Here, the X-ray fluorescence technique is used to determine the thickness of a coating layer as well as to analyze the surface of objects. Four metals (Ag, Cu, Fe, Pb) were covered with increasing thicknesses of gold. The measurements were performed with a commercial handheld instrument, X-SORT (Spectro). In double layers, the thickness of the covering layer was assessed by (a) the ratio between the most intense fluorescence lines of the covered element, (b) a cross-ratio between two lines of the elements in the two layers, and (c) the ordinary partial least squares (PLS) regression method. In all cases, the curves obtained could be used for the quantitative determination of the thickness. The experimental data followed the theoretical trend even though the values of the attenuation parameters were not always in agreement with the theoretical ones. Comparisons and discussion of the results of the different approaches and also with models in the literature are made. The methods studied were applied to determine the nature of the coating layers of some gilded objects and proved to be suitable for estimating the thickness of gold by providing results that were in good agreement with each other.

中文翻译：

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使用手持式 X 射线仪器测定 Ag、Cu、Fe 和 Pb 的金涂层厚度

在这里，X 射线荧光技术用于确定涂层的厚度以及分析物体的表面。四种金属（Ag、Cu、Fe、Pb）覆盖着越来越厚的金。使用商用手持式仪器 X-SORT (Spectro) 进行测量。在双层中，覆盖层的厚度通过（a）被覆盖元素的最强荧光线之间的比率，（b）两层中元素的两条线之间的交叉比来评估，以及（c） ) 普通偏最小二乘 (PLS) 回归方法。在所有情况下，获得的曲线可用于厚度的定量测定。尽管衰减参数的值并不总是与理论值一致，但实验数据遵循理论趋势。对不同方法的结果以及与文献中的模型进行了比较和讨论。所研究的方法被应用于确定一些镀金物体的涂层性质，并通过提供相互吻合的结果证明适用于估计金的厚度。