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Detonation nanodiamonds: problems and prospects. V.V. Danilenko Moscow vvdan@list.ru. Transient period in technology cycle of human civilization:. Microstructures → Nanostructures Microelectronics → Nanoelectronics
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Detonation nanodiamonds:problems and prospects V.V. Danilenko Moscow vvdan@list.ru
Transient period in technology cycle of human civilization: • Microstructures → Nanostructures Microelectronics → Nanoelectronics • What determine Decisions and Priorities? • Market only or Scientific Forecast ? • No market ↔ no production ?
Detonation parameters and phase diagram of nanocarbonV.V. Danilenko. Fiz. Gor. Vzryva. 2005, V. 41, N. 5. Detonation Amorphization Porosity
Scheme of explosive technology Inert gas Ice or watershell Explosives: Dry product collector + Hexogen TNT Wet product collector Further acid purification
DND structure and Properties - DND nanoparticle - unique combination of superhard inert diamond core and highly active porous amorphous cover on core. - DND - polydispersional raw material due to differ conditions for DND synthesis in volume of detonation charge
Structureof nanodiamond particle Spherical shape d = 2 - 8 nm Surface functional groups and adsorbed water Diamond core amorphous carbon, sp3 → sp2 structuries 0.4 - 1 nm
Synthesis conditions and DND qualityConditions of synthesis: - Characteristics of a charge (HE structure, geometry, weight, initiation). - Environment surrounding a charge (gas, water, ice, metal, mix).Quality of the DND: - The maintenance of the DND in detonation carbon (the attitude sp3/sp2). - A degree of DND particles connectivity in strong units. - Quantity of not carbon impurity.
Influence of Detonation Conditions on the Quality of Nanodiamonds Increase in Temperature, pressure, time, carbon concentration
DND Applications • sp3/sp2:Nanodiamonds-graphite……… 20 – 75 % Pure DND………………. ……… > 95% • Optimal contents in materials – 0,5 – 5% • Applications: Motor oil, lubricates, electroplates, resin, polymers, alloys, ceramics, polishing, biology, medicine…
DND: paradoxical situation • Good research of properties, • it is found many applications, • possible market of DND is estimated in $300 bls. • Nevertheless market is not created. • Many small manufactories are closed finally or temporary (low profitableness). Why?
Cost price of DND production in USA 100 kg /14 hours (24 t / year)
Market of DND is not created on following causes: • - no investors(big corporation or government) • - very high priceof DND • - dependence synthesis condition – DND qualityis poorly investigated (synthesis without ashes) - optimum DND qualityfor each application is not found - DND – polydispersion raw material – need treatments - industrial technologies of gas-phase purification, fractionation, strong units dispersion, modification are not developed - as result - industrial samplesof materials and products with DND are not created and not tested.
Proposals • Use for industrial production of DND: • charges ≥ 20 kg, explosion under water in close pool (in heavy metal cover), laser initiation; • utilization of old ammunition under water in close pool; • Production three group of diamond powder: • - DND – 5 – 100 nms; • - micropowders – 0.1 – 600 μm; • - grindpowders – 0.6 – 1 mm.
Conclusion • A number of not solved technological and marketing problems, braking industrial production and applications DND is analyzed. • It is offered: • - to synthesize simultaneously the DND and abrasive diamond powders by explosion of the big weight charge in a heavy metal cover under water in closed pool; • - utilization of old ammunition under water in closed pool; • V.V. Danilenko. Superhard Materials. 2010, N5