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HMX/Cu composite particles are prepared by the electroless plating method. The size, morphology and phase of particles are analyzed by SEM and XRD. And the DSC is applied to study their thermal decomposition characteristic. The results show that the composite particles coated with Cu of 80 nm in diameter have obvious catalysis effect on solid phase decomposition of HMX. The percentage of the prophase decomposition heat increases from 2. 37% to 97. 29% . On the other hand, the thermal decomposition peak moves to the low temperature of 35. 53 °C and the rate slows down. Especially, the thermal decomposition of HMX/Cu become to be very intense at the heating rate of 15 °C /min. Compared with HMX, the apparent activation energy of HMX/Cu is decreased by 33. 16 kJ/mol. It is advantageous to the thermal decomposition of nano HMX/Cu through adding a moderate amount of O2. Moreover, "Effect of spatial distribution" of catalyst is presented based on the analysis of nanometer Cu catalyst mechanism. [ABSTRACT FROM AUTHOR]

Nano octahydro-1, 3, 5, 7-tetranitro-1, 3, 5, 7-tetrazocine (HMX) was prepared by the use of pulverized machine HLG-50. The size distribution was traced by the nano laser particle size analyzer, and the particle size was characterized by SEM. The contaminants were detected by the use of FT-IR, Raman spectra, XRD and ICP-AES. The thermal decomposition of nano HMX was described by the TG/ DSC simultaneous thermal analyzer. The friction, impact and shock sensitivities were tested to indicate the stability. The result shows that the diameters of the most particles are less than 100 nm and the impurities in the product were absolutely few. The peak temperature of its thermal decomposition decreased a little compared with the raw materials. The friction sensitivity reduced by a large margin, particularly the impact and the shock sensitivities decreased 132.6% and 60.0%, respectively. The stability increased so much that there would be a good application. By the way, the mechanism of reduced sensitivity was discussed. [ABSTRACT FROM AUTHOR]

Submicron hexanitrohexaazaisowurtzitane ( CL-20 ) is prepared using HLG-50 pulverized machine. The laser particle size analyzer and SEM are used to characterize the particle size, size distribution and morphology of sample. The polymorph and purity of CL-20 particles are characterized by Fourier transform infrared spectrometer, laser Raman spectrometer, XRD and HPLC, respectively. The TG/DSC simultaneous thermal analyzer is used to study the thermal decomposition of CL-20. The shock sensitivity of samples are studied. The results show that CL-20 particles are pseudo-spherical with an average particle size (d50) of 210 nm. The polymorph of submicron CL-20 is consistent with that of the raw ε-CL-20. Compared with the raw CL-20, the thermal decomposition peak temperature of the submicron CL-20 is decreased slightly, and the shock sensitivity of the submicron CL-20 is considerably reduced by 53. 1% . That implies the obvious reduction in the shock sensitivity of CL-20. [ABSTRACT FROM AUTHOR]

The conventional way takes a long time to determine the uniformity of absorbent powders in blend procedure, which is an obstacle to automation and continuation of production process of solid propellant. Near-infrared (NIR) analysis is proposed to solve that problem. A micro NIR spectrometer is used to collect the spectra of absorbent powders that are stirred continually, and the moving block of standard deviation (MBSD) algorithm is utilized to quantitatively analyze the difference between spectra of absorbent powders. The uniformity and endpoint are presented from the standard deviation-time curve. In addition, the accuracy of NIR analysis on the collected samples is confirmed through high performance liquid chromatography (HPLC). The results show that NIR analysis is efficient, eco-friendly and safe. It is feasible to apply NIR analysis to monitor the blend uniformity of modified double-base absorbent powders online and determinate the endpoint of blend process in real-time. [ABSTRACT FROM AUTHOR]

Different mass fractions of AlMg alloys are prepared by mechanical ball milling. AlMg/KMnO4 thermites are prepared by sonication dispersion method. These thermites could be an energetic material in the field of reactive materials and explosives. AlMg/KMnO4 thermites with different Al/Mg ratios are investigated by differential scanning calorimetry (DSC) , ignition and combustion measurements respectively. The results show that the reaction temperatures of AlMg/KMnO4 decrease obviously with the higher Mg contents, the ignition temperatures decrease from 723 K to 493 K, indicating that the thermal reactivity of AlMg/KMnO4 thermites is better than that of Al/KMnO4. The combustion products of AlMg/KMnO4 thermites contain Al2O3, MgO and Mn, thus Mn is produced by the thermite reaction of AlMg/KMnO4. AlMg alloys react with the decomposited product of KMnO4. [ABSTRACT FROM AUTHOR]