采用电感耦合等离子体原子发射光谱法测定镁钕合金中硅、铝及铜3种杂质元素的含量。选择盐酸(1+1)溶液10 mL溶解试样(0.1 g),以克服合金的基体元素及其他共存元素的干扰为目标,选择测定上述3种元素的分析谱线依次为251.611,237.313,224.700 nm。用0.1 g高纯镁及与试样中含钕量近似的钕标准溶液作为基体,加入一定量的硅、铝和铜的标准溶液后,按试样相同的溶解方法处理并定容至100 mL。按所选仪器工作条件进行光谱测定,并制作各元素的工作曲线。硅、铝、铜的检出限(3s)依次为0.006,0.002,0.01 mg·L-1。对2个样品中的3种元素各测定6次,测定值的相对标准偏差均不大于3.7%。用标准加入法进行回收试验,测得回收率在92.0%~108%之间。

ICP-AES was applied to the determination of 3 impurity elements, i.e., Si, Al and Cu, in Mg-Nd alloys. The sample (0.1 g) was dissolved in 10 mL of HCl(1+1) and made up to 100 mL. Aiming to eliminate or avoid the interferences of matrix elements and other co-existing elements, the analytical spectral lines of 251.611, 237.313, 224.700 nm were chosen for determination of the 3 elements respectively. Using 0.1 g pure Mg with addition of Nd standard solution, to an amount near to the content of Nd in the alloy sample, as matrixes, various amounts of standard solutions of Si, Al and Cu were added to give simulated standards and treated in the same way as for the sample and values of spectral intensity were measured. Based on these data, working curves were prepared. Detection limits (3s) of 0.006, 0.002, 0.01 mg·L-1 were obtained for Si, Al and Cu respectively. Precision was tested by analyzing 2 Al-Nd alloys for the 3 elements, all the values of RSD′s (n=6) found were not greater than 3.7%. Recovery was tested by standard addition method, giving values of recovery in the range of 92.0% to 108%.