Abstract:To study the influence of nanometer transition metals on the thermal decomposition of ammonium perchlorate (AP),three kinds of nanometer transition metals (Ni,Cu and Co) were prepared from an aqueous solution by reducing their corresponding metal salts. DTA was employed to test the thermal decomposition of AP in the nanometer transition metal/AP composite. Results indicate that the catalysis of nanometer Ni and Cu increases with the content of nanometer metals and the high and low temperature decomposition peaks have a tendency of overlapping together. The suitable content of nanometer metal Co powder in the composite presentes at about 5%,while the catalysis of nanometer metal Co results in the lowest thermal decomposition temperature of AP in the composite at about 288 ℃. The catalytic capability of nanometer transition metals accordes with the stabilization energy order of their complexes formed with NH₃ as a decomposed intermediate of AP: Co＞Cu＞Ni.

Abstract:The effects of nine nano metal oxides,including Co₃O₄，Fe₂O₃，Bi₂O₃，CuO，PbO，Al₂O₃，TiO₂,NiO and PbO/CuO,on thermal decomposition of HMX were investigated by PDSC,TG-DTG and iso-TG. The results show that the decomposition of HMX in solid phase before melting is advanced by the metal oxides,especially PbO,Al₂O₃ and TiO₂,and the endothermic melting peak of HMX mixed with PbO and Al₂O₃ even disappear entirely,owing to the compensation of exothermic decomposition in solid phase at pressure. Thermal decomposition of HMX in liquid phase at high pressure of 3 MPa is catalyzed by PbO,but not affected by Al₂O₃ and TiO₂. The results of TG-DTG at lower heating rates and iso-TG under HMX melting temperature are in agreement with those of DSC in solid decomposition at ambient pressure. These results are advantageous to the identification of the different effects of nano and normal metal oxides. The catalytic decomposition of HMX by nano and normal metal oxides,including CuO,PbO,Al₂O₃ and TiO₂,were also characterized by the kinetic parameters obtained from isothermal and non-isothermal TG. The kinetic parameters obtained from isothermal TG are in agreement with those from non-isothermal. The catalytic effects characterized by means of kinetic parameters consist also with those by DSC and TG-DTG. The decrements of E_a values of the decomposition of HMX with three nano materials,except CuO,are more than that of those with normal materials.

Abstract:The catalysis of nano Cu powder on the thermal decomposition of HMX and RDX was investigated by using DSC,PDSC and TG-DTG. The results show that thermal decomposition of solid phase for HMX and liquid phase for RDX is accelerated apparently due to the nano Cu powder. The solid phase thermal decomposition temperature of HMX decreases 25.5 ℃ when the mass ratio of HMX with nano Cu is 1：1. The liquid phase decomposition temperature of RDX accelerates from 239.1 ℃ to 220.9 ℃. The decrease of exothermic enthalpy is due to the dilution and dispersion function of the nano Cu powder.

Abstract:The boron powder with diameter from 0.3 μm to 3.4 μm was made with planet ball-milling. The particle size of boron powder was characterized by SEM and Laser Particle Size Analysis. DTA and TG were used to characterize the thermal behavior of the 50/50-B/AP composition with different boron particle size. The results show that thermal behavior of boron composition is affected obviously by the particle size of boron powder. The smaller the particle size of boron powder,the greater the apparent decomposition heat and mass loss of the 50/50-B/AP composition. Compared with the original boron(d₅₀=3.40 μm),heat release of fine boron(d₅₀=0.30 μm) is increased from -19.7 J·g^-1 to 556.2 J·g^-1.

Abstract:Boron composition particles coated with LiF,Al,Ammonium perchlorate(AP) respectively were prepared by methods of solvent-nonsolvent,solvent evaporation,extraction, and experimental propellants with these particles were also made. IR，SEM were used to characterize their structure and forms,and DTA and TG were used to study the thermal behaivors. Results indicate that coating makes water on boron composition surface decrease and the thermal characteristic of boron composite and the propellant improve. Compared to pure boron/AP mixture,the apparent decomposition heat and loss of weight of AP/nano Al composite mixture increases from -19.7 J·g^-1 to 1799.1 J·g^-1 and from 52% to 69.02%,respectively. In comparison with propellant with pure boron powder,the apparent decomposition heat of propellant with boron composition increases 12.6%.

