能量色散X射线荧光光谱法测量钢铁中的铅

研究了采用能量色散X射线荧光光谱法测定钢铁中Pb含量。研究表明，测试过程中FeKα系谱线和峰对测试有严重干扰。分析了和峰形成的机制并建立和峰计算数学模型，通过计算获得和峰出现概率，并对和峰出现的概率进行了实验验证。建立了和峰校正工作曲线并对未知样品进行测试，方法用于钢铁样品中Pb元素的分析，测量结果与原子吸收光谱法分析结果相符，方法检出限为24.1 μg/g。对铅含量为170 μg/g的标准样品测定12次，相对标准偏差为3. 26%。

Determination of lead in iron and steel by energy dispersive X-ray fluorescence spectrometry

The content of Pb element in iron and steel has been investigated in detail by energy dispersive X-ray fluorescence spectrometry (EDXRF). It is showed that, FeKα sum-peak was the main interference factor affecting the accuracy of the testing. The formation mechanism of the sum-peak was analyzed, and a mathematical model was established. By calculating the occurrence probability of sum-peaks was obtained and experimentally verified. The sum-peak correction working curve (SPCWC) was established and used for the determination of Pb in iron samples, and the results were consistent with those from atomic absorption spectrometry (AAS). The detection limit of the method was 24.1 μg/g．Twelve times determinations for standard sample with lead mass fraction of 170 μg/g were conducted, and the relative standard deviation (RSD) obtained was 3.26 %.