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

摘要： 为提高一体式微球形钨探针的制备成功率，对制备过程中高压微电弧进行了研究。建立了钨极高压微电弧的多物理场耦合仿真模型以计算电极间距在0.5~2.0 mm、电压在1~12 kV时的电弧温度分布；然后对仿真结果进行最小二乘拟合，进而得到了电弧温度与放电参数之间的数学模型；最后，基于Boltzmann作图法搭建了光谱测温系统，并对数学模型进行了验证。研究结果表明：电弧呈椭球形分布，近阳极区存在高温屏障，阳极温度远低于阴极温度；电弧温度与电压、电极间距之间均为类抛物线性关系；模型计算结果与实验结果的平均相对误差为3.3%。该模型可用于计算电弧温度，从而实现钨探针的可控制备。

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