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The pulsed power switch plays an important role in a wide variety of pulsed power applications, such as plasma science and high-pressure-impact studies. This article develops a shock-induced pulsed power switch based on electroexplosion of exploding bridge wire (EBW). The electrical field distribution and electrothermal coupling of EBW are simulated using COMSOL Multiphysics software to assess the rationality of structural parameters. Employing microelectromechanical system technology, the switches are mass-produced with only three steps, improving experimental efficiency and lowering the cost. Electrical tests are conducted at a series of operation voltages varying from 600 to 1800 V, and the results indicated that peak current increases linearly with operation voltage, while delay time and rise time all show a slowly declined trend. A potential conduction mechanism is discussed for better understanding, and switch resistance is described mathematically. Finally, microchip exploding foil initiators are used as a test vehicle to verify the capability of the switch, and ultrafine hexanitrostilbene (HNS-IV) pellets are successfully detonated at 0.15 μF/1300 V after the switch is closed. [ABSTRACT FROM AUTHOR]

A planar trigger switch constituting of three electrodes was designed and fabricated using low-temperature cofired ceramic, and characterized under an atmospheric pressure. The results showed that when the operating voltage ranges between 77.2% and 86.8% of its self-breakdown voltage, the inductance of the switch was lower than that of commercial spark gap switch by approximately 60 nH, the current rising time was shortened by nearly 1/2, and the peak current increased by about 30%. The peak current and rising edge were 4000 A and 146 ns at 0.22 μF/2.0 kV, respectively, which was in agreement with simulation values well. Subsequently, the switch was devised to be in situ integrated with an exploding foil initiator together. The electrical characterizations were performed on the chip, obtaining the switch's rapid turn-on time of 29 ns and a large current density of $1.08 \times 10^{8}\,\text{A}\cdot \text{cm}^{-2}$ at 0.22 μF/2.25 kV. Furthermore, photon Doppler velocimetry was exploited to capture the detailed trajectory of a 50-μm-thick flyer with an extracted terminal velocity of 2200 m/s. Finally, boron–potassium nitrate pellets and hexanitrostilbene pellets were used to successfully verify the practicability of the chip in the ignition and detonation of explosives. [ABSTRACT FROM AUTHOR]

In this paper, a possible conduction model of a kind of plasma switch induced by electroexplosion of the p-n junction was established to better understand the underlying mechanism. The model showed that the resistance of the plasma switch is considerable before switching and a constant during closing, which was validated by complementary experiments. Additionally, several parameters were defined to evaluate the performance of this type of plasma switch. Finally, a highly integrated microchip exploding foil initiator (McEFI) was designed and fabricated using the microelectromechanical system (MEMS) technology. Electrical characterizations, ignition test, and initiation test were conducted to demonstrate the capability of the McEFI, as well as the plasma switch, and the results indicated that the minimum firing voltage is 1150 V/ $0.15~\mu \text{F}$ , providing new ideas for the development of not only McEFI but also low-energy EFI (LEEFI). [ABSTRACT FROM AUTHOR]

A planar ignitor-based on low temperature co-fired ceramic (LTCC) and pyrotechnical micro electro mechanical system (PyroMEMS) technologies was designed and prepared in this paper. The planar ignitor is mainly composed of output charge layer, silicon safe and arm (Si-S&A) layer, and LTCC circuit base. Si/Pb3O4, C6H2(NO2)3OK/KClO4, and B/KNO3were selected as ignition charge, gas charge, and transfer charge, respectively. The ignition circuit and main structure of the planar igniter were made by the LTCC process. Si-S&A was etched from monocrystalline silicon, which does not need environmental force to disarm. Preparation process of main components of planar ignitor that is suitable for mass production was introduced in detail. Simulation of PyroMEMS S&A actuation based on pendulum method was performed to save time for proof test. Finally, experimental verification on PyroMEMS S&A actuation and combustion propagation of B/KNO3transfer charge were completed successfully. Results show that the idea of a planar ignitor inserted with PyroMEMS S&A device is feasible. [2018-0075] [ABSTRACT FROM AUTHOR]

In this letter, a highly integrated conjoined device, single shot switch and an exploding foil initiator (S3-EFI) chip, was fabricated with microelectromechanical system scale fabrication methods. Photon Doppler velocimetry was utilized to characterize the behavior of the flyer at firing voltages ranging from 1.00 to 2.40 kV. Electrical characterizations were then performed on the chip to obtain some fundamental parameters, such as current and voltage, and a peak current of 1.73 kA was observed at 1.50 kV. Moreover, ultrafine hexanitrostilbene pellets were detonated over firing voltage range 1.80–1.40 kV. These results demonstrate the feasibility of the chip and pave the way to the non-lead high-voltage discharge circuit. To the best of our knowledge, this is the first time to integrate exploding foil initiator with a high-voltage switch. [ABSTRACT FROM AUTHOR]

In an effort to investigate the characteristics of electro-exploding products generated by Al/CuO-semiconductor bridge igniters, high-speed camera and spectrum diagnosis systems are employed in this paper. By using the high-speed camera system, the electro-exploding processes are recorded and the results indicate that electro-exploding processes include extrinsic conduction, intrinsic excitation, melting, vaporization, plasma discharging, and Al/CuO combustion. During this process, the spatial dimensions of plasma could reach to 8.7 mm in vertical direction under excitation energy of 47~\mu \text F/50~\text V . Meanwhile, the Al/CuO films are ejected from ceramic housing by plasma shock wave, combust upon plasma and plume. According to the results from the spectrum diagnosis system, it is noted that the temperature maintains 4000–6500 K for 65~\mu \texts . [ABSTRACT FROM AUTHOR]