effects, in order to enhance or prevent it. The blast effect is mainly due to the ability of the detonation products to react with the oxygen of air. This phenomenon called afterburning substantially contributes to generate high pressure impulses, especially in confined spaces. This is the reason why metallic particles, mainly aluminum particles, are commonly used in thermobaric explosive compositions (TBX). In the light of the recent studies, in France (SME Center de Recherche du Bouchet) a novel enhanced-blast plastic-bonded explosive (EB-PBX) has been developed in order to generate enhanced blast effects [54]. This new composition has been called B2514A. The developmental stages of such a composition have been performed through different phases, within the domain of small scale trials to large scale ones. A specific methodology was used to examine and classify a large number of candidates. The most promising composition experimentally has been tested at large scale to characterize its ability to generate blast effects in comparison with PBX known for their blast effects [54]. The reaction of metal particles with the decomposition products of energetic materials like water, carbon oxides and nitrous gases plays an important role in many pyrotechnics. Often, air that is entered into the fumes can also burn the metal particles or other reaction products in rival. This may lead to additional heat release, radiation or other desired effects in applications like ducted rockets, aluminized rocket propellants, blast-enhanced explosives (SIBEX), incendiaries or countermeasure flares, etc. In order to investigate such reactions, Weiser et al. considered a composite RDX, including 5% paraffin mixed with particles of various reactive metals: aluminum (Alcan, Alex), magnesium, boron, coarse and fine silicon, titanium, and zirconium [31]. In the experiments, RDX with paraffin was investigated as the reference material. The pressed mixtures (as strands) were burned in a window bomb under air atmosphere and under pure nitrogen at 0.3 MPa. The combustion was investigated using a high-speed color camera, equipped with a macro lens and fast scanning emission spectrometers operating in the range of 300 nm-14 µm. The data were collected and analyzed to characterize different reaction zones, to identify the intermediate metal oxides and final reaction products and combustion temperatures of condensed particles and gaseous species (like water, and di-at. fuel oxides) formed during the transient combustion process as function of time and position [31]. In the study, the different temperatures of reacting surfaces, particles and reaction gas(es) were considered as main parameters to characterize the reaction of fuel particles with RDX and additional air. The results have been discussed in comparison to qualitative reaction kinetic and to thermodynamic equilibrium calculations with EKVI and ICT-Thermodynamic Codes. The study showed a kind of ranking according to different applications and the effect of air. In some cases the additional air resulted in a temperature increase of several hundred kelvin. However, this effect is not only affected by the chemistry of the filler but also by other factors, like the particle size (those are also discussed in the paper) [31].