Military explosives properties

In this chapter the explosives employed are discussed their actual application is described in Part III. The most important properties of the commonest military explosives are listed in Table 3.1. 

Pentaerythritol tetranitrate (PETN) (3) is a powerful explosive which exhibits considerable brisance on detonation (VOD 8310 m/s at = 1.77 g/cm ). It is the most stable and least reactive of the common nitrate ester explosives. The relatively high sensitivity of PETN to friction and impact means that it is usually desensitized with phlegmatizers like wax and the product is used in detonation cord, boosters and as a base charge in detonators. Pentaerythritol tetranitrate can be mixed with synthetic polymers to form plastic bonded explosives (PBXs) like detasheet and Semtex-IA. A cast mixture of PETN and TNT in equal proportions is known as pentolite and has seen wide use as a military explosive and in booster charges. The physical, chemical and explosive properties of PETN commend its use as a high explosive. 

Nitrations giving a complex mixture of products are not useful in organic chemistry or for the synthesis of explosives, and so, another route to the required product should be considered which is more selective. Although it is acceptable for commercial explosives to contain a mixture of aromatic nitro compounds, military explosives are almost always single compounds with well-defined physical properties. 

Adolph and Cichra synthesized a number of polynitroperhydro-1,5-diazocines and compared their properties with the powerful military explosive HMX. A type of Mannich condensation was used to form the 1,5-diazocine rings the condensation of ammonia and methylamine with formaldehyde and bis(2,2-dinitroethyl)nitramine (46) forming diazocines (47) and (48) respectively. 1,3,3,7,7-Pentanitrooctahydro-1,5-diazocine (47) is A-nitrated to 1,3,3,5,7,7-hexanitrooctahydro-l,5-diazocine (52) in near quantitative yield using mixed acid. 

Both 1,3-DNB and 1,3,5-TNB have been used for their explosive properties (HSDB 1994). 1,3-DNB has been suggested as a possible substitute for the explosive TNT (HSDB 1994). 1,3-DNB has been used as a camphor substitute in nitrocellulose, a compound used in explosive and propellants (HSDB 1994 Sax and Lewis 1987). 1,3-DNB was manufactured during both world wars as a component in the explosive roburite (ERA 1976). 1,3,5-TNB has been classified as a high explosive and has been used in military and commercial explosive compositions (Merck 1989 Sax and Lewis 1987). A more powerful explosive than TNT, 1,3,5-TNB is less sensitive than TNT to impact (Merck 1989). 1,3,5-TNB has also been used as an explosive for oil wells and mining operations (OHM/TADS 1991). 

KL) Anon, "Military Explosives", TM 9-1300-214/TO 11A-1-34 (1967). Chapter 5. Properties and Tests of High Explosives Sensitivity to Frictional Impact (pp 5 1 to 5-3) Sensitivity to Friction (5 3 to 5-6) Sensitivity to Frictional Impact (5-6) Sensitivity to Heat and Spark, which includes Explosion Temperature Test (5-6 to 5-9) Sensitivity to Initiation (5-9) Stability Tests, which include 75° International Test, 100° Heat Test, Vacuum Stability Test and Potassium Iodide—Starch Test (5 9 to 5-15) Brisance Tests which include Sand Test, Plate Dent Test and Fragmentation Test (5 15 to 5-18 and Fig 5 13 on p 5-19) Initiating Value (5-18 5-20) Sympathetic Detonation (5-20 to 5-21) Power which includes Heat of Explosion Test, Ballistic Pendulum Test and Trauzl Lead Block Test (5-21. to 5-24) Blast Effect (5-24 to 5-27) Cratering Effect (5-28 5 29) and Munroe-Neumann Effect (5-29 to 5 35)... 

The requirements of a military explosive are very stringent and very few explosives meet all the characteristics necessary to make them acceptable for military applications. In order to determine suitability of an explosive for military applications, explosives are first investigated for properties described in the previous section followed by their study from the point of view of volatility, toxicity, hygro-scopicity and density which are considered of paramount importance because of field conditions and optimal performance requirement. 

Trinitrotoluene (TNT) was the most commonly used conventional military explosive during the twentieth century. Although it had been used extensively in the dye industry during late 1800s, it was not adopted for use as a military explosive until 1902, when the German army used it to replace picric acid. TNT was first used in warfare during the Russo-Japanese War (1904-1905). The US Army began its use in 1912. After an economical process was developed for the nitration of toluene, TNT became the chief artillery ammunition in World War I (1914—1918). The most valuable property of TNT is that it can be safely melted and cast alone or with other explosives as a slurry. 

