Lead azide density

Type of lead azide density (g/ml) Sample Thickness (in.) Gas pressure Responses produced Average dose to lead azide (J/g) ... 

Lead azide Density (g/ml) Pulse width ( tsee) Initiation threshold (kbar)... 

Lead azide is manufactured by reaction of sodium azide with either lead nitrate or lead acetate. It is a white crystalline solid, insoluble in cold water and stable on storage. It is very sensitive to friction and impact and has a velocity of detonation, when pressed to a density of 3-8, of4500 ms 1. 

Two crystallographic forms of lead azide are important, the ordinary alpha form which is orthorhombic and the beta form which is monoclinic. The densities of these forms are 4-71 and 4-93 respectively. It was for many years believed that the beta form is the more sensitive to friction and impact and accounted for detonations which have occurred in the manufacture and handling of the substance. It is now known that the beta form is in fact no more sensitive than the alpha. Even the alpha form, when present as large crystals, is very sensitive and conditions can arise (particularly when the formation of the lead azide is controlled by diffusion effects) where spontaneous detonation occurs. Although with modern knowledge these hazards can be avoided, pure lead azide is nevertheless a dangerous compound and is now made only for military purposes. 

Lead styphnate is a poor initiating explosive which when dry is very sensitive to friction and impact, to electrostatic discharge, and to flame. Its main use is as an additive to lead azide to improve flame sensitiveness (see p. 101). When pressed to a density of 2-6 g ml-1 it has a velocity of detonation of4900 m s l. 

The writer (unpublished results) was able to initiate Lead Azide pellets of ca 2.5 g/cc density with oxy-acetylene detonations. However ca 1.2 g/cc PETN pellet could not be initiated under these conditions. Gordeev et al [Nauchn-Tekhn Probl Goreniya Vzryva (1965) p 12 CA 64 1894 (1966)] succeeded in initiating liquid mixtures of tetranitromethane (TNM) and benzene with stoichiometric methane-oxygen detonations. For 1.5 vol parts of TNM 1 vol p of benz the initial pressure, P0, of the detonating gas mixture had to be greater than 2 atm to initiate the liquid. Initiation delays decreased as P0 increased delays were 350, 10 0 psec for P0 of 2, 12 24 atm. For 4 1 by vol TNM/benz initiation of the liquid was observed for Po>0.7 atm. At Po 0.7 atm the initiation delay for this liquid mixture was 70 jusec... 

AZOTIDRATO Dl PIOMBO (Lead Azide-LA) o Acido di piombo, Pb(N3)2, is described by Belgrano (Ref 31, pp 439—49). Its props are Density (max) 4.79, Explosion Temperature... 

EXAMPLE THE DENSITY OF LEAD AZIDE PRESSED AT lOpOOpsI IS ABOUT 2.9 g/cm2... 

Density of AN based expls can be controlled by the addn of vermiculite) K) R.L. Wagner et al, "Investigation of British Service Lead Azide , EDS (Explosives Development Section) Rept 457248, PicArsn, Dover, N.J. 

Resorcinol nitrates readily to the trinitro compound, yellow prisms from water or alcohol, m.p. 175.5°. Styphnic acid is more expensive and less powerful than picric acid. Liouville67 found that styphnic acid exploded in a manometric bomb, at a density of loading of 0.2, gave a pressure of 2260 kilos per sq. cm., whereas picric acid under the same conditions gave a pressure of 2350 kilos per sq. cm. It did not agglomerate to satisfactory pellets under a pressure of 3600 kilos per sq. cm. It is a fairly strong dibasic acid, and its salts are notably more violent explosives than the picrates. Lead styphnate has been used to facilitate the ignition of lead azide in detonators. 

A Swiss patent of 1932 to Stettbacher nr covers the conversion of PETN into a plastic mass by means of 10-30% of a fluid nitric ester such as nitroglycerin or nitroglycol. It states that a mixture of 80% PETN and 20% nitroglycerin is a plastic mass, density 1.65, which does not separate into its components and which is suitable for loading shells and detonators. For the latter purpose it is initiated with 0.04 gram of lead azide. 

The true density of lead azide is 4.8, but the loose powder has an apparent density of about 1.2. 

Hexamethylenetriperoxidediamine is almost insoluble in water and in the common organic solvents at room temperature. It detonates when struck a sharp blow, but, when ignited, bums with a flash like nitrocellulose. Taylor and Rinkenbach 63 found its true density (20°/20°) to be 1.57, its apparent density after being placed in a tube and tapped 0.66, and its density after being compressed in a detonator capsule under a pressure of 2500 pounds per square inch only 0.91. They found that it required a 3-cm. drop of a 2-kilogram weight to make it explode, but that fulminate required a drop of only 0.25 cm. In the sand test it pulverized 21/ to 3 times as much sand as mercury fulminate, and slightly more sand than lead azide. It is not dead-pressed by a pressure of 11,000 pounds per square inch. It is considerably... 

Lead Azide of Different Density , ZhFrikl-Mekhan i TekhnFiziki 1961, No 4, pp 99—101 118—27 [Joint Intelligence Bureau, Division... 

Primary explosives include mercury fulminate [Hg(ONC)2, melting point 160°C with explosion, density 4.2], lead azide [Pb(N3)2, density 4.0], basic lead styphnate (lead trinitroresorcinate), diazodinitrophenol, and tetrazine (a complex conjugated nitrogen compound, melting point 140 to 160°C with explosion). Most priming compositions consist of mixtures of primary explosives, fuels, and oxidants. 

Through irradiation the optical density of azides increases as shown by Roth J I8] and Wiegand [119]. Tiie experimental facts supported the hypothesis at colloidal metal was produced by irradiation of lead azide and talliuin azide. oUoidal disorder can be created by radiation, Lead produced by photodecom- Sitiorr is reactive and can form some products on exposure to air. Thus basic ad carbonate was found lead azide irradiated with X-rays [120, 121J. Lead de expands along one crystallographic direction under the action of X-rays 122) and nitrogen in the form of N2 can be trapped by the irradiated lattice... 

Colloidal lead azide is obtained by adding at 25°C 4% aqueous solution of sodium azide to a small excess of lead nitrate solution. Tlie precipitate is fih trated and washed with water and dried. Its density under 3000 kg/cm pressure is 2.77 g/cm (as compared with 2.93 g/cm of crystalline lead azide). 

Polyvinyl Alcohol Lead Azide (PVA Lead Azidej. Polyvinyl alcohol was used instead of dextrin in Germany [2]. In the U.S.A. it is in use in OUn Mathson Corporation [1311. The addition of 3% PVA makes lead azide of better initiating properties, higher density and an easier inflammability than dextrinated lead azide [1],... 

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