钨极高压微电弧温度模型的建立与验证

Temperature Modeling and Verification of High-voltage Micro-arc with a Tungsten Electrode

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。

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.