Preparation And Representation Of Nano-composite Energetic Materials RDX/Fe₂O₃-Al₂O₃

Acquiring high energy density is one target of energetic materials research.Not only high energy density and High power can be combined, but high energyrelease rate and efficiency performance advantages can be comprehensive. In thispaper, binary oxide aerogel Fe₂O₃-Al₂O₃are prepared via sol-gel and supercriticalfluid technologies. At the same time, nanoscale composite of RDX and aerogel isachieved. The morphology, particle size and composition of the aerogel ischaracterized by scanning electron microscope （SEM） and fourier infraredspectrometer（FTIR）. Finally, the mechanical sensitivity of nano-compositeenergetic materials Fe₂O₃-Al₂O₃is tested.The process conditions of preparing binary oxide aerogel by sol-gel methodwere explored through a large number of experiments in this paper. The metal saltsmole ratio of FeCl₃·6H₂O and AlCl3·6H₂O was2:1.The volume ratio of2:1N, N-dimethyl formamide and ethyl acetate mixed solvent was needed to add2500-3000mL by per mole metal solutions.The mole ratio of propylene oxide andmetal salt ions was1:300-1:430, and the aging time was24h.In above conditions,the nature of prepared wet gel was stable, and the skeletal structure was good. Onabove basis, energetic material RDX was dissolved in the mixed solvent to make itinto the gel three-dimensional structure in molecular state. At last, the compositeenergetic material which the RDX mass fraction was90%was prepared bysupercritical drying. The conditions of supercritical drying process were15MPa ofpressure,45℃of temperature,16L/h of inlet velocity,30min of holding pressuretime,2L/h of air change rate and3bar/min of pressure relief rate.The test result of morphology and structure via SEM shows that:nano-composite particles are spherical, the particle diameter is about50nm, and thedistribution is narrow and uniform. The growth of RDX is controlled fully andeffectively by the pore structure. The analysis result of compound ingredients shows that: the characteristic peaks of Fe₂O₃, Al₂O₃and RDX all exist in thecompounds. In addition, two performance tests have been done to thenano-composites. The analysis of the impact sensitivity test results show that:characteristic height of prepared compounds respectively enhances42.3cm and27.1cm compared with crude RDX and mechanical hybrid composites containing90%RDX.With the reduction of quality percentage of RDX, the impact sensitivityis reduced; Friction sensitivity test result shows that: with the increase of qualitypercentage of RDX in compounds, the friction sensitivity is enhanced. Test resultsof the mechanical sensitivity show that sensitivity of nano-composite energeticmaterial is reduced compared with RDX. It shows that the prepared compoundsbecome insensitive and the security is improved.