Inkjet Printing of GAP/NC/DNTF Based Microscale Booster with High Strength for PyroMEMS

Abstract

In order to improve the mechanical strength of micro-booster based on 3,4-dinitrofurazanofuroxan (DNTF), 2,4-toluene diisocyanate (TDI) was introduced into the composite binder of nitrocotton (NC) and glycidyl azide polymer (GAP). A full-liquid explosive ink containing DNTF, binder and solvent was printed layer by layer. By the polymer cross-linking technology, the inkjet printed sample with three-dimensional network structure was obtained. The morphology, crystal form, density, mechanical strength, thermal decomposition and micro scale detonation properties of the printed samples were tested and analyzed. The results show that the printed sample has a smooth surface and a dense internal microstructure, and the thickness of the single layer printing is less than 10 μm. Compared with the raw material DNTF, the thermal decomposition temperature and activation energy of the printed samples do not change significantly, indicating better thermal stability. The addition of curing agent TDI increases the mechanical properties and charge density of the energetic composites. The elastic modulus and hardness are increased by more than 20%. The charge density can attain 1.773 g·cm−3, which can reach 95.5% of the theoretical density. The critical detonation size of the sample can reach 1 mm × 0.01 mm or less and the detonation velocity can achieve 8686 m·s−1, which exhibits excellent micro-scale detonation ability.

Observations on Detonation Growth of Lead Azide at Microscale

“…The detonation growth of explosives has always been the focus and hotspot of detonation and shockwave physics [ 1 , 2 ], which possesses great value for understanding the detonation-reaction mechanism and building reaction models for computer simulations [ 3 ]. Although extensive research has been carried out on detonations with large size, few studies which adequately cover the phenomenon at microscale exist, resulting in a lack of novel insights into the miniaturization of pyrotechnics [ 4 , 5 ]. To observe those microdetonations nowadays, various tabletop explosion experiments have been designed with ultrafast diagnostics or advanced techniques [ 6 , 7 , 8 ].…”

A Simple Route of Printing Explosive Crystalized Micro-Patterns by Using Direct Ink Writing

“…The Si-based safe initiator layer contains a micro-actuator, which will be ignited to generate gases that move the screen into the armed position, and a micro-initiator, which will ignite the primary explosive located in its cavity. The charging method for the energetic material in a micro-actuator and a micro-initiator cavity in integrated micro-electro-mechanical system (MEMS) and SAF devices, however, must be precise, automated, and safe [ 12 , 13 , 14 ]. The traditional ways, such as mold pressing and cast molding, are inadequate for fusing in MEMSs due to the slow solidification of the drug column and the lack of accuracy in forming a small-sized explosive column.…”

Energetic Films Realized by Encapsulating Copper Azide in Silicon-Based Carbon Nanotube Arrays with Higher Electrostatic Safety

“…In recent years, micro-electro mechanical systems (MEMS)-related technologies have been widely used to fabricate miniature safe systems and micro-initiators [1][2][3][4]. The currently used lead-based primary explosives can hardly meet the requirements of the micro-initiator for energy due to the miniaturization of the ignition device.…”