辉光放电质谱仪测定不锈钢中微量元素的不确定度分析

本文以不锈钢中铁(Fe)元素作为内标,采用辉光放电质谱仪测定不锈钢中锰(Mn),硅(Si),硫(S),磷(P),镍(Ni),铬(Cr),钨(W),钒(V),钼(Mo),铝(Al),钛(Ti),铜(Cu)等12种元素。讨论了测试过程中由测量重复性、样品不均匀性和标准样品本身不确定度等因素所带来的不确定度分量,计算出测定不锈钢中的12种元素百分含量的合成不确定度及扩展不确定度。研究结果表明,采用辉光放电质谱仪测定不锈钢中的12种元素含量的扩展不确定度均小于0.01%。

Uncertainty Evaluation of the Determination of Microelement in Stainless Steel by Glow Discharge Mass Spectrometry

The amounts of twelve microelements in stainless steel,i.e. Mn,Si,S,P,Ni,Cr,W,V,Mo,Al,Ti and Cu,were measured by glowdischarge mass spectrometry （GD-MS）,using Fe element as internal standard. The measurement uncertainty resulted from reproducibility of measurement,non-homogeneity of sample and uncertainty of standard material was discussed in detail. And the combined standard uncertainty and expanded uncertainty were calculated accordingly. The results indicated that the expanded uncertainty of determination of twelve microelements in stainless steel by GD-MS was smaller than 0.01%.