| With decent shock resistance, RFI resistance, antistatic ability and anti-electromagnetic ability, exploding foil initiation system has become a novel kind of detonator. The system is not only very effective and efficient to use in weapons but quite safe and reliable, so it has been widely used in many fields, such as initiation system of nuclear weapon, antitank guided missile, air-to-air missile and torpedo. As the impulse power device in exploding foil initiation system needs to store electric energy in capacitance and then release it in a short time, the high-voltage switch is the key to transfer electric energy to exploding foil,which could determine the whole efficiency of system. So it is very important to choose the right switch.This thesis studied the research of high-voltage switches in China and around the world by comparing their advantages and disadvantages, and then we devised a new kind of solid switch using epoxy resin. Preparation technology was studied in this thesis as well as the effect of trigger electrode’s width and film thickness using simulation software Maxwell 2D and 3D. Then we used epoxy resin as sealing material and studied the feasibility of the new device using the software to find the proper size and structure. Epoxy resin’s curing technology was studied under room and high temperature. After that, heat stability of the material was studied as well as its effect to switch’s property. Finally, the properties of high-voltage switch was studied including self-breakdown voltage, resistance and delay time, with comparing the morphologies of solid switch and air switch after working.Firstly, this thesis studied the principle and operation process of magnetron sputtering machine Discovery 635, with technology of coating film studied. The concentration of Cu2+was measured in etchant under certain time and the concentration stayed stable after 180 s,which means the etching process is completed. By comparing the switch’s morphology using different concentration developing liquid, we get the conclusion that the best concentration of KOH is 5‰ because switch’s morphology is quite decent under such condition. The thickness of cooper film can be controlled by adjusting time with sputtering power reaching 600 W and argon flow rate reaching 30 sccm. Generally speaking, 4 μmSwitch needs 3300 s under such conditions and the real case should be considered based on the target’s condition.Secondly, the size and structure of switch was studied by using Maxwell software. The effect of film thickness was studied using Maxwell 3D and we got the conclusion that electric field strength is increasing from 3 μm to 4 μm and then decreasing between 4 μm to5 μm, with the maximum field strength appearing at the same position. The effect of trigger electrode width was studied using Maxwell 2D and we got the conclusion that the field strength is increasing when width increases. Using epoxy resin as sealing material is studied using the software: when the distance between trigger electrode and negative electrode is 0.05 mm and trigger voltage is 2500 V, the maximum number of electric strength is around 5.2×107V?m-1; adjusting the distance and trigger voltage to 0.08 mm and2000 V, and then the figure for electric strength is about 3.0×107 V?m-1. To sum up, the switch whose distance between trigger electrode and negative electrode is between 0.05 mm and 0.08 mm can be used with trigger voltage being from 2000 V to 2500 V.Finally, epoxy resin’s curing technology was studied under room temperature and high temperature. After testing the the heat stability using TG analysis, we got the conclusion that epoxy resin can stand 200 ℃ without decomposing. The effect of trigger electrode width was studied using oscilloscope and high voltage power supply, and we got the conclusion that the field strength is increasing when width increases leading to the self-breakdown voltage’s decrease, which is consistent with simulation’s result. Then the effect of film thickness was studied and we got the conclusion that the self-breakdown voltage is decreasing when film thickness increases from 3 μm to 5 μm because of point discharge. Comparing the self-breakdown voltage of air switch and solid switch tells us epoxy resin can increase the voltage of switch by 400~600 V. The resistance and inductance of switch was given, which is 102.3 Ω and 91.1 nH respectively. For the switch whose trigger gap is 0.08 mm, electrode gap is 0.8 mm and film thickness is 4 μm, the delay time is about 20 ns using 2200 V working voltage and 2000 V trigger voltage, which almost has same property with gas switch. Air switch and solid switch’s morphologies were compared after triggering and it is obvious that solid switch’s morphology damage was more serious because of the higher working voltage. |
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