铝粉粒度对RDX热分解动力学的影响

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...

Effect of Aluminum Particle Size on the Thermal Decomposition of RDX

Effects of aluminum powder with particle sizes of 10.7 μm,2.6 μm and 40 nm 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 sizes on 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 130 kJ/mol and 1011.87 s-1 to 94 kJ/mol and 109.97s-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.