| The purpose of this research is to study a novel ignition technology -semiconductor bridge ignition, which may be used to overcome low anti-electromagnetism performance in ignition of missile and rocket. The research development in semiconductor bridge (c) ignition technology has been reviewed in this study. SCB ignition mechanism has been more systematically investigated. One dimensional two-phase model has been established. With this model, micro-courses of convective mass and heat transfer have been simulated for ignition of granular explosives by SCB. Several kinds of SCB chip have been designed and manufactured. The energy consumption of SCB chips has been tested. The ignition circuit has been optimized.Major conclusions from this study are summarized as follows:(1) The numerical simulation calculation results demonstrate that: (a) explosives heating mostly depends on potential heat released by plasma due to SCB at condensation. Surface temperature of explosives could reach 2000K, and it exceed the ignition temperature of explosives. Release duration is also enough to ignite explosives. (b) When the length and width of SCB are kept constant, thickness increase of SCB helps to explosives ignition. (c) When interstice fraction increases, i.e. the loading density decreases, surface temperature of explosives tends to rise. But if the loading density is too decreased, it makes against igniting as the explosives cannot burn by control oneself. (d) The property of explosives has less effect on surface temperature of explosives particle. For explosives with high heat conductivity, surface temperature by calculation is higher.(2) The improved SCB chip with doped silicon may satisfy the conditions of igniting by low voltage. SCB chips by the doped process with oxygen-free silicon diffusion may keep resistance stable and consistent, and impurity concentration gradient helps to decreasing the ignition energy of SCB igniting device.(3) The chips with the structure of doped silicon covered by aluminum electrode are prepared by the working procedure that silicon is doped after eroding the sidestep of chips. Contact resistant and critical ignition energy will be lower. For the chips with multiplayer metal electrode, preparation process is more complex; and the cost is also higher. However its performance is better; the rate of performance to price is higher.(4) In the circuit of fire set for SCB ignition, it will reduce the wasting energy on the switch by using field effect transistor as the trigger, and the Tantalum capacitance seemedmore suitable for the fire set, the impedance of the circuit will be decreased by shortening the wire. A redeeming/compensate circuit was designed and the special integrated circuit was made, the redeeming/compensate circuit can eliminate the effect by concomitant parameters. All of these mean will beneficial to improving the using rate of the energy on SCB ignition.(5) The experimental results show that the initiating device may satisfy the conditions of low-voltage insensitive ignition. The ignition circuit optimized has good ignition performance. Several kinds of pyrotechnics chosen may be ignited by low voltage. The all-round test proves rationality of plan, and the initiating device with good configuration is chosen. Through the analysis of test results, theoretical model of interaction course of initiating device is more thoroughly understood.
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