Abstract:Aluminium (Al) nanopowder has been shown to possess unique thermal behaviour and to enhance the performance of some energetic materials (EM). However,Al nanopowder has a high reactivity with water,which causes "aging" of Al nanopowder,and consequent reduction in its effectiveness in EM compositions. Water adsorption and desorption is a particular concern,since the aging reaction of Al nanopowders may be related to the water adsorbed on its surface. The thermodesorption of adsorbed gases on nanometer-sized aluminium powders was investigated using Thermogravimetry (TG) and Thermogravimetry-Fourier Transform Infrared-Mass Spectrometry (TG-FTIR-MS). The results show that the Al nanopowder studied contains 12 mass % of adsorbed gases. Desorption of water and carbon dioxide was observed by FTIR and MS. The kinetic parameters for the desorption of the adsorbed gases were determined using variable heating rate and isothermal studies. The activation energies of desorption obtained from the various methods are compared.

Abstract:The in-situ dispersion polymerization in the presence of nano- aluminium was used to prepare the nano-aluminium microcapsules by styrene (St) as monomer and ethyl alcohol as reaction media without oxygen and water,and effect of surface treatment was studied. The results show that the sorts and amounts of surfactant have great influences on the morphology of nano-aluminium/PS microcapsules. After treated with Span-80 or PEG under ultrasonic irradiation,in-situ dispersion polymerization on the surfaces of nano-aluminium is initiated in region containing rich monomer and initiator. When nano-aluminium absorbing PEG and primary nucleus absorbing PVP reach dynamic balance，W_PEG=20.0 wt% St,the nano-aluminium microcapsules with smooth surfaces and well dispersion can be prepared, which can encapsulate most nano-aluminium.

Abstract:Cu nanoparticles were prepared by solution-reduction method and Cu/CNTs(carbon nanotube) composite particles were prepared by CVD (Chemical Vapour Deposition) method. The nanoparticles were characterized by SEM,TEM,XRD and FT-IR. DTA was employed to test the catalytic effects of these nanoparticles on thermal decomposition of AP. The results indicated that Cu nanoparticles made the peak temperature of high temperature decomposition of AP decrease 130.2 ℃ and the peak temperature of low temperature decomposition of AP decrease 35.1 ℃,Whereas Cu/CNTs composite particles made the peak temperature of high temperature decomposition of AP decrease 126.9 ℃，and the peaks of low and high temperature decomposition of AP overlap,proving that CNTs promote the catalytic effect of Cu nanoparticles on the thermal decomposition of AP.

Abstract:The natural graphite was used as main body to prepare super-fine FeCl₃-GIC by means of ration-blended method. The layer structure of samples was investigated by X-ray diffraction. The results show that stage structure is 3 and 4 stage co-existed,and primary element of product is 3 stage. The lattice distance of 3 stage FeCl₃ -GIC is 0.945 nm. The magnetization intensity and magnetic susceptibility of FeCl₃-GIC were measured with vibration magnetometer. With energy dispersion spectrometer,the concentration change of carriers was shown. The charge transfer model was set up and GIC′s conductive mechanism was analyzed. Moreover,the property of super-fine FeCl₃-GIC interfering infrared imaging apparatus was tested. The results show that product can shield photoelectricity instrument at the military far infrared frequency.

Abstract:The characteristic of infrared extinction for 8 species of α and γ-nanometer aluminas was studied by dispersing in a smoke chamber and pressing potassium bromide tablet with a Fourier Transform Infrared Spectrometer. The results show that nanometer alumina possesses a good infrared extinction characteristic,and the maximum mass extinction coefficients of nanometer alumina aerosols are 1.798 m²·g^-1 and 1.940 m²·g^-1 in 3-5 μm and 8-14 μm bands. Moreover,the infrared transmission rates of γ-nanometer alumina are lower than that of α-nanometer alumina,and the infrared extinction of nanometer alumina is enhanced when the specific area increases or diameter decreases.

Abstract:Nano Fe₃O₄ was prepared by chemical co-precipitation and characterized by XRD. Different smoke compositions were made using micron Fe₃O₄,micron TiO₂,nano TiO₂/Fe₃O₄ and nano Fe₃O₄ as oxidizer and their burning property and infrared extinction capability were studied by DTA and infrared transmission percentage test. The results show that the exothermic peak of the smoke composition with nano Fe₃O₄ accelerate 28 ℃ compared to that of smoke composition with micro TiO₂,whereas its burning rate and infrared extinction capability are improved. The results indicate that the smaller particle size of oxidizer as well as the faster burning rate of smoke composition is,and the infrared extinction capability decrease with the increase of oxygen content in oxidizer.