This book is split into six well-defined chapters Salient Features of Explosives, Status of Explosives, Processing and Assessment of Explosives, Propellants, Pyrotechnics, and Explosive and Chemical Safety. Further, the book includes an exhaustive bibliography at the end of each chapter (total references cited are more than 1000). It also provides the status of HEMs reported mainly during the last 50 years, including their prospects for military applications in the light of their physical, chemical, thermal and explosive properties. The likely development areas for further research are also highlighted. Accidents, fires and explosions in the explosive and chemical industries may be eliminated or minimized if the safety measures described in this book are implemented. 

The substance possesses quite uncommon and valuable explosive properties. It is more powerful than tetryl, and considerably less sensitive to impact (as sensitive as picric acid). However, its acidic properties limit its use to a great extent. In this respect it resembles picric acid. Even so ethylenedinitramine, under the name of Haleite, has been accepted in the United States as a military explosive. During World War II, production in that country was carried out by the method outlined above according to eqn. (17)... 

Jr, Properties of Explosives of Military Interest, PATR 1740, revised by O.E.Sheffield (April 1958XU)(Expls props of standard military explosives) 72)H.Taube A.G.Maddock, edits,"Chemistry of the Coordinate Compounds, Pergamon Press, NY,vl(1958X638 pp)... 

Explosive Properties Explosion Temperature 300° (Ref 4) Impact Sensitivity 20 to 35 cm vs 25 cm for tetryl 110 cm for TNT, using 2 kg wt (Ref 4) Power, by Lead Block Expansion, 380-400 cc vs 290 cc for TNT or 131 8% TNT (Ref 4) Reactivity - the nitro group in the 3 position is readily replaced Stability claimed to be as stable as TNT (Ref 4) but not found so by others. See also Ref 8 Uses. TeNAns was used in Germany in initiating and other expl mixts (Refs 3 7) but later was found to be too reactive and too sensitive for military or com) application. No information at our disposal about its uses in other countries... 

S.Travers, MAF 25, 167 73(195 l)(Remarks on the above paper of Muraour Aunis) 29) W. Guttmann, Sprengtechnik 1952, 47-52(Theory of proplnt burning) 29)H.Muraour G.Aunis, MP 35, 286-301(1953)(Laws of burning of colloidal proplnts. Historical review of work done in France between 1884 and 1953 Included are 50 refs) 29a)A.O.Pallingston M.Weinstein, PATR 2005(1954)(Method of calcn of interior ballistics properties of proplnts from closed bomb tests) 29b)Anon, "Military explosives,... 

Hexanitro-N,N -diphenylurea (hexanitrocarbanilide or st/m-dipicrylurea)120 may be prepared by the nitration of carbanilide (sym-diphenylurea) in one, in two, or in three stages. It is of interest because of its explosive properties and because it supplies one way in which benzene may be converted into an explosive which is valuable both for military and for civil uses. Carbanilide may be prepared by the interaction of aniline and phosgene but is most conveniently and economically procured by heating aniline and urea together at 160-165°. 

B.M. Dobratz LLNL Explosives Handbook Properties of Chemical Explosives and Explosive Simulants, Lawrence Livermore Laboratory UCRL-52997 March (1981). Military Explosives Army Technical Manual TM9-1200-214, Sept. (1984). 

From these calculations, an essentially complete overview of the explosion properties and characteristics of shock wave action on barriers was obtained for several new and also for several standard explosive materials for comparison (Figs. 9.36, 9.37, 9.38 and Tab. 9.13). The results which were obtained suggest that in a wide range of their initial states (porosity, inert binders), the new explosive materials TKX-50 and MAD-X1 possess better explosive properties and shock wave action on practically every compact barrier which was considered, in comparison with standard explosive materials including the military explosive RDX. The large number of the calculated results which were obtained can be used to study the influence of different factors on the explosion and shock wave action of new explosive materials. Furthermore, some of these results can then be used to plan experiments to confirm the predicted properties. 

Composed of potassium nitrate, charcoal, and sulfur. Had been for 550 years the only military explosive available as a propellant now replaced by smokeless powder. For properties and present military and industrial uses, see Black Powder (With Potassium Nitrate), Blasting Powder A. 

Properties This is one of the most, if not the most powerful explosive. It is claimed to be more sensitive than picric acid and therefore not suitable as a military explosive in shells.28... 

LOX and AN Explosives. The explosive properties of various commercial and military expls are given in tabular form. The expls include TNT, Dynamite, high-AN-NON-NG, LOX and water compatible types. Such properties as heat capacity Cv> heat of explosion Q, absolute temp T, pressure p, and number of molecules/kg are given Ref Cook (1958), 306-21... 

TNAD is a powerful explosive with excellent properties and stability. Its use in military explosives is moderate, but will show remarkable use in the future—as it grows in popularity. It has essentially the same density as RDX, and only a slightly lower calculated detonation velocity. TNAD has a melting point of 232-234 Celsius, and is used in propellant compositions, and... 

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