Improved Quantitative Analysis of Metals by Spark Source Mass Spectrography

Attempts have been made to improve the precision and accuracy of the analysis of metals performed with spark source mass spectrograph by using some standard samples(aluminum, steel, copper and lead matrix)that contained impurities in concentrations ranging from a few thousan down to ten ppm. Reproducibility expressed in terms of coefficient of variation of the analytical results obtained on repeated exposures can attain 5 to 15 per cent(Tables 1 through 4)provided that all source oonditions are maintained constant, especially the spark gap at a rather large value of ca. 50μ and all plots for calculation curves are corrected for line width variation. From the analytical results thus obtained and further subjected to correction for mass dependence of emulsion sensitivity, the relative sensitivity factors of impurity elements have been. determined at the values ranging from 0.48 to 3.6(Fe=1)(Table6. cf. Table5). The experimental relative sensitivity factors agree within ± 30% with the values calulated by the relation proposed by Kai et al. in which the sensitivity factor of an element is inversely proportional to the product of its ionization potential and sublimation energy(Fig.4).