The present manuscript deals with the utility of the calibration-free LIBS and calibration curve methods for the compositional study of different alloys using laser-induced breakdown spectroscopy (LIBS). In the process of alloying in the smelting industry, metal concentration in different alloys affects the physical and chemical properties of the final products. Therefore, LIBS can be used as an efficient quantitative analysis tool for online monitoring of the quality of the products. This is because LIBS can be performed online, in situ, without any pre-processing, and need no sample preparation for the compositional analysis of any type of materials present in any phase (solid, liquid, gas or even molten alloys in the industries). In the present study, four alloys (three copper and one iron-based alloy) consisting of Cu, Al, Zn, Ni, Fe, Cr and Mn as major and Sn and Si as minor elements were selected for the study using calibration-free laser-induced breakdown spectroscopy (CF-LIBS) and calibration curve method i.e. partial least square regression (PLSR). For the CF-LIBS method, the temporal delay has been optimized in order to satisfy the optically thin and local thermal equilibrium (LTE) condition of the plasma. For the PLSR method, different regions of the strongest emission lines of constituents have been selected for quantitative analysis. The study of time-resolved LIBS spectra and the variation of plasma parameters with respect to the delay time is also discussed. The utility of the combined technique of CF-LIBS with the PLSR method for rapid monitoring and quality assessment of desired material/products without any sample pretreatment, thus reducing the cost of the analysis, is presented in this paper.

中文翻译：

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使用 LIBS 结合化学计量学方法对铜和铁基合金进行成分分析。

本手稿涉及免校准 LIBS 和校准曲线方法在使用激光诱导击穿光谱 (LIBS) 不同合金成分研究中的实用性。在冶炼工业的合金化过程中，不同合金中的金属浓度影响最终产品的物理和化学性能。因此，LIBS可以作为一种高效的定量分析工具，用于产品质量的在线监测。这是因为 LIBS 可以在线、原位进行，无需任何预处理，并且无需样品制备即可对任何相（固体、液体、气体甚至工业中的熔融合金）中存在的任何类型材料进行成分分析。 。在本研究中，采用免校准方法选择了四种合金（三种铜和一种铁基合金）进行研究，其中Cu、Al、Zn、Ni、Fe、Cr和Mn为主要元素，Sn和Si为次要元素。激光诱导击穿光谱（CF-LIBS）和校准曲线法，即偏最小二乘回归（PLSR）。对于CF-LIBS方法，时间延迟已经过优化，以满足等离子体的光学薄和局部热平衡（LTE）条件。对于PLSR方法，选择了成分最强发射线的不同区域进行定量分析。还讨论了时间分辨 LIBS 光谱和等离子体参数随延迟时间变化的研究。本文介绍了 CF-LIBS 与 PLSR 方法相结合的技术，可用于快速监测和质量评估所需材料/产品，无需任何样品预处理，从而降低分析成本。