模压TATB基PBX炸药件晶体取向对膨胀特性的影响

炸药件的膨胀特性对其使用性能有重要影响,研究TATB基PBX炸药件晶体取向与膨胀特性的关系,可为控制TATB晶体的形稳性提供基础支撑。采用线膨胀仪测定了颗粒状、片状及原材料TATB晶体所压制药柱沿不同方向的膨胀特性,采用X射线衍射仪和Rietveld全谱拟合精修的方法测定了TATB基PBX炸药件的晶体取向(F),并研究了TATB晶体取向对膨胀特性的影响。结果表明:TATB基PBX药柱存在各向异性膨胀,轴向的膨胀程度约为径向的2倍,膨胀系数(αCTE)与药柱中晶体的取向满足关系αCTE=(7.08+10.37×F)×10-5K-1,药柱的线膨胀系数随晶体取向增大而增大,而不同形貌的TATB晶体所压药柱的取向不同。因此,通过改变晶体形貌可以控制晶体取向,进而抑制药柱膨胀的各向异性,改善TATB炸药的形稳性。

Influence of Crystal Preferred Orientation on Thermal Expansion of Die Pressed TATB Based PBXs

Thermal expansion of explosives have important impact on their applications and investigations on the relationship between thermal expansion and crystal preferred orientation can provide some guide for controlling the shape stability. This paper studied the preferred orientation (F) of 1,3,5-triamino-2,4,6-trinitrobenzene(TATB) crystals using X-ray diffraction and Rietveld refinement, and studied the thermal expansion of die-pressed cylinders with near-spherical, platy and raw materials TATB. Finally, the relationship between the crystals preferred orientation and thermal expansion was investigated. It′s shown that die-pressed TATB cylinders usually take place anisotropic thermal expansion with the coefficient of thermal expansion (CTE) along the diameter about 2 times of that along the radial, and the formula can be pressed as αCTE=(7.08+10.37×F)×10-5K-1. The thermal expansion of TATB cylinders increase with the crystal preferred orientation, and TATB cylinders with different morphological crystals have different preferred orientation. So, we can try to control the preferred orientation by change the crystal morphology, further to restrain the anisotropy of thermal expansion, and finally to improve the shape stability of TATB cylinders.