能谱定量分析的不确定度评估

本文详细分析了能谱(EDS)定量分析过程中不确定度的来源,探讨随机变量、激发电流大小、工作距离、电子束焦距、取样点大小、电流值的可读性和电流稳定性以及ZAF因子等能谱参数对测量结果不确定度的影响。结果显示电流大小和工作距离是影响有标定量分析结果准确性的关键参数。EDS对钛非晶合金样品中Zr、Ti、Ni和Cu元素的有标定量分析结果符合定量分析要求,各元素相对扩展不确定度分别为4.68%、4.26%、5.04%和5.02%(包含因子k=2)。

Uncertainty evaluation of quantitative analysis by energy dispersive spectroscopy

In this paper,the sources of uncertainty in energy dispersive spectroscopy(EDS)quantitative analysis are analyzed in detail,and the effects of spectral parameters such as random variables,excitation current,working distance,electron beam focal length,sampling point size,readability of current value,current stability and ZAF factors on the uncertainty of measurement results are discussed.It is found that the current value and working distance are the key parameters that affect the accuracy of the results of quantitative analysis.The standard quantitative analysis results of Zr,Ti,Ni and Cu elements in titanium amorphous alloy samples meet the requirements of quantitative analysis very well.The relative expanded uncertainty of each element is 4.68%,4.26%,5.04%and 5.02%(coverage factor k=2),respectively.