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8217803 
Journal Article 
Current trend of R&D in the field of high energy materials (HEMs) - An overview 
Singh, H 
2005 
15 
3 
120-133 
English 
Just as a creative force can be used for destructive purposes, a destructive force can also be tamed for constructive roles. High energy materials (HEMs) have been used in extracting ores, minerals, coal and for the construction of subways, airports, canals and harbours. Metal cladding, artificial diamond processing from graphite, rock compression and stone removal from the bladder of patient are other important applications of HEMs. Ti and Al react under explosive shock to yield new alloys suitable for Aerospace Industries. This manuscript presents an overview of the various HEMs used for civil, space and military applications. Site Mixed Slurry (SMS) and Site Mixed Emulsions (SME) are being used for mining. Smokeless powder and composite propellants based commercial explosives have also been used for many other commercial applications. RDX / HMX based shaped charges with copper / steel as cone material have been used for oil exploration. Solid fuels containing energetic materials can be used to produce heat energy at high altitude to warm food and water. Life saving devices like Pilot Seat Ejection, Canopy Severance System (CSS) use HEMs with varying solid loading 0.4 gm/meter to 300 gm/meter. HEMs are also used for riot control and non-lethal weapon (NLW). There are 65 explosive factories in India manufacturing around one million ton of civil explosives annually. Propellants, explosives and pyrotechnics are the main energy source for space and military applications. These days major focus is on the development of advanced solid propellants having higher energy (Isp), environment friendly combustion products and insensitivity. In the field of high explosives, high VOD, high thermal stability and insensitivity to shock, friction and impact are getting high importance. HNS, TATB etc. are used for high temperature applications (>350°C). RDX / HMX based compositions still find extensive use in view of high brisance power, stability, cost and processability. Cage compounds like ONC (octa nitro cubane) and CL-20 (HNIW) are being evaluated for specialized applications. Of late, insensitive HEMs (LOVA and LOVEX) are drawing high attention to minimize unintentional explosion. Energetic polymers like GAP, copolymers of BAMO are entering the domain of advanced systems. BAMO - IHF based co-polymers are fast emerging as an energetic thermo plastic elastomer for extruded composite propellants. High nitrogen content (HNC) materials are focal point of research. N5 + and N6 appear to be promising materials. N60 is expected to produce VOD of 17 km/sec with detonation pressure of 200 GPa. It is hoped that ADN and HNF based propellants with GAP and Al shall produce Isp of more than 300 seconds. In addition to higher energy, superior mechanical properties assume high importance due to extension of flight domain of modern aircrafts and air launched missiles.