材料期刊网

研究了由于高温合金中Mo的存在而对痕量元素Cd和Te产生的难熔多原子离子质谱干扰,考察了电感耦合等离子体质谱的高频功率、雾化气流速及离子透镜参数等因素对减小或消除~(95)MoO~+、~(94)MoO_2~+干扰的影响.通过反复试验,确立了基于~(95)MoO~+峰在~(111)Cd处所产生的等效浓度值与Mo含量间存在着二元线性关系的数学校正公式;~(94)MoO_2~+峰对~(126)Te的干扰则通过各同位素间的丰度比例关系进行校正.试验表明,采用所建立的数学校正法可以很好地校正高温合金中Mo产生的~(95)MoO~+、~(94)MoO_2~+干扰.Cd和Te的测定下限分别为0.08μg/g和1.0μg/g.方法应用于Mo的质量分数为2%的高温合金标准物质中1～10 μg/g痕量Cd和0.5～100 μg/g痕量Te的测定,测定值与标准值吻合较好,RSD小于20%.

The refractory oxide ion interference of Mo on trace Cd and Te in superalloy has been investigated in detail. By investigating the appropriate ICP-MS operational parameters such as RF power,gas flow rate, ion lens, etc, the interferences of ~(95)MoO~+ and ~(94)MoO_2~+ was minimized. On the basis of specific binary linear relationship between ~(111)Cd equivalent concentration value produced by ~(95)MoO~+ peak and Mo content, a mathematic correction formula has been established in the repeated testings.Whereas, the interference from ~(94)MoO_2~+ peak on ~(126)Te was corrected by proportional relationship among isotopes. It was shown experimentally that the interference of ~(95)MoO~+ and ~(94)MoO_2~+ produced by Mo in superalloy could be corrected well by the established mathematic correction method. The limits of quantitation were 0.08μg/g for Cd and 1.0μg/g for Te. In the application of proposed method to determine 1-10 μg/g CA and 0. 5-100 μg/g Te in superalloy containing 2%(mass fraction) Mo, the determination value was in good agreement with the certified value, with RSD less than 20%.