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In this study, a novel high-speed flyer launching strategy based on electric explosion and laser coupling was proposed to improve the launching ability of electro-explosively actuators and expand the dynamic high-pressure loading method. First, an electro-explosively actuated flyer launcher with a transparent glass substrate was fabricated by microelectromechanical system (MEMS) scale methods, which acted as a carrier to verify the idea of electric explosion and laser coupling. Then, a device of electric explosion combined with laser driving high-speed flyers was established to study the influence of nanosecond pulsed laser on the flyer launching ability of electro-explosively actuators. Finally, the velocity characteristics of the flyer and the plasma characteristics under coupled conditions are studied. The test results indicated that the introduction of laser had a positive effect on increasing the speed of the flyer. In addition, it was found that the acceleration history of the flyer is affected by the energy of electric explosion, laser energy, and the introduction time of laser.

In this study, metal-interlayer-metal (MIM) structure samples are designed to investigate the breakdown properties of aluminum/cupric oxide (Al/CuO)-based reactive multilayer films (RMFs) and to evaluate the differences in the breakdown properties between the Al/CuO RMFs and the single-layer CuO film sample. The MIM structure samples use Al/CuO RMFs as the interlayers between the top and bottom aluminum electrodes, like a sandwich. The pulsed voltage is produced by a capacitor. The samples are not discharged until the external voltage exceeds the breakdown field strength (EB) of the Al/CuO RMFs. The results show that the EB of the Al/CuO RMFs can be improved by Al interlayers in the RMFs, but the destruction area caused by breakdown is smaller than that of the single-layer CuO film. A theoretical model indicates that the thermal conductivity and vaporization heat are crucial parameters for the breakdown of Al/CuO RMFs. The viewpoint from the breakdown of the Al/CuO RMFs proposed in this study might provide a new way for interpreting the electrical excitation process in RMFs.

In order to probe the self-propagating combustion behavior of aluminum/molybdenum trioxide (Al/MoO3) reactive multilayer films (RMFs), RMFs with varied modulation periods and widths were deposited by the magnetron sputtering method on a glass substrate. Differential scanning calorimetry revealed that thermal reaction was in the solid-solid phase at thin modulation periods (50 nm and 150 nm) and in the liquid-solid phase at the microscale (1500 nm). Furthermore, since X-ray diffraction analysis demonstrated the presence of aluminum oxide, the hot spot and pre-oxidation theory of the interface in Al/MoO3 RMFs allowed logical explanation of the thermal reaction feature. The RMFs achieved stable self-propagating combustion with 50 nm–150 nm modulation periods excited by a laser pulse but not at 300 nm–1500 nm. The average stable combustion velocity was 6 m s−1 at the 150 nm modulation period and reached 10 m s−1 for 50 nm. The two-way analysis of variance demonstrated that the effect of the width on combustion velocity was not significant. Thus, we constructed a one-dimensional (1D) combustion velocity model based on heat transfer theory combing experimental data. The model explored the relationship between the stable combustion velocity and the modulation period.

The integration of composite energetic films (CEFs) with various types of initiators can effectively adjust their performance and represents potential applications in microscale energy-demanding systems. In this study, the Al/Bi2O3/graphene oxide (GO) CEFs were successfully integrated into copper micro-ignitors by electrophoretic deposition, a low-cost and time-saving method. The effects of the Al/Bi2O3/GO CEFs with different GO contents on exothermic performance and ignition properties of micro-ignitors were then systematically investigated in terms of heat release, activation energy, ignition duration, the maximum height of the ignition product, and ignition delay time. The results showed that the addition of GO promoted more heat releases and higher activation energies of Al/Bi2O3/GO CEFs. The addition of ≤3.5 wt. % GO prolonged the ignition duration from 450 μs to 950 μs and increased the maximum height of the ignition product from about 40 mm to 60 mm. However, the micro-ignitors with more than 3.5 wt. % GO cannot be ignited, which suggested that GO played a contradictory role in the ignition properties of micro-ignitors and the controlled GO content was a prerequisite for improved ignition performance. The ignition delay time gradually extended from 10.7 μs to 27.6 μs with increases in the GO contents of Al/Bi2O3 CEFs, revealing that an increase in the weight ratio of GO leads to lower ignition sensitivity of micro-ignitors.

Three types of energetic semiconductor bridges (ESCBs) through integrating different Al/MoOx energetic multilayer nanofilms on a semiconductor bridge have been investigated in this study. The relationships among the critical firing energy, critical firing time, total firing time, and ignition energy as well as the input energy utilization efficiency of these initiators were analyzed. The principal component analysis (PCA) was utilized in the experiments to evaluate the output energy magnitude based on the ignition duration, the maximum flame area, reaction ratio, and other parameters. The results obtained were as follows: (1) The critical firing energy is positively proportional to the modulation periods of nanofilms for the initiators discharged with identical voltage, while the total firing energy and the input energy utilization efficiency do not change significantly; (2) by using PCA, the composite score of the ESCB/50 nm, ESCB/150 nm, ESCB/1500 nm, and SCB is measured at 3.025, 0.250, −1.433, and −1....

