将激光诱导击穿光谱(LIBS)技术直接应用于钢液成分的检测。 研究结果表明, 氩气作为保护气不仅可以避免钢液表面的氧化, 同时可以增强等离子体信号强度。 在氩气氛围下, 钢液表面被聚焦成高功率密度的脉冲激光击穿形成等离子体, 利用耦合CCD的多通道光纤光谱仪探测等离子体在冷却过程中发射的光谱信号, 得到钢液组分的相关信息。 根据分析谱线选取原则, 确定了主要合金元素Mn, Si和Cr的特征谱线, 并建立了相应元素的定标曲线, 曲线的线性拟合度均在0.925以上, 对应的质量浓度检测限分别为75.7, 23.8和724.5 μg·g-1。

The technique of laser induced breakdown spectroscopy (LIBS) was applied to analyze the composition of liquid steel. The results of research indicated that oxidation of liquid steel on the surface could be avoided because the argon and the plasma signal was enhanced at the same time. The surface of liquid steel was excited by high-energy pulse laser and plasma was formed in argon atmosphere. The spectral signal was collected with a multi-channel CCD spectrometer when the plasma cooled off and relevant information about the composition of samples was obtained. The characteristic spectral lines of analyzed elements were selected according to the selecting principle of line in LIBS and the calibration curves of major alloying elements Mn, Si and Cr were constructed. The degrees of linear fitting were all more than 0.925 and the limit of detection of Mn, Si and Cr were 75.7, 23.8 and 724.5 μg·g-1, respectively.