Explosives military materials

Explosive Mixture of Methanol-Water-Magnesium (or Aluminum). On the basis of theoretical ealens of heat of evolution -t the author concludes that mixts of Mg or Al with water or ales are potentially more powerful expls than the usual military materials with MeOH-Mg giving max gas evolution. The experiments were conducted in bombs or lead enclosures with Tetryl detonators to... 

Aluminum (or Magnesium)-MethanoI (or Water) Explosives. According to Shidlovskii (Ref l mixts of Al and HaO(2 3) or Mg and H20(1 1) are capable of combustion when subjected to intense heat. The Mg mixture can be detonated with a primer while the Al mixt cannot. The same investigator claimed (Ref 2) that on the basis of theoretical calcns of. he at evoln, mixt s of Mg or Al with HaO or ales are potentially more powerful expls that the usual military materials, with.Mg-MeOH giving the max gas evoln. The tests were conducted in bombs or lead enclosires with tetxyl detonarors to set off the mixts of powdered metal and the liquid. All mixts tested were found to be powerful expls with Mg-H30 being most sensitive to shock, while Al-HaO and Mg-MeOH were less sensitive and required a booster... 

Oxidizing Properties. Nitric acid is a powerful oxidizing agent (electron acceptor) that reacts violentiy with many organic materials (eg, turpentine, charcoal, and charred sawdust) (19,20). The concentrated acid may react explosively with ethanol (qv). Such oxidizing properties have had military appHcation nitric acid is used with certain organics, eg, furfuryl alcohol and aniline, as rocket propellant (see Explosives AND PROPELLANTS). 

Investigations in the field of shoek eompression of solid materials were originally performed for military purposes. Speeimens sueh as armor were subjected to either projectile impact or explosive detonation, and the severity and character of the resulting damage constituted the experimental data (see, e.g., Helie, 1840). Investigations of this type continue today, and although they certainly have their place, they are now considered more as engineering experiments than scientific research, inasmuch as they do little to illuminate the basic physics and material properties which determine the results of shock-compression events. 

The requirements of the US Armed Forces are described in Military Specification MIL A-166C (6 January 1975) entitled, Ammonium Picrate (Explosive D) It covers one grade of material, representing two classes with respect to granulation. Class 1 material (coarse) is intended for use in the press-loading of shells, while Class 2 (fine) is used for the manuf of Picratol and other compns. The requirements are as follows ... 

The preparation and properties of TNT are described in Chapter 3. Next to nitroglycerine, TNT is the most important sensitising constituent of commercial explosives. For such purposes it does not need to have the high purity demanded for the military product, but otherwise the material is identical. 

A major contribution from chemistry and chemical engineering has been the development of materials with important military applications. Chemists and chemical engineers, working with experts from areas such as electronics, materials science, and physics, have contributed to such developments as new explosives and propellants, reactive armor (a complex material with an explosive layer that can reduce the penetration of an incoming projectile), and stealth materials that reduce the detectability of aircraft by radar. 

Criminals and mentally disturbed or immature persons are both likely to be limited by the availability of materials and knowledge. In addition, criminals are quite likely to be more susceptible than the other groups to deterrence by visible and effective security measures. Thus, the first two groups — state-sponsored actors and non-state-sponsored terrorists — are the main threats on which explosives detection needs to focus. Unfortunately, this conclusion implies the need for detection of military, commercial, and improvised explosives and does not greatly help in narrowing down the issues. 

Large quantities of explosives are used every year. In the United States, for example, the annual consumption exceeds over 2 million tonnes. Most are used for commercial purposes and are ammonium nitrate-based formulations. There are less than a dozen chemical explosives that are manufactured in bulk quantities, and most of these were discovered in the 50-year period between 1850 and 1900. New explosives have been synthesized but optimization of the formulations takes decades and is very expensive. Consequently, any new material has to offer very significant advantages, either in terms of unique performance for military applications or in terms of cost and safety for commercial applications. 

Military explosives are required to meet stringent criteria because apart from a requirement for high performance, the military needs to be able to safely store them for decades, transport them anywhere from the poles to the equator, handle them under battlefield conditions, and still have them fuUy functional. In addition, availability of raw materials, ease of manufacture, and cost are important factors. Most candidate explosive compounds do not meet all these requirements. 

Plastic explosives contain one or more of the explosives listed above, moulded in an inert, flexible binder. Because powders do not readily hold a shape and TNT is the only common melt-castable explosive, most of the explosive powders (RDX, HMX, PETN, 1,3,5-triamino-2,4,6-trinitrobenzene (TATB)) are plasticized to make a mouldable material, for example, C-4, Semtex H, PE4, sheet explosive. A variety of plasticizers are added, but the maximum level is usually 10-15% because most plasticizers are inert and would degrade explosive output. Plastic explosives were originally developed for convenient use in military demolitions but have since been widely used in terrorist bombs. For detection techniques that rely on vapour signatures, such as canine olfaction, it is worth considering that the plasticizer is much more volatile than the explosive component. 

Nitrolysis is a term originally used for the rupture of a N-C bond leading to the formation of the N-NO2 group. A prime example is the nitrolysis of the N-CH2 bonds of hexamine to form the important military explosives RDX and HMX. Nitrolysis is the most important route available to polynitramine energetic materials. 

Uses. To implode fissionable material in nuclear devices to achieve critical mass as a component of plastic-bonded explosives and solid fuel rocket propellants and as burster charges in military munitions. 

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