The design, fabrication, and characterization of an energetic semiconductor bridge device are presented. The device consists of a semiconductor bridge heating element, which has been selectively coated with Al/MoOx multilayer nanofilms to enhance ignition of a conventional pyrotechnics. Integrated negative temperature coefficient thermistor chip provides protection against electromagnetic and electrostatic discharge events. The device was specifically configured to allow ease of interconnection by wire bonds and silver-filled conductive epoxy. Extensive design validation testing was performed. The device has demonstrated low, predictable firing energy and insensitivity. Al/MoOx multilayer nanofilms have no distinct influence on the electrical properties of semiconductor bridge. Nanothermite reaction provides reliable ignition by being able to ignite across a gap.

An energetic initiator was developed by integrating KNO3@CNTs nanoenergetic materials with a Cu thin-film microbridge realized onto a ceramic substrate. The electro-explosion performances, including the voltage and current properties, the electro-explosion time, and the explosive sensitivity, of the initiator under capacitor discharge were investigated. The process of electrical explosion was observed by highspeed photography. The explosive sensitivity was obtained by Bruceton method. The results show that the Cu thin-film microbridge and the KNO3@CNTs initiator conducted different electro-explosion behaviours. Compared with the Cu thin-film microbridge, the explosive input energy was lower and the output energy was higher. It indicated that the superior electric and thermal conductivities of the carbon nanotubes and the chemical reaction of the KNO3@CNTs nanoenergetic materials were beneficial for the miniaturization of electropyrotechnics.

This paper describes the ignition characteristics of Al/CuO nanoenergetic multilayer films (nEMFs) integrated with semiconductor bridge (SCB). The as-deposited Al/CuO nEMFs were identified with SEM and differential scanning calorimetry. Results show that distinct Al/CuO nEMFs are sputter deposited in a layered geometry, and the Al/CuO nEMFs gives a reaction heat equal to 2181 J/g. The firing experiments show that Al/CuO nEMFs have no influence on the electrical properties of SCB. Furthermore, the rapid combustion of Al/CuO nEMFs is able to assist SCB generating high-temperature plasma and products, such that enhance the ignition reliability.

An investigation on the influence of Al/CuO reactive multilayer films (RMFs) additives on exploding foil initiator was performed in this paper. Cu film and Cu/Al/CuO RMFs were produced by using standard microsystem technology and RF magnetron sputtering technology, respectively. Scanning electron microscopy characterization revealed the distinct layer structure of the as-deposited Al/CuO RMFs. Differential scanning calorimetry was employed to ascertain the amount of heat released in the thermite reaction between Al films and CuO films, which was found to be 2024 J/g. Electrical explosion tests showed that 600 V was the most matching voltage for our set of apparatus. The explosion process of two types of films was observed by high speed camera and revealed that compared with Cu film, an extra distinct combustion phenomenon was detected with large numbers of product particles fiercely ejected to a distance of about six millimeters for Cu/Al/CuO RMFs. By using the atomic emission spectroscopy double line tec...

This paper deals with the energetic igniters realized by integrating Al/CuO reactive multilayer films (RMFs) with Cr Films, which could be used in micro-ignition system. The as-deposited Al/CuO RMFs has been characterized with varied analytical techniques. Results show that distinct Al/CuO RMFs is sputter deposited in a layered geometry, and the Al/CuO RMFs gives a heat of reaction equal to 2760 J/g. The structure of igniter is similar to a capacitor, which may place an electric field across the igniter and allow the instantaneous large-current to drift through the igniter. Firing characteristics of the igniter were accomplished using constant voltage firing set. The experiment shows that the ignition delay time and total released energy of the igniter discharged in 40 V are 0.7 ms and 482.34 mJ, respectively. In addition, the explosion temperature could keep an approximately constant value of 3500 °C for 1.4 ms.

A dielectric structure pyrotechnic initiator was proposed and the initiator samples were designed and realized by integrating Ti/CuO-based reactive multilayer films on ceramic substrate. The dielectric structure consists of essentially two titanium films separated by a copper oxide (CuO) film, which is just like as a capacitor guaranteeing the initiator will not be discharged until the external voltage has exceeded the breakdown strength of the CuO film. Results of the electrical explosion experiment show that the breakdown strength of 1-μm-thick CuO film is 60 V, and the initiator has “late time discharge” characteristics, which will improve the conversion ratio of the electricity greatly, and there is a nanoscale exothermic reaction in the electrical explosion process. A systematic temperature measurement model based on the “double-line atomic emission spectroscopy of copper element” was presented and used to test the explosion temperature and duration. The ejected explosion flame was seen clearly with ...