Impact sensitivity of liquid explosives

MagyKemFolyoirat 7(8), 346-52(1956) (Initiation of expln of Amm Perchlorate with Cr20j-Ti02 catalysts) 19) P.E. Skidmore D.E. Thompson, "Development of an Improved Method for Determining Impact Sensitivity of Liquid Explosives , ABL Rept ABL/X-10 (1957) 19a) J.E. Sin-... 

Measurement of Impact Sensitivity of Liquid Explosives and Monopropellants... 

Johansson and co-workers (7, 8, 9) have shown that heat transfer from a compressed spherical bubble does not increase the temperature of its liquid surface sufficiently to account for the impact sensitivity of liquid explosives the high sensitivity of nitroglycerin is postulated as arising from the fact that small droplets are readily formed by the impact and ignited by the compressed air. Bolkhovitinov (1) postulated crystallization of the liquid under the impact pressure, with the phase transition causing the temperature increase which causes explosions. Bowden (3) favors the adiabatic compression of gas bubbles combined with the dispersion of the explosive into fine particles as the mechanism for initiation by mechanical impact. 

Table VIII. Effect of Liquid Nitrogen on the Impact Sensitivity of Primary Explosives [57] ... 

A. V. DUBOVIK and V. K. BOBOLEV. Sensitivity of Liquid Explosive Systems to Impact, Nauka, Moscow, 1978. 

Extremely explosive, heat- and shock-sensitive as liquid or vapour [1], During determination of the impact-sensitivity of the confined material, rough handling of the container caused ignition. The material should only be handled in small quantity and with great care [2]. 

Nitromethane is usually not sensitive to heat or mechanical impact, exhibiting stability to some extent. The starting materials for the production of nitromethane are adequately abundant and inexpensive, and nitromethane itself is a noncorrosive chemical that can be safely transported or handled, thus, it is an important component for the preparation of liquid explosives. 

Organic derivatives of 5-azidotetrazole have been reported by Friedrich [99]. They are more stable and less sensitive than the metallic salts. The methyl and ethyl derivatives are very strong igniting explosives. Ethylene tetrazylazide, that forms an oily liquid, possesses extraordinary brisance and is easily ignited by spark and flames. It easily gelatinizes nitrocellulose [1,99]. Impact sensitivities of 5-azido-l-methyltetrazole and 5-azido-l-picryltetrazole in comparison with the copper salt are summarized in Table 8.19 [79]. 

The cyanide is a friction- and impact-sensitive explosive, and may initiate detonation of liquid hydrogen cyanide. Other heavy metal cyanides are similar. 

Mechanical impact on a road surface on to which liquid oxygen had leaked caused a violent explosion [1], Anecdotal evidence that there have been several like incidents is given [2], Mixtures of asphalt and liquid oxygen were shown to be impact-sensitive on the small scale, but on the larger scale a detonator was necessary to initiate mild explosion of liquid oxygen on a layer of asphalt [3], Oil,... 

Addition of liquid air to ether in a dish caused a violent explosion after a short delay. Previous demonstrations had been uneventful, though it was known that such mixtures were impact- and friction-sensitive. 

Explosives Sensitivity Data. Card-gap and projectile sensitivity, data are presented by Watson (Ref 1) for a wide variety of expl compns tested at the USBurMines laboratories in more or less standard test geometries. The results of both tests are in good agreement in that they provide the same sensitivity ordering fbr different subclasses of expls. Least sensitive were homogeneous liquids that did not exhibit a tendency, to undergo low-velocity detonation, AN-FO (Ammonium Nitrate-Fuel Oil), and most cast military expls. Of intermediate sensitivity were pressed and powdered military expls, cast Pentolite, permissible and nonpetmissible water-based expls, and one commercial two-component expl. The most sensitive were permissible and nonpermissible Dynamites and expls susceptible to low-velocity detonations Refs I) R.W. Watson, 1 Card-Gap and Projectile Impact Sensitivity Measurements, A Compilation , USBurMines Information Circular 1C 8605(1973)... 

Picatinny arsenal (PA) impact apparatus The sample which is placed in the depression of a small steel die-cup and then capped by a thin brass cover, is used in this test. The value of minimum height at which at least one out of ten trials results in explosion gives impact sensitivity. In the case of liquids, it is filled in a die-cup and tested in a manner similar to solids. 

W.H.Rogers "The Sensitivity of Explosives to Bullet Impact , OSRD 5745(1945)(The rept deals with "ordinary cast HE s, with ordinary pressed HE s, with some sluminized expls and with some liquid expls. A German method of testing is briefly described on p 11) 9)Anon, "Ordnance Proof Manual , OPM 7-24, Aberdeen PG, Md(1945), p 5 10)Ohart(1946), 31 ll)Anon,... 

The sensitiveness to impact of solid, liquid, or gelatinous explosives is tested by the fallhammer method. The samples of the explosives are... 

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