For samples with mass fraction of silicon ≤2％,0.100 0 g was dissolved with 10 mL of HC1 (1+1) solution and few drops of hydrogen peroxide.For samples with mass fraction of silicon ＞2％,0.100 0 g was dissolved first in 10 mnL of 200 g · L-1 NaOH solution,and then acidified with 15 mL of HC1 (1+1) solution.La 408.671 nm,Ce 413.765 nm and Sc 361.384 nm were selected as analysis lines.Matrix effect of aluminum was elimited using matrix matching method.The linearity ranges of La,Ce and Sc were 1.0-10.0 mg· L-1,with detection limits (3s) of 3.5,6.1,3.1 μg · L-1.The proposed method was applied to the analysis of alluminum alloy samples with mass fraction of La,Ce and Sc within 0.005 0％-0.500％,giving the sum of contents of La,Ce and Sc in consistency with the determination result of total rare elements obtained by the spectrophotometry with tribromoarsenazo as color reagent.RSDs (n=11) were less than 6.0 ％.%当样品中硅的质量分数不大于2％时,采用盐酸(1+1)溶液10 mL和数滴过氧化氢溶解0.100 0 g样品;当样品中硅的质量分数大于2％时,先用200 g·L-1氢氧化钠溶液10 mL溶解0.100 0 g样品,加入盐酸(1+1)溶液15 mL酸化.以La 408.671 nm,Ce 413.765 nm,Sc 361.384 nm作为分析线,采用基体匹配法来消除铝基体干扰.镧、铈、钪的线性范围为1.0～10.0 mg·L-1,检出限(3s)分别为3.5,6.1,3.1μg·L-1.应用该方法分析了镧、铈、钪质量分数在0.005 0％～0.500％内的铝合金样品,镧、铈、钪测定值之和与三溴偶氮胂分光光度法测得稀土元素总量相符.测定值的相对标准偏差(n=11)均小于6.0％.
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