石墨消解-电感耦合等离子体质谱法测定镍基高温合金中痕量钠和钾  

Determination of trace sodium and potassium in nickel-based superalloy by inductively coupled plasma mass spectrometry with graphite digestion

作　　者：欧阳宇[1,2] 胡净宇 王小龙[2] 杨国武 齐荣 OUYANG Yu;HU Jingyu;WANG Xiaolong;YANG Guowu;QI Rong(Central Iron and Steel Research Institute Co.,Ltd.,Beijing 100081,China;NCS Testing Technology Co.,Ltd.,Beijing 100081,China)

机构地区：[1]钢铁研究总院有限公司,北京100081 [2]钢研纳克检测技术股份有限公司,北京100081

出　　处：《冶金分析》2024年第2期24-29,共6页Metallurgical Analysis

基　　金：国家重大专项(J2019-VI-0023);国家重点研发计划(2022YFF0609301)。

摘　　要：采用电感耦合等离子体质谱法(ICP-MS)测定Na、K时,由于其轻质量数导致灵敏度较低、多原子离子质谱干扰以及极易污染而导致空白值较高。采用5 mL盐酸-1 mL硝酸-0.5 mL氢氟酸于全自动石墨消解仪中消解镍基高温合金样品,选择^(23)Na、^(39)K为待测同位素,以冷焰模式克服了多原子离子^(7)Li^(16)O^(+)、^(38)Ar^(1)H^(+)和双电荷离子^(46)Ti^(++)等质谱干扰,选用纯镍进行基体匹配、以Li为内标来校正基体效应,建立了电感耦合等离子体质谱法测定镍基高温合金中痕量Na、K的方法。对测定条件进行了优化,确定射频功率为750 W,采样深度为13.5 mm。在优化的实验条件下,Na、K校准曲线的线性相关系数均为0.9999,方法检出限分别为0.20μg/g和0.21μg/g,定量限分别为0.66μg/g和0.69μg/g。采用所建立的方法测定镍基高温合金样品中Na、K,测定结果与火焰原子吸收光谱法测定值吻合性较好,相对标准偏差(RSD,n=7)小于2.5%;加标回收率分别为98%~102%、95%~101%。During the determination of Na and K by inductively coupled plasma mass spectrometry(ICP-MS),the sensitivity was relatively low due to the light mass number of Na and K.Moreover,the mass spectral interference of polyatomic ions and the easy contamination can cause high blank value.In experiments,the nickel-based superalloy sample was digested in a fully automatic graphite digestion instrument with 5 mL of hydrochloric acid,1 mL of nitric acid and 0.5 mL of hydrofluoric acid.^(23)Na and^(39)K were selected as the isotopes to be measured.The mass spectral interference of polyatomic ions(^(7)Li^(16)O+and^(38)Ar1H^(+))and doubly charged ion(^(46)Ti^(++))was overcome through the cold flame mode.Pure nickel was selected for matrix matching and Li was used as the internal standard to correct the matrix effect.A method for the determination of trace Na and K in nickel-based superalloys by ICP-MS was established.The measurement conditions were optimized:the radio-frequency power was 750 W and the sampling depth was 13.5 mm.Under the optimized experimental conditions,the linear correlation coefficients of calibration curves for Na and K were 0.9999.The limits of detection for Na and K were 0.20μg/g and 0.21μg/g,and the limits of quantificaton were 0.66μg/g and 0.69μg/g,respectively.The established method was applied to determine Na and K in nickel-based superalloy samples,and the found results were in good agreement with those obtained by flame atomic absorption spectrometry.The relative standard deviations(RSD,n=7)were less than 2.5%,and the spiked recoveries were 98%-102%and 95%-101%,respectively.

关 键 词：镍基高温合金 电感耦合等离子体质谱法(ICP-MS) 石墨消解 钾 钠 

分 类 号：O657.63[理学—分析化学] TF031[理学—化学]