电感耦合等离子体原子发射光谱法测定铝合金中微量碲

Determination of Trace Tellurium Content in Aluminium Alloy byInductively Coupled Plasma-Atomic Emission Spectrometry Method

碲是新型先进铝合金的微合金化元素,可提高合金强度、塑性、耐热性和耐蚀性。针对先进铝合金研发、生产和应用过程提出的微量碲的准确、快速检验需求与国内外检测标准缺乏铝合金中碲元素分析方法的现状,基于电感耦合等离子体原子发射光谱法开展了铝合金中碲的分析方法研究。研究确定了样品消解方法,考察优化了分析谱线、观测方式、射频功率与雾化气、等离子体气和辅助气流量等光谱仪的工作参数。确定的条件参数如下,射频功率:1.20 kW,雾化气流量:0.75 L·min^(-1),等离子体气流量:12.5 L·min^(-1),辅助气流量:1.0 L·min^(-1),轴向观测方式,选择214.282 nm作碲的分析谱线。准确称取0.10 g铝合金试样,加入5.0 mL高纯水、5.0 mL盐酸和1.5 mL硝酸加热溶解后定容至100.00 mL。以0.100 g高纯铝为基体,采用基体匹配法建立铝合金中碲校准曲线溶液,校准曲线线性相关系数达0.999。方法的检出限为0.002%,定量限为0.005%,测定结果的相对标准偏差(RSD)不大于5%,方法加标回收率为96%~109%,合成样品的测定结果与理论值相符,偏倚小于GB/T 20975.25—2020规定的再现性限。该方法具有灵敏、准确、快速、绿色等优点,可用于铝合金中微量碲的分析,填补了国内外铝合金中碲元素分析的方法空白,为含碲新型先进铝合金的研发与应用过程的质量控制提供了技术支撑。

Tellurium was a trace microalloying element of new advanced aluminum alloy,which could improve the strength,plasticity,heat resistance and corrosion resistance.The research,development,production and application of aluminum alloys put forward the demand for accurate and rapid determination of trace tellurium.However,there was still a lack of analysis standards and methods for tellurium in aluminum alloys at home and abroad.In order to solve the above problems,an analytical method for tellurium in aluminum alloy has been studied and established based on inductively coupled plasma atomic emission spectrometry to solve the above problems.The digestion method of aluminum alloy sample and the working conditions of the spectrometer were studied and optimized,such as analysis of spectral line,observation mode,radio frequency power,atomization gas flows,plasma gas flow and auxiliary gas flow.The optimized condition parameters were as below:radio frequency power of 1.20 kW;atomized gas flow of 0.75 L·min^(-1),plasma gas flow of 12.5 L·min^(-1)and auxiliary gas flow of 1.0 L·min^(-1).The observation mode was set to axial direction,and Te 214.282 nm was selected as the analysis line.0.10 g of aluminum alloy sample was accurately weighed into the conical flask.Moreover,5.0 mL of high-purity water,5.0 mL of hydrochloric acid and 1.5 mL of nitric acid were added.Then heat until completely dissolved.After cooling,the test solution was diluted to 100.00 mL.The calibration curve solution of tellurium in aluminum alloy was established by the matrix matching method with 0.100 g of high-purity aluminum as the matrix.The calibration curve was a linear equation with a correlation coefficient of 0.999.The detection limit was 0.002%,and the limit of quantification was 0.005%.The optimized method was applied to the analysis of actual samples.The relative standard deviation of the determination result was no more than 5%,and the recovery rate of tellurium was 96%~109%.The determination results of the simulated sample were consistent with the theoretical value,and the bias was better than the reproducibility limit specified in GB/T 20975.25—2020.The proposed method has the advantages of sensitivity,accuracy,speed and greenness and can be used for the analysis of trace tellurium in aluminum alloys,filling the blank of the method for the analysis of tellurium in aluminum alloys at home and abroad,and providing technical support for the quality control of the development and application process of aluminum alloys containing tellurium.