激光诱导Ni等离子体特性的研究  

Investigation on the Properties of Laser Induced Ni Plasma

作　　者：张贵银[1] 宋欢 刘洋 任芝 郑海明[2] ZHANG Gui-yin;SONG Huan;LIU Yang;REN Zhi;ZHENG Hai-ming(School of Mathematics and Physics,North China Electric Power University,Baoding 071003,China;Department of Mechanical Engineering，North China Electric Power University，Baoding 071003，China)

机构地区：[1]华北电力大学数理系,河北保定071003 [2]华北电力大学机械工程系,河北保定071000

出　　处：《光谱学与光谱分析》2018年第8期2578-2582,共5页Spectroscopy and Spectral Analysis

基　　金：国家自然科学基金项目(11174078);中央高校基本科研业务费支持项目(2016YQ11;2016MS134;2017MS198)资助

摘　　要：以Nd·YAG激光器的二倍频输出作为激发源,获得了激光诱导Ni等离子体的发射光谱,基于发射光谱,对等离子体电子激发温度和电子密度进行了测量,其典型值分别为3 714K,4.67×10^(16)cm^(-3)。测量了等离子体电子激发温度和电子密度的空间分布,发现沿垂直于激光传播方向的径向,随到中心点距离的增加,等离子体辐射的强度减小,但线型和线宽不变,表明等离子体电子激发温度和电子密度沿径向均匀分布。沿激光传播方向,随到样品表面距离的增加,等离子体辐射强度、电子激发温度和电子密度先增加后降低,在距样品表面1.5mm处,达到最大值。采用激光诱导击穿光谱技术进行相关探测时,收集距离样品表面1.5mm处的发射谱,有利于提高探测灵敏度。With the harmonic output 532 nm of a pulsed Nd·YAG laser as radiation source, the emission spectrum of laser induced nickel sample plasma was investigated. Most emission peaks of the spectrum were assigned to NiⅠand NiⅡ. The electronic excitation temperature and electron density in the plasma was measured. They were 3 714 K and 4.67×1016 cm-3 respectively. The spatial distribution of the temperature and electron density were measured by moving the detection head of a fiber along the direction parallel and vertical to the laser beam. It showed that the emission intensity of the plasma in the centre was most strong. With the measurement points moving apart from the center along the direction vertical to the laser beam, the emission intensity decreases, but both of the line profile and width of the emission spectral was almost invariable. So the electronic excitation temperature and electron density in the plasma was uniform along this direction. While along the direction parallel to the laser beam, the temperature and electron density were not uniform. They took the maximum value at the position about 1.5mm apart from the sample. We ought to collect the emission spectrum of this position when perform relative investigation with the technique of LIBS. This can ensure higher detection sensitivity.

关 键 词：激光诱导击穿光谱 镍板 电子激发温度 电子密度 空间分布 

分 类 号：O433.4[机械工程—光学工程]