钢模压制下高品质HMX晶体的损伤规律

Crack and Damage in Insensitive HMX Crystal during Pressing

为了揭示粒度分布与压制期内含能晶体损伤程度的关系,研究了3种不同粒径的高品质HMX炸药在压制后微结构和粒度分布的变化。结果表明,随着HMX晶体粒径的增大,晶体表面逐渐形成裂纹,其尖端和棱角发生破碎。当晶体尺寸达到222.5μm时会出现明显的穿晶断裂。采用两种粒度的HMX级配,可减少对晶体中的损伤。压缩刚度法所得HMX的黏结强度和光电子能谱所得PBX造型粉的包复度表明,随着颗粒粒径的增大,炸药的包覆效果和力学强度降低,导致压制PBX中更多晶体的破碎。

In order to explore the relation between the particle size distribution and the damage degree of energetic crystal during pressing, three kinds of insensitive HMX crystals with different particle size were chosen to analyze their change of mierostructure and particle size distribution after being pressed. The results show that as the particle size increases, more cracking and damages appear at the surface and cusp of crystal respectively. The transcrystalline rupture increases when average particle size is about 222.5μm. The damage decreases when coarse particle and fine particle mixed together. The coherence strength of HMX by compressive stiffness method and the coating degree of PBX molding power by XPS show that as the particle size of HMX increases,the mechanical strength and coating de- gree decreases, which result in more cracking in pressed PBX.