PBXW-115, an Extremely Insensitive Detonating Substance

摘要

The underwater polymer bonded explosives, PBXW-115 (Aust.), PBXN-111 and B2211, all have the same basic composition, viz., bimodal RDX (20 % by mass) , ammonium perchlorate (43 %) and aluminium (25 %) in a plasticised polyurethane binder. However, because the ingredients used in their formulations come from different sources and have their own characteristics (particle size distribution, shape, etc.), small but distinct differences in the properties of the three formulations can be seen. Nevertheless, the three PBXs are characterised by large critical diameters, large reaction zone length parameters and resistance to high-impulse shock and hazardous stimuli. An earlier review of the explosive hazard properties of PBXW-115 (Aust) and PBXN-111 established that PBXs based on the original formulation should qualify as potential fills for Insensitive Munitions (IM). However, whatever the benefit of such a qualification, it begs the question as to what is the appropriate UN Transport and Storage Hazard Division classification for ordnance filled with these PBXs. If, in fact, ordnance filled with PBXW-115 (Aust.) or PBXN-111 can be classified as HD 1.6 instead of a more restrictive HD 1.1 classification, then considerable savings can be made in the transport and storage of such ordnance. To address this, one needs to resolve two further questions: 'Can PBXW-115 (Aust.) and PBXN-111 qualify for classification as Extremely Insensitive Detonating Substances (EIDS).' and 'Do articles of ordnance filled with these PBXs have the potential to meet the criteria for UN Transport and Storage Hazard Division HD 1.6 classification.' This report presents a case to Support an EIDS classification for PBXW-115 (Aust.) and PBXN-111. It is based on results from experiments carried out by the French defence contractor, SNPE, on their formulation, B 2211; their work indicates B 2.