【摘要】 阴极表面温度是真空弧等离子体放电过程中一个重要参数,对真空弧等离子体的形成、电极腐蚀预测、热传导以及离子源的寿命都有重要影响。真空弧离子源的阴极具有目标小,放电过程快等特点,其温度的测量,对于时间分辨率和空间分辨率要求都很高,阴极表面温度的测量技术的欠缺,使得仅靠理论解析获得的结果难以得到验证。并且等离子体放电过程中测量仪器极易受到弧光的影响,如何避免放电过程中等离子体的辐射也是采用辐射法测量阴极表面温度要考虑的问题。这无疑给其温度场的测试研究带来困难。针对脉冲真空弧等离子体开展阴极表面温度测试实验有着重要意义,在分析了真空弧等离子体放电特性以及背景辐射特性和等离子体放电阴极测温的实际需求,本文基于高速CCD相机研制了一种新型的多光谱高温计。该高温计采用单色高速CCD相机,主要避免RGB彩色相机不能完全滤除背景辐射的弧光。为使用单色CCD相机实现多光谱辐射测温,设计了高温计的光学系统,该系统采用4孔径分光系统。将4种不同波长的滤光片嵌入到1个滤光片中。该研究设计的高温计可用于2 000～6 000 K的等离子体温度测量。并在中国工程物理研究院电子工程研究所进行现场测试,测试过程中将研制的高温计,通过外部触发形式对等离子体放电过程进行跟踪拍摄,高温计完全拍摄到等离子体放电过程。利用真空弧等离子体金属电极阴极放电的实测数据对高温计进行了验证。实验结果表明,设计的新型多光谱高温计能够用于测量真空弧等离子体放电时阴极温度场信息,测量的温度值低于放电电极的沸点温度,与等离子体放电过程中出现气化现象相符,说明高温计测的是等离子体放电阴极的温度。更多还原

【Abstract】 The cathode surface temperature is an important parameter in the vacuum arc plasma discharge process, which has an important influence on the formation of vacuum arc plasma, electrode corrosion prediction, heat conduction and ion source lifetime. The cathode of the vacuum arc ion source has the characteristics of the small target and fast discharge process, and its temperature measurement requires high time resolution and spatial resolution. The lack of measurement techniques for the surface temperature of the cathode makes it difficult to verify the results obtained by theoretical analysis alone. Moreover, the measuring instrument is highly susceptible to arcing during plasma discharge. How to avoid plasma radiation during discharge is also a problem to be considered when measuring the surface temperature of the cathode by radiation. This undoubtedly brings difficulties to the testing of its temperature field. It is important to carry out the cathode surface temperature test experiment for pulsed vacuum arc plasma. In this paper, the vacuum arc plasma discharge characteristics and background radiation characteristics and the practical requirements of plasma discharge cathode temperature measurement are analyzed. A novel multi-spectral pyrometer is developed based on the high-speed CCD camera. In order to realize multi-spectral radiation temperature measurement using a monochrome CCD camera, an optical system of a pyrometer is designed, and the optical system adopts a 4-aperture spectroscopic system. For the first time, four different wavelength filters are embedded in one filter. The pyrometer designed in this paper can be used for plasma temperature measurement from 2 000 to 6 000 K. The field test was carried out at the Institute of Electronic Engineering of China Institute of Physics and Engineering. The pyrometer to be developed during the test was tracked and shot by the external trigger form. The pyrometer completely captured the plasma discharge process. The pyrometer was verified by the measured data of the vacuum arc plasma metal electrode cathode discharge. The experimental results show that the designed multi-spectral pyrometer can be used to measure the cathode temperature field information during vacuum arc plasma discharge. The measured temperature value is lower than the boiling point temperature of the discharge electrode, which is consistent with the gasification phenomenon during plasma discharge. It is stated that the pyrometer measures the temperature of the plasma discharge cathode.更多还原