基于发射光谱法的氩等离子体射流诊断研究

Diagnostic Study of Argon Plasma Jet Based on Emission Spectroscopy

摘要:

利用等离子体进行材料表面处理，其电子温度和电子密度会对材料表面的活性成分产生重要影响。为研究等离子体射流电子温度和电子密度，采用针-环电极结构搭建等离子体放电及光谱诊断试验平台，在大气中实现稳定等离子体射流；利用光谱仪采集氩等离子体的光谱数据，分别采用玻尔兹曼曲线斜率法和斯塔克展宽法计算，并对比分析等离子体射流尖端、射流尖端有无铜箔时等离子体射流的不同轴向位置、铜箔到射流喷口不同距离时射流作用在铜箔表面的电子温度和电子密度变化规律。结果表明：输入电压升高会导致电子温度升高，电子密度降低；等离子体电子温度随轴向距离增加而降低，电子密度随轴向距离先略微升高然后降低。尖端放置铜箔会在一定范围内对电子温度电子密度数值产生影响。当铜箔到射流喷口距离增加时，铜箔表面电子温度先上升后下降，电子密度先下降后上升。且外施电压增加，电子温度达到最大值的位置和电子密度达到最小值的位置到喷口距离越来越远。

Abstract:

The electron temperature and electron density of plasma for material surface treatment will have an important impact on active components of material surface. In order to study the electronic temperature and electron density of plasma jet, the needlering electrode structure is used to build a plasma discharge and spectral diagnosis test platform to achieve stable plasma jet in the atmosphere, and the spectral data of argon plasma are collected by spectrometer, and the Boltzmann curve slope method and Stark broadening method are used resfectively to calculate, compare and analyze the electron temperature and electron density change law at the plasma jet tip, the different axial positions of plasma jet when the jet tip has copper foil or not, of the acting on the surface of copper foil, and and the different distances from copper foil to jet nozzle. The results show that the increase of input voltage will lead to an increase in electron temperature and a decrease in electron density. The plasma electron temperature decreases with the increase of axial distance, and the electron density first increases slightly and then decreases with axial distance. The placement of copper foil at the tip has an effect on the electronic temperature and the electron density value within a certain range. When the distance from copper foil to jet nozzle increases, the electron temperature on the surface of copper foil first rises and then decreases, and the electron density first decreases and then increases. And the applied voltage increases, the distance from the position where the electron temperature reaches the maximum value and the position where the electron density reaches the minimum value is getting farther and farther away.