Performances and direct writing of CL-20 based ultraviolet curing explosive ink
Sheng Kong, Dongjie Liao, Yu-meng Jia, Chongwei An, Chunyan Li, BaoYun Ye, Bidong Wu, Jingyu Wang, Hao Guo, Zhiwei Hong
Abstract
A new type of explosive ink formulation that can be quickly cured was prepared with unsaturated polyester as binder, styrene as active monomer, 2,4,6-trimethylbenzoyl-diphenylphosphine oxide as photoinitiator, and hexanitrohexaazaisowurtzitane (CL-20) as the main explosive. Then the explosive ink direct writing technology was used to charge the micro-sized energetic devices, the curing mechanism of the explosive ink was discussed, and the microstructure, safety performance and explosive transfer performance of the explosive ink molded samples were tested and analyzed. Results indicate that the composite material has a fast curing molding speed, its hardness can reach 2H within 8 min. The crystal form of CL-20 in the molded sample is still ε type. The CL-20 based UV-curing explosive ink formulation has good compatibility, its apparent activation energy is increased by about 3.5 kJ/mol. The composite presents a significant reduction in impact sensitivity and its characteristic drop height can reach 39.8 cm, which is about 3 times higher than the raw material. When the line width of charge is 1.0 mm, the critical thickness of the explosion can reach 0.015 mm, and the explosion velocity is 7129 m/s when the charge density is 1.612 g/cm3.