A Concept and the Use of Negative Explosives

Dr Takeo Shimizu 

ABSTRACT:

In general, a pyrotechnic composition consists of an oxygen donor such as KNO3, KClO3, or KClO4, etc., an oxygen donee such as organic resin and some other inert substances. When substances, CaCO3, Al2O3, SiO or CaSO4, etc. are contained in it, they are regarded as an inert substance, because they are full of oxygen and cannot be more oxidized. This type of explosive deflagrates with oxidation reaction and could be called “positive explosives”. However, when some substances, Mg, Al or Si, etc., which have a very large reduction capacity, the inert substances change to active ones. This type of explosives, which consist of Mg, Al or Si, etc., plus a substance which is thought to be inert in conventional explosives, is defined here as “negative explosives”. With the oxygen donee, Mg was concerned as a representative case, because it is very popular and has the largest reduction capacity; it burns even sand or earth. About 50 types of negative mixtures were listed as samples. Their characteristics were examined by several tests. Ignition and burning properties were tested on the ground by using black match. Ignition temperatures were obtained from a heating test in a glass tube. Illuminating capacities were measured by burning consolidated mixtures as a flare. Ballistic characteristics were examined by firing a projectile with a small mortar by using granulated mixtures for the propellant charge. The results were discussed and a proposal for use of negative explosives was made.


(SH1_011)


Download/Purchase Options :

You must be logged in to purchase or download articles.

Comments are closed.