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• The LTCC technology and MEMS was used to prepare a modular integrated EFI system. • The modular integrated EFI system has higher integration and smaller volume. • The research has realized the low voltage input and control of EFI system. • Characterization indicated that the system has higher energy utilization. In this study, the flyback high-voltage conversion unit, capacitor discharge unit, and EFI chip of the exploding foil initiator (EFI) system were highly integrated using low temperature cofired ceramic technology and MEMS, forming a modular integrated system with boost, discharge, and firing functions. The modular integrated EFI system used the design idea of system in a package, selected chip-level or planar components, eliminating the need for connecting wires and reducing the volume of the EFI system to 5.67 cm3. Compared with the traditional EFI system, while analysis from the characterization showed that the integrated structure reduced the loop inductance of the system to 27 nH, which was 55 % lesser, it accelerated the flyer to 3800 m/s, which was 15.2 % faster. These accomplishments indicated that the energy utilization rate of the integrated system was higher. The input voltage of the system was reduced from traditionally high voltage of 1250 V to lower voltage of 24 V due to the integrated-system boost function. Simultaneously, the 5 V MOS controlled thyristor (MCT) chip was selected to replace 1800 V∼2500 V spark gap switch as the working voltage, thus making 5 V the switching voltage of the system. These changes made high safety operation of the system. Moreover, the system had used modular design and manufacturing to improve its reliability and obtained the characteristics of mass production. [ABSTRACT FROM AUTHOR]

[Display omitted] • An energetic Al/Ni reactive multilayer foil is prepared by magnetron sputtering and wet etch method. • Intermetallic reaction of Al/Ni is beneficial for improving energy efficiency and plasma density. • Energy efficiency of the Al/Ni exploding foil is measured to be 30.9% higher than that of Cu exploding foil. • A direct ignition method is proposed by utilizing the abundant plasma generated at Al/Ni exploding foil, instead of driving a slapper. In order to lower the firing voltage, an energetic Al/Ni exploding foil (Al/Ni-EF) with enhanced energy efficiency and plasma density was prepared in this study, to realize the direct ignition of pyrotechnics. An Al/Ni reactive multilayer foil (Al/Ni-RMF) was firstly synthesized by magnetron sputtering and wet etch method, and its structure and exothermic behavior were investigated. Scanning Electron Microscopy, Atomic Force Microscope and X-ray Diffraction characterizations confirmed the periodic layer structure of Al/Ni-RMF with a total thickness of 4 μm. The highest heat release in Al/Ni-RMF could be achieved theoretically when the ratio of Al and Ni was 1.5, and thus the thickness of single Al and Ni layer was determined to be 300 nm and 200 nm, respectively. The obtained Al/Ni-RMF was subsequently fabricated to be an exploding foil, and its electric explosion performance was further studied. Energy efficiency of the Al/Ni-EF was measured to be 85.9% during the electric explosion process, which was 30.9% higher than that of Cu exploding foil (Cu-EF). The plasma generated at Al/Ni-EF had larger volume, longer duration time and higher temperature than Cu-EF due to the intermetallic reaction between Al and Ni, which was beneficial for the direct ignition of Boron/Potassium Nitrate composition (B/KNO 3 , BPN). Afterwards, a special Al/Ni-EF ignitor without slapper was constructed, and the fierce ignition of BPN at the minimum discharge voltage of 800 V was observed. Above results confirmed the feasibility of direct ignition, such a unique strategy was beneficial for the development of low-energy, low-cost and miniaturized ignitor. [ABSTRACT FROM AUTHOR]