Abstract:The shock sensitivity of sub-micron explosive was studied by small-scale gap test and slapper initiation test; and the shock wave was low pressure-long pulse in the small-scale gap test,and high pressure-burst pulse in the slapper initiation test. The explosive is safe when motivated by a generic environmental force,i.e. low pressure-long pulse and it is sensitive when motivated by special environmental force,i.e. high pressure-burst pulse. Moreover, the shock sensitivity decreases with the reduction of explosive particle size when ignition is a dominant process in the course of shock wave initiation; but oppositely,the shock sensitivity increases when detonation buildup is dominant.

Abstract:The ultrafine RDX explosives are prepared by the method of pulse ram-type pulverization,and the RDX particles with 4.020 μm are obtained at 120 MPa impulse pressure and RDX/water in the mass ratio of 1：5. The effect of water propotion,impulse pressure and cycle times are discussed as well,and the results indicate that the particle size of RDX decreases with increase of water proportion and impulse pressure. And to some extent,the particle size of RDX decreases slightly with increase of cycle times.

Abstract:The recrystallization of AP was carried out using supercritical CO₂ as the anti-solvent and acetone as the organic solvent for AP． The effects of the main parameters including temaperature,initial concentration of the solution, the final pressure and hold time after the pressurization on the gas anti-solvent(GAS) recrystallization process were studied． AP particles (30-40 nm) with narrow size distribution are obtained at 10 MPa,40 ℃and 35 kg·h^-1． The results show that the intensity of liquid onflow have a great influence on AP average size and morphological characters in GAS，and AP crystals develope from the nuclei to sphericity,polyhedron,needles,and whiskers　in GAS．

Abstract:The mass effect of protective medium on the yield of nanometer diamond was studied to improve the yield of ultrafine diamond. The protective medium was water and the double protective medium (solid-state and liquid medium) was applied in the experiment. The results show that the influence of water protective medium mass on the yield of UFD is notable, and the optimum mass of water given in the experiment is 8.8 L.The application of the double protective medium can further improve the yield of ultrafine diamond.

Abstract:Ultrafine Graphites (UFG) prepared by explosive detonation in the water protective medium was studied. The advantages of the technology using water as protective medium are convenient and safe and low cost technology. Moreover,UFGs have high purity and concentrate granule. UFGs obtained from TNT,RDX and graphite have the medium size of 9.3 nm and the surface area of 1116.2 m²·g^-1.

Abstract:The magnetite particles (Fe₃O₄) were successfully prepared by an oxidation-precipitation method. XRD technique was used to characterize the size of the sample. It indicates that the average size of particles in diameter is about 50 nm with a narrow size distribution. To explore the new application of magnetite nanoparticles, thermal compatibility between magnetite nanoparticles and explosives in common use including potassium perchlorate (PP), 2,2′, 4,4′,6,6′-hexanitrostilbene(HNS), hexadydro-1,3,5-trinitro-1,3,5-triazine (HMX) and 3,5-dinitro-2, 6-dipicrylaminopyridine (PYX) was determined by DSC technique. The results show that Fe₃O₄ powders with 50 nm in diameter have fair compatibility with PP or PYX,but poor compatibility with HNS and bad compatibility with HMX.

Abstract:Nanotechnology techniques may be used to influence,or establish,certain properties of materials such as the oxide coating on aluminum particles. It is shown how control of the melting of the coating on aluminum particles in a mining explosive helps control the split of the total energy released into shock energy,that supports the detonating shock wave and heave energy,that heaves the overburden off the ore body. By appropriately choosing the thermal characteristics of the coating on the aluminum particles the total energy may be split into the most advantageous proportions.

Abstract:Nano-composite energetic materials research were reviewed including the preparation technologies of sol-gel method,solvent/non-solvent method,energetic ball milling method and porous metal/filler method. The experiment examples,detailed peculiarity and mutual relations of the methods were described. It is concluded that nano-composite energetic materials researches can unfold a novel way for energetic materials and improve their safety during storage and application compared to nano powders. The nano-composite energetic materials preparation theory and practice should be promoted to enrich and develop the energetic materials.

Abstract:The latest development in the preparation of nano-scale combustion catalysts used in solid propellant was reviewed. Advantages and disadvantages of solid phase reaction method, electrolysis method,hydrothermal reaction method,precipitation method,hydrolysis method,sol-gel method and micro-lacteous method were stated and compared. The problems existed in the preparation study of nano-scale combustion catalysts used in solid propellant,the research directions of the preparation study and emphases in the future were also pointed out.

Abstract:The properties and application of ultrafine explosive powder including TATB,RDX,HMX were reviewed. And research trend of ultrafine explosive powder was also proposed such as particle active protecting technology,particle dispersing technology and acting mechanism to obtain ultrafine explosive powder and formulas with actual application value.

Abstract:

Abstract:

Abstract:

Abstract: