Polymer-bonded secondary explosives

In this paper, a review of the available literature on physical and explosive properties of explosive compositions containing a secondary explosive and a polymer binder (PBX) is presented. The review focused on an analysis of the properties of compositions containing mostly synthetic polymers. The review showed that, at the moment, the most commonly used composition is a hexogen-based explosive bonded with a chemically cross-linked hydroxylterminated polybutadiene. The use of energetic polymers in PBX compositions was observed only in the experimental systems tested on a laboratory scale. The most popular methods of forming compositions include pressing a previously phlegmatized explosive or chemical cross-linking of the composition in the projectile shell. Compositions which can be formed and reloaded using injection machines are known, but due to many limitations, the method is not widely used.

Towards Safer Primers: A Review

Primers are used to reliably initiate a secondary explosive in a wide range of industrial and defence applications. However, established primer technologies pose both direct and indirect risks to health and safety. This review analyses a new generation of primer materials and ignition control mechanisms that have been developed to address these risks in firearms. Electrically or optically initiated metal, oxide and semiconductor-based devices show promise as alternatives for heavy metal percussive primers. The prospects for wider use of low-cost, safe, reliable and non-toxic primers are discussed in view of these developments.

Crystal structure of the high-energy-density material guanylurea dipicrylamide

The title compound, 1-carbamoylguanidinium bis(2,4,6-trinitrophenyl)amide [H2NC(=O)NHC(NH2)2]+[N{C6H2(NO2)3-2,4,6}2]−(= guanylurea dipicrylamide), was prepared as dark-red block-like crystals in 70% yield by salt-metathesis reaction between guanylurea sulfate and sodium dipicrylamide. In the solid state, the new compound builds up an array of mutually linked guanylurea cations and dipicrylamide anions. The crystal packing is dominated by an extensive network of N—H...O hydrogen bonds, resulting in a high density of 1.795 Mg m−3, which makes the title compound a potential secondary explosive.

Study on the Nanocrystalline WC-10Co Hard Alloys Prepared by Mixing and Explosive Compaction

The nanocrystalline WC-10Co hard alloys with high density (97.5% T.D.) have been prepared by use of mixing and explosion compaction technology and the average crystalline size is less than 100 nm. The microstructure analysis shows that, the particle size of the mixing powders is less than 200nm and that of the explosive compaction billet is even fine about 100nm. If explosive speed of any explosive is either big or small, we can not get density billets because the initial density of mixing powders is too low. If using secondary explosive compaction process (low-speed explosive Ammonium Nitrate 280g + high-speed explosive TNT 200g), we can get about 97% (maximum density of 97.58%) of the theory density of bulk nanocrystalline WC-10Co hard alloys.