准光学薄态下自吸收校正的铜锌合金CF-LIBS定量分析研究  

Quantitative analysis of Cu‐Zn alloys using CF‐LIBS with self‐absorption correction in a quasi‐optically thin state

作　　者：张轩搏 李守杰 李颖[1] 田野[1] 叶旺全 郭金家[1] 郑荣儿[1] 卢渊[1] ZHANG Xuanbo;LI Shoujie;LI Ying;TIAN Ye;YE Wangquan;GUO Jinjia;ZHENG Ronger;LU Yuan(College of Physics and Optoelectronic Engineering,Ocean University of China,Qingdao 266100,China)

机构地区：[1]中国海洋大学物理与光电工程学院,山东青岛266100

出　　处：《量子电子学报》2024年第3期485-495,共11页Chinese Journal of Quantum Electronics

基　　金：国家自然科学基金(62205320)。

摘　　要：免定标(CF)方法是一种面向激光诱导击穿光谱(LIBS)的定量分析方法,可在无定标曲线的情况下直接完成探测元素的含量计算,但传统CF-LIBS的实际定量结果往往与真实值存在一定差距。为了提高CF-LIBS定量分析结果的精度,本文使用三种不同质量比的标准铜锌合金靶进行CF-LIBS定量分析计算,通过“准光学薄态逼近”和“谱线自吸收校正”,成功实现了合金靶中Zn/Cu质量比的准确定量。在具体实施过程中,首先通过调节“激光能量”和“探测延时”逼近元素双线比的理论强度值,以此寻获等离子体的“准光学薄”状态。在此基础上,根据元素谱线计算相应的自吸收系数,依据该系数进行LIBS光谱强度的修正,以此完成LIBS谱线的自吸收校正。两部分工作的有效结合,显著提升了CF-LIBS定量的分析精度,结果显示测算的铜锌元素质量比与实际含量非常吻合,三种标准铜锌合金靶的定量误差均小于3.5%,证明了本文所提出方法的有效性和合理性,未来有望在其他领域获得应用验证。The calibration-free(CF)method is a quantification approach for laser-induced breakdown spectroscopy(LIBS)that enables the content determination of detected elements without a calibration curve.However,the actual quantitative results of traditional CF-LIBS often exhibit discrepancies with respect to the real values.In order to improve the accuracy of CF-LIBS quantitative analysis results,three standard Cu-Zn alloy targets with different mass ratios were used for the calculation of CF-LIBS quantitative analysis,and accurate quantification of the Zn/Cu quality ratio in the alloys was successfully achieved through utilization of"quasi-optically thin state"and"self-absorption correction".In the implementation,we firstly approached the theoretical intensity ratio of copper lines(I521.8 nm/I515.3 nm)by adjusting laser energies and detection delays,so as to find the"quasi-optically thin state"of the plasma.And then,under such a plasma state,the spectral intensity was well corrected by the selfabsorption via referencing the corresponding coefficient.Based on the proposed method,the Cu/Zn quality ratio was accurately determined using CF-LIBS,exhibiting excellent agreement with the actual content.The quantitative biases of the three standard copper-zinc alloy targets were observed all less than 3.5%,indicating high precision of measurements.It proves that the developed method is effective in improving alloys quantitation of LIBS,and more applications are expected in other fields in the future.

关 键 词：光谱学 定量分析 免定标 自吸收校正 准光学薄态 铜锌合金 

分 类 号：O433.4[机械工程—光学工程]