应用激光诱导离解光谱自由定标法测定黄金首饰成分初探

A Tentative Analysis of Calibration Free-Laser Induced Breakdown Spectroscopy for Quality Inspection of Gold Jewelry

利用激光诱导离解光谱自由定标法对一系列高纯度黄金样品进行定量分析与研究,初步证明了将此方法应用于黄金首饰成分测定的可行性。采用波长1 064nm的Nd∶YAG脉冲激光器激发黄金样品,波长范围为200～760nm的4CCD光纤光谱仪采集发射光谱,对Au元素质量分数范围为85.0%～99.6%的6件黄金标准样品进行激光诱导离解光谱测试。对所得黄金样品光谱中的Au,Cu,Ag三种元素分别选择合适的原子(离子)谱线代入自由定标法模型,通过所得参数拟合得到了所有元素原子(离子)的二维波尔兹曼平面曲线,并以此为基础进行元素的质量分数计算。激光诱导离解光谱自由定标法定量分析黄金样品中Au元素的质量分数与标准值的相对误差<3%。

In this paper,the feasibility of using calibration free-laser induced breakdown spectroscopy for quality inspection of gold jewelry was proved by using this method to analyze a series of gold alloy samples.The samples were induced by an Nd∶YAG pulse laser beam with a wavelength of 1 064 nm,and the atomic spectrum in the range of 200—760 nm was recorded by a fiber spectrometer with 4 CCD.Six standard gold alloy samples with the gold contents from 85.0% to 99.6% were used in the experiment.The laser induced breakdown spectra were gathered and the atomic and irons lines of elements Au,Cu,Ag in these spectra were chosen for calibration free analysis model.Saha-Boltzmann plots were obtained and content of these three elements was achieved for all samples.The relative error of the main element Au was less than 3%.