磁约束激光诱导煤粉等离子体特性的研究  

Study on characteristics of laser⁃induced powdered coal plasma under magnetic confinement

作　　者：李慧敏 龚瑞昆 周国庆 LI Huimin;GONG Ruikun;ZHOU Guoqing(College of Electrical Engineering,North China University of Science and Technology,Tangshan 063210,China;Department of Automation Engineering,Tangshan Polytechnic College,Tangshan 063210,China)

机构地区：[1]华北理工大学电气工程学院,河北唐山063210 [2]唐山工业职业技术学院自动化工程系,河北唐山063210

出　　处：《现代电子技术》2021年第19期150-152,共3页Modern Electronics Technique

基　　金：国家自然科学基金资助项目(61203343)。

摘　　要：为了研究磁场约束下激光诱导煤粉等离子体特性,以及在不同的磁场强度作用下,对煤粉等离子体的光谱强度、电子密度、电子温度进行研究。实验采用外加磁约束的方式搭建激光诱导击穿光谱实验平台,使用两块磁性相反的方形永磁铁形成一个中心等离子体区域可近似认定为稳磁场,通过调节板间距离改变磁约束强度进行研究。实验结果显示:在其他实验条件相同的情况下,随着磁场强度的逐渐增强,等离子体的光谱强度、电子密度、电子温度均有所增强。当磁场强度为0.67 T时,与无磁场约束时相比,Mg、Fe、Al元素等离子体的光谱强度分别增长了33.8%,68.6%,67.1%,Ca元素电子温度增长了24.1%,Al元素电子密度增长了11.5%。因此,可得出外加磁约束的方式是提高激光光谱质量的优化条件之一。In order to study the characteristics of laser⁃induced powdered coal plasma under magnetic confinement and its spectral intensity,electron density and electron temperature under different magnetic field intensities,an experimental platform for laser⁃induced breakdown spectroscopy(LIBS)is set up by additional magnetic confinement.Two pieces of permanent magnets with opposite magnetic properties are used to form a stable magnetic field which can be approximately determined by the central plasma region.The magnetic confinement intensity is changed by adjusting the distance between two magnets.The experimental results show that,under the same experimental conditions,the spectral intensity,electron density and electron temperature of the plasma are enhanced as the magnetic field intensity increases gradually.When the magnetic field intensity is 0.67 T,the spectral intensity of magnesium,iron and aluminum plasma increases by 33.8%,68.6%and 67.1%respectively,the electron temperature of calcium increases by 24.1%,and the electron density of aluminum increases by 11.5%,in comparison with that without magnetic field confinement.Therefore,the way of adding the magnetic confinement is one of the optimization conditions to improve the laser spectral quality.

关 键 词：煤粉等离子体 磁约束激光诱导 激光诱导击穿光谱 光谱强度 磁约束强度 电子密度 电子温度 

分 类 号：TN2-34[电子电信—物理电子学] O433[机械工程—光学工程]