引燃电极的制备及工艺研究

【作者】 柏艳英；

【导师】 王亚非；

【作者基本信息】 电子科技大学 ， 物理电子学， 2005， 硕士

【摘要】 引燃管作为高压开关在高功率脉冲装置中得到了广泛的应用。引燃极是引燃管的关键部分之一,它的好坏直接影响着引燃管的可靠通断、抗熔焊、截流、耐压、温升、寿命等等。但是实验和实际应用中的引燃电极性能不稳定,机械强度不高,不便运输和储存,也不能进行批量生产,其范围是根据经验和各个制造厂的无数次试验确定。本论文从引燃管的工作原理和引燃电极的性能要求出发,通过粉末冶金方法,研制出了无毒、引燃率高、机械强度好、性能稳定且能进行批量生产的引燃电极。为制得性能优良的引燃电极,本文开展了以下工作: 1.首先根据引燃管的工作原理、弧光放电特点和引燃电极的热分布,得到引燃电极的性能要求,即:引燃极不被水银浸润;良好的导热性,长期通电时温升不高;良好的导电性,但在高温下保持一定的电阻率;并具有一定的抗氧化性,好的抗熔焊性和耐电磨损性。2.再根据引燃电极的性能要求,进行原料和外形设计。通过比较常用于高温下的电绝缘材料的热电性能,选择碳化硼、氮化硼、氧化镁、氧化铝等材料,并按各材料的物理化学性质掺入半导体材料硅,进行严格配方。由引燃电极与水银的不浸润性,设计引燃电极的下端为圆锥形。3.选择了两个配方进行实验。由粉末冶金方法,将所选原料按配方比例混合,经模具压制成型;再由粘接剂的碳化和挥发性质设计烧结制度并在真空炉烧结成样品;测试引燃电极样品的机械强度、引燃率等性能,并进行XRD物相和扫描电镜分析,找出影响引燃电极的性能的因素。经多次配粉、压制、调节烧结制度进行烧结,得到配方1 在950℃下烧结的电极样品性能最好:机械强度高,引燃性能好且稳定。同时可知成分、表面致密度和保护粉影响引燃电极的性能。更多还原

【Abstract】 Ignitron ,a high voltage switch,is abroadly used in high power impulse equipment. Ignitor is one key part of ignitron, and it’s performance influence directly the credible on-off, contradictable fuse, breaking current, resisting voltage, rising temperature and life-span etc. of ignitron. But the ignitors used in produce and experiment are instabile, low strong , discommodious transported and deposited. they cant’t be produced in batch and their use are confirmed by experience or much experiment. This dissertation discusses ignitor’s produce through power metallurgy following ignitron work principle and ignitor performance requirement. We get ignitors with strong body, high ignition, no poison ,stabile performance and produced in batch. In order to produce high performance ignitor, we do much work as follow: 1. At first, through ignitron work principle, arc discharge characteristic and heat distribution, ignitor’s performance requirement is got, namely: ignitor can’t be soaked by mercury;ignitor has good heat capability and it’s temperature is not too high under electrified for long time;ignitor has good electricity and keep some electric quotiety at high temperature; ignitor can resist oxidation ,smelt and causticity. 2. Secondly, we design ignitor’s material and shape obeyed ignitor’s performance requirement. BC, BN, MgO, Al2O3 etc. are choosed after the thermoelectricity of insulated material at high temperature is compared. We confect strictly material and add some Si according material physical chemistry. Because ignitor is not soaked by mercury, it’s shape is designed in taper. 3. We do experiment with two confection (named No.1 and No.2). In term of metallurgy, all of material are mixed at ratio and pressed in mould. Ignitor specimen is sintered in vacuum furnace in view to sinter curve which is made according to glue carbonization and evaporation. In order to find causation witch affect ignitor performance, we test ignitor’s some performance such as intensity, ignition and resistance, and XRD and SEM更多还原