圆棒试样直径对直读光谱分析的影响及校正方法  

A Correction Method and Affecting Factors on Element Analysis Results with Varied Diameters of Round-Bar Specimens by Electric Spark-Direct Reading Spectrometry

作　　者：石蕊[1] 郭亮[1] 赵挺[1] 应海松[1] 金献忠[1] 

机构地区：[1]北仑出入境检验检疫局,浙江宁波315800

出　　处：《岩矿测试》2014年第2期241-245,共5页Rock and Mineral Analysis

基　　金：国家质检总局科研项目资助(2012IK043)

摘　　要：在实际工作中发现,电火花直读光谱法直接分析圆棒试样时,圆棒试样直径的大小会对各元素测定结果产生影响。本文在40 mm厚合金钢板上制备出直径为Φ25 mm、Φ12 mm、Φ8 mm、Φ6 mm、Φ4 mm、Φ3 mm等系列试样,采用电火花直读光谱法研究了圆棒试样直径对元素测定的影响。结果表明,随着圆棒试样直径的减小,碳硫锰磷铬镍铜和锡的测定值偏大,硅的测定值略偏小,钼和钒的测定值偏小;各元素测定结果的变化与其挥发性和存在形态相关。为了校正各元素的测定结果,本文提出曲线插入法的校正方法,采用标准物质进行测定,各元素经过校正的测定值与标准值的绝对差值都小于相应方法规定的实验室间允差(R),证明了曲线插入校正方法的可行性,改善了直读光谱分析的准确度,可以适用于直径Φ3 mm以上圆棒试样的直接分析。The variation of element analysis results related to the diameter of round-bar specimens by Electric Spark-Direct Reading Spectrometry was uncovered during experimental work.A series of specimens,with diameters of φ25 mm,φ12 mm,φ8 mm,φ6 mm,φ4 mm and φ3 mm,were prepared from a 40 mm thick alloy steel plate.All the round-bar specimens were analyzed by using direct-reading spark spectrometry.The results indicate that the specimen with the smallest diameter has the highest content reading of C,S,Mn,P,Cr,Ni,Cu and Sn,slightly lower content reading of Si and low content reading of Mo and V.The variation of content readings is related to the volatility and occurrence form of the target element.In order to correct the results,a curve interpolation method was applied.A CRM was analyzed and corrected,the element deviation between the content result and certified value was less than the tolerance between laboratories （R）,and the feasibility of the method was confirmed.This method is suitable for round-bar specimens with more than φ3 mm in diameter.

关 键 词：电火花直读光谱法 圆棒试样直径 曲线插入法 

分 类 号：O657.31[理学—分析化学]