采用DSC研究了10.7μm、2.6μm和40 nm铝粉对RDX热分解的影响.结果表明,微米铝粉对RDX的热分解基本没有影响；40 nm铝对RDX的一次分解和二次分解均有明显的促进作用；随着40 nm铝含量的增加,RDX的二次分解峰凸显出来并提前,峰形变得尖锐；当40 nm铝质量分数为30％时,二次分解峰掩盖一次分解峰且RDX的放热量由600 kJ/mol增加到1 600 kJ/mol.采用TG-DTG研究了不同粒度的铝粉(质量分数30％)对RDX非等温热分解反应动力学的影响.结果显示,微米铝粉对RDX的热分解反应动力学几乎没有影响,40 nm铝使得RDX的活化能和指前因子对数值分别由130 kJ/mol和1011.87 s-1变为94 kJ/mol和109.97s-1.RDX和RDX/40 nm铝放热分解的反应机理归属随机成核和随后成长,反应机理分别是n=3/4和n=2/3的Avrami-Erofeev方程.%Effects of aluminum powder with particle sizes of 10. 7μm,2. 6 (μm and 40 ran on the thermal decomposition of RDX were studied by DSC. The results showed that Al powders with particle size of 10. 7 μm and 2. 6 μm had almost no influence on the thermal decomposition of RDX. Al powders with particle size of 40 nm promoted the reaction of the first and the second decomposition peaks. With increase of 40 nm Al content, the second decomposition peak of RDX was sharply embodied and advanced. With 40 nm Al content of 30% (mass fraction) ,the second decomposition peak covered up the first peak completely and the heat of reaction increased from 600 to 1 600 kj/mol. TG-DTG was used to investigate the effects of the aluminum powders(30% mass fraction) with different particle sizeson the thermal decomposition kinetics of RDX. The results indicated that microsized aluminum powder had no effect on the thermal decomposition kinetics of RDX. The Al powder with particle size of 40 nm made the activation energy and pre-exponential factor decrease from 130kJ/mol and 1011.87 s-1 to 94kJ/mol and 109.97 s-1 for RDX, respectively. The most probable mechanism functions of the thermal decomposition of RDX and RDX/40nm Al powder were Avrami-Erofeev equations with n = 3/4 and n= 2/3,respeactively,and the reaction mechanism was classified as nucleus and growth.
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