ICP-MS测定镝铁合金中杂质元素的分析方法研究

　　ICP-MS测定镝铁合金中杂质元素的分析方法研究
　　Dysprosium-iron alloy is an important additive of Nd-Fe-B permanent magnetic alloy. Dysprosium-iron alloy is requested to be more and more pure in order to meet the demand of final products. There are limited reports on analytical method of Dysprosium-iron alloy except Arc Atomic Emission Spectrometry and ICP-AES which possess such disadvantages as low sensitivity of partial elements , short of prime standard, labor intensity and rubber magnetic sheet limited application range. Methods have been proposed for the determination of impurities in dysprosium-iron alloy by ICP-MS in this paper. The methods, which are simple and rapid with accurate results, can highly meet the requirements of product inspection. In addition, economic and social benefits can also be achieved.The method has been developed for determination of rare earth impurities in dysprosium -iron alloy by ICP-MS, and the operation condition of the instrument was optimized and the correction equation was established.
　　The reliable quantitation limit are 0.2μg/g for La, Ce, Eu, Er, Tm, Yb, Y; and 0.4μg/g for Pr, Nd, Sm, Gd, Tb, Ho, Lu. The recovery of standard addition is 93-102%, RSD is less than 5%.The accuracy of the results obtained is confirmed by the determination of elements after standard addition procedure. The method is accurate, rapid and applicable to routine analysis.The method has been developed for determination of nonrare earth impurities (A1, Mg , Ni, Mn, Cr, Cu, Pb, Co, Zn, As, Cd, V) in dysprosium-iron alloy by ICP-MS. The limits of determination are all less than 1μg/g, The recovery of standard addition is 95---109%,RSD is less than 10%.The method has been developed for determination of refractory mental impurities (Ta, Nb, Zr, Hf, W, Ti, Mo) by ICP-MS after the complexation of hydrofluoric acid. The interference http://www.chinamagnets.biz/rubber/rubber-magnetic-sheet.php of salts deposition and dysprosium fluoride and the function of internal standard method have been investigated. The limits is less than 0.5μg/g. The recovery of standard addition is 93～105%.RSD is less than 10%.The influencing factors on uncertainty of measurement result for tungsten in dysprosium-iron alloy are studied by ICP-MS. The components of uncertainty of measurement result are analyzed and calculated. The expanded uncertainty of measurement result for tungsten is 12.28μtg/g when mass fraction of tungsten in the dysprosium-iron alloy is 97.5μg/g.The interference of dysprosium-iron alloy has been studied .The mass and non-mass spectra interferences of dysprosium-iron alloy have been discussed. The reasons why interferences occur as well as the removal methods have been presented.