B/Ti nano-multilayers as effective heat energy source for enhanced micro-initiator

Highlights: • Cu/B/Ti integrated film initiator is fabricated by standard microfabrication technique. • Self-propagation exothermic reaction of B/Ti multilayers could be initiated through electric activation. • A simple method to design and fabricate micro-initiator with tunable performance. • The presence of B/Ti nano-multilayers improves the electric explosion performance. - Abstract: Extensive research of compact and reliable ignition method has extended the applicability of nano-energetic materials to various thermal engineering fields. In this paper, an integrated film initiator was designed and fabricated through combining B/Ti nano-multilayers with a Cu film bridge. Cu film bridge was initially wet-etched and B/Ti multilayers were deposited on the top of Cu film bridge with magnetron sputtering. The periodic layer structure of the B/Ti multilayers was verified by scanning electron microscopy. Self-propagation exothermic reaction of the B/Ti multilayers (2 μm thick) could be initiated by 60 V capacitor discharge, and the reaction temperature can be raised up to 2600 K. Different reaction temperature can be achieved by simply altering the thickness of B/Ti multilayers. The explosion processes of the Cu film bridge and the Cu/B/Ti integrated film bridge were explored by electric explosion tests. Compared to the Cu film bridge, integrated film bridge exhibits improved performances with higher explosion temperature, longer explosion duration time, more violent explosion phenomenon and larger quantities of ejected product particles. These results indicate that the electric explosion performances of micro-initiator could be improved evidently with combination of nano-energetic materials.