Detonation rate mercury fulminate

At the Chemisch-Technische Reichsanstalt [56] the figures given on p. 148 were found for the rate of the detonation of mercury fulminate, pressed into detonators ... 

The rate of detonation of mercury fulminate (according to Patry [22])... 

Properties White, pulped fibers, having a nitrogen content of 13.2-13.5 per cent, only partly soluble in ether-alcohol, completely soluble in acetone. Deteriorates under heat, but is stable in moist condition. In fiber form it is a high explosive gelatinized, it is a low-order explosive. The dry fiber can be detonated with mercury fulminate. Dry guncotton can be used as initiator for the detonation of wet guncotton. Rate of detonation (13 per cent nitrogen) 6300 m/sec. (d = 1.7). 

According to Kast and Haid [55] the rate of detonation against the density of mercury fulminate is related as follows ... 

A mixture of mercury fulminate containing 10% of KC103 detonates at a density of 3.16 with a rate of 4090 m/sec. 

The rate of detonation of a thin film of lead azide (0.1-0.5 mm thick) is 2100 m/sec (Bowden and Williams [101]). Lead azide is less sensitive to impact than mercury fulminate, but drop test figures quoted by various authors differ widely. Some of them report a negligible difference between the two, while others state it is considerable (e.g. that azide requires 2-3 times the height of drop necessary to explode fulminate). On the other hand, when mixed with pulverized sand lead azide is more... 

Fig. 75. The relation between the density and the rate of detonation, and sensitiveness to initiation by mercury fulminate of chlorate explosive [80].

Perchlorate explosives, like chlorate explosives, can be compressed to a high density, but the detonation at a high density is difficult. This is illustrated by a graph published by the French Commission on Explosives (Commission des Substances Explosives) (Fig. 75) [80] which shows how the rate of detonation and the amount of mercury fulminate required for detonation varies with density. 

The stoichiometric mixture (mentioned above) was found to be very sensitive to priming. It was detonated by a primer as weak as 0.6 g of mercury fulminate. The rate of detonation, or more precisely of explosion, was variable (this is typical for liquid explosives) 1300-2000 m/sec. Expansion in the lead block was found to be 85 (picric acid = 100) which is the same value as that of dinitrobenzene (88). 

Fhie detonation of an explosive is almost always effected by the detonation of >re sensitive explosive, of which a small quantity is placed in juxtaposition with first, and fired by mechanical shock, fuses, or electrical devices. Ordinary iission cap composition contains a mixture of mercury fulminate, potassium rate and antimony sulphide to which powdered glass may be added, in order attain increase of sensitiveness. The caps for detonators are of pure copper, cylindrical in shape, closed at one end, and charged with an intimate mixture 5 iaer cent, mercury fulminate and 15 per cent, potassium chlorate. Detonators nade in ten sizes, numbered consecutively, and contain 0.3, 0.4, 0.54, 0.65, o.8, x. 5, 2.0, 2.5, or 3 g. of the detonating mixture. 

When a 0.5 gram sample of tetryl is heated at a rate of 20°C per minute, ignition occurs between 190°C and 194°C. If the temperature of a sample is held at 180°C ignition occurs in 40 seconds. The minimum primary charges necessary for reliable detonation of tetryl with mercury fulminate is 0.20 to 0.29 grams and with lead azide is 0.025 to 0.10 grams. Tetryl containing 60 percent water cannot be detonated by a commercial detonator. Shock sensitivity as measured by the gap tests are summarized in table 8-30. 

Raiko (Army) or Raisansuigin (Navy) Thunder Mercury . Mercuric Fulminate, Hg(ONC)2 mw 284.65, N 9.84% white to gray pdr, d 4.43, mp—decomp or detonates without melting Brisance by Sand Test—ca 55% TNT Expin Temp 210° in 5 secs Impact Sensitivity, BurMinesApp, 2-kg wt—5cm Power by Trauzl Test—51% TNT Rate of Deton 5000 at d 4.0 (AMCP 706-177, listed as Ref 8, p 201). Used straight by the Japanese in Instantaneous Fuzes, in Blasting Caps and in mixture called Bakufun (Ref 1, p 25 Ref 5, p 369)... 

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