采用超临界流体增强溶液扩散技术（ SEDS法）对 RDX进行重结晶细化。探索实验确定 N，N-二甲基甲酰胺为溶剂，浓度为20％。通过正交试验 L9（34）和单因素试验研究分析了影响细化效果的诸多影响因素。结果表明：选择合适的溶剂是避免形成片状或针状晶体的关键。影响结晶效果的因素依次为压力、CO2流速、溶液流速和温度。在流体密度接近液体密度时，CO2流速与溶液流速之比直接影响粒状晶体所占比例及粒度的大小，但浓度最终决定晶体粒度大小。扩试工艺条件是浓度26．7％、温度35℃、压力9．0 MPa、溶液流速2 mL·min-1和CO2流速6 kg·h-1。在此条件下，得到的RDX晶体边缘光滑、形貌规则趋于球形，粒度在为3～5μm、粒度分布均匀、流散性良好，制备量可达32 g·h-1，且机械感度显著降低。%The crystallization refinement of RDX was performed by the process solution enhanced dispersion technique of supercritical fluids(SEDS)method. Exploring experiments were conducted to determine the DMF as solvent and the concentration of RDX/DMF solu-tion as 20%. The factors affecting the refinement efficiency of RDX were investigated and analyzed via orthogonal L9(34)test design and single factor experiment. The results show that suitable solvent is the key to avoid obtaining flake or needle-like crystals. The order of factors affecting the effect of crystallization are pressure,CO2 flow rate,sollution flow rate and temperature. As the fluid density is close to liquid density,the ratio of CO2 flow rate and solution flow rate is directly related with granular proportion and the particle size,but the concentration determines the particle size ultimately. The expanding process conditions are concentration 26. 7%, temperature 35 ℃,pressure 9. 0 MPa,solution flow rate 2 mL·min-1 and CO2 flow rate 6 kg·h-1 . Under these conditions the edge of fine RDX particles obtained is smooth,and shape nearly spherical. The particle size distribution is uniform between 3~5 μm,and the fine RDX particles have good fluidity and low mechanical sensitivity. Its preparation amount can be up to 32 g·h-1.
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