LIBS对钢液中多元素同时辨识优化方法研究

激光诱导击穿光谱技术具有多元素同时检测的优点,基于钢液成分比较复杂,这一技术越来越多的应用于冶金行业。如果检测到某元素的特征谱线,即可以定性判断激发样品内存在该元素;但因为光谱检测仪器、激发条件与元素探测浓度极限的影响,某元素的谱线在光谱中不存在,并不能说明该元素在激发样品中就不存在,为提高钢液中多元素同时测量的精密度和灵敏度的研究,提出了将数理统计的多元统计分析与激光诱导击穿光谱技术定性分析相结合的优化方法。利用多元中心极限定理,无论总体分布如何,许多多元统计量的分布是近似正态的,选取多元素的若干特征谱线,建立多元素同时辨识的模型与方法,通过实验验证了此方法的可行性。

Simultaneous Multielement Identification Method Used for Liquid Steel by LIBS

The advantage of laser-induced breakdown spectroscopy is simultaneous multi-element identification. Based on liq- uid steel composition is very complex. This technology is widely used in metallurgical industry. If the detected some elements of the spectral lines, which can determine the excitation of the sample in the memory element; but because of the influence of spec- trum detection instrument, excitation conditions and element concentration limit of detection, if spectral line of an element does not exist in the spectrum, which could not explain the element does not exist in the excitation of the sample. To improve the mul- tielement measuring precision and sensitivity for liquid steel, this paper presents a new method. It is combining the multivariate statistical analysis and mathematical statistics, qualitative analysis of laser induced breakdown spectroscopy. Using the multivariate central limit theorem, no matter how many multivariate statistics of population distribution, the distribution is approximately nor- mal, select the background spectral line number of point, model and method to establish the multielement simultaneous identifica- tion. It is through the experiment to verify the feasibility of this method.