ELEMENTAL ANALYSIS OF FE-BASED POWDERS BY GLOW-DISCHARGE MASS-SPECTROMETRY

Glow discharge mass spectrometry (GDMS) which has mainly been develope d for bulk samples was applied to powder samples. Powders were pressed on a pure In sheet and mounted on a discharge cell for disk-shaped sa mples. The discharge condition commonly used for bulk samples was empl oyed. The surface contamination was removed by pre-sputtering for 60 m inutes. The size of particle and the density of the powder pressed on the In sheet do not affect the ratios of ion currents of analyzed elem ents to that of the matrix element. The relative sensitivity factors ( RSFs) for 21 elements (isotopes) have been determined for Fe-based pow ders. The RSFs for powders are almost equal to those for Fe-based allo ys with disk shape. The relative error of analytical values by GDMS to the chemically analyzed values was about 25% in average for trace ele ments of concentration less than 10ppm and smaller for elements of the higher concentrations.