Chapter 14: The Properties of Detonating Compositions Prepared from Submicron KClO₄ and TiH₂

A new kind of THKP was prepared by combining submicron potassium perchlorate made by the Spray Flash Evaporation (SFE) process with titanium hydride. Spray Flash Evaporation is based on flash evaporation to manufacture nanoparticles. The solvated product is nebulized in a chamber, which is maintained under vacuum, thanks to an atomization nozzle. The sudden fall of pressure induces a flash evaporation of the solvent and then crystallization of the product in the form of nanosized particles. This process was used on potassium perchlorate in order to produce nanosized particles of this product. This new type of potassium perchlorate prepared by SFE shows a particle size ranging from 50 to 400 nm. With this submicron sized potassium perchlorate, a better oxidation of titanium hydride was observed and also a transition to detonation in the THKP. This detonation transition was noted when the THKP is placed in a small diameter tube (3 mm) in loose powder. In the same time, the detonation velocity of this type of THKP increased to a value of approximatively 1250 m/s with a porosity of 86%. In comparison, micron sized potassium perchlorate in THKP tested in the same condition, no transition to detonation was observed and sometimes combustion stops. The sensitivities of THKP prepared with submicron sized potassium perchlorate are relatively high with an impact sensitivity of 44.7 J, a friction sensitivity of 192 N and an electrostatic discharge sensitivity of 34.7 mJ. THKP mixtures prepared from submicron potassium perchlorate can be classified as low-sensitivity primary explosives.