关键词: 电弧温度, 磁流体动力学, Boltzmann作图法, 微球形钨探针

Abstract: In order to improve the success rate of the preparation of monolithic micro tungsten ball tips, the high-voltage micro-arc was studied during the preparation processes. A multi-physics field coupled simulation model of tungsten-pole high-voltage micro-arc was established to calculate the arc temperature distribution at electrode spacing of 0.5~2.0 mm and voltage of 1~12 kV. The simulation results were then subjected to least-squares fitting, and a mathematical model between the arc temperature and the discharge parameters was obtained. Finally, the mathematical model was validated by building a spectral temperature measurement system based on the Boltzmann graphing method. The results show that the arc is elliptically distributed, and there is a high temperature barrier in the near-anode region, and the anode temperature is much lower than that of the cathode temperature. The arc temperature has a parabolic relationship with the voltage and electrode spacing. The average relative error between the model calculation results and the experimental results is as 3.3%. The model may be used to calculate the arc temperature for controlled preparation of the tungsten ball tips. 

Key words: arc temperature, magnetogas dynamics, Boltzmann graphing method, micro tungsten ball tip