The optimization of measuring condition for the determination of carbon and nitrogen in steels by means of the glow discharge mass spectrometry (GDMS) has been studied. A double focusing glow discharge mass spectrometer, Fisons Instruments (UK) VG 9000, was used. A disk sample were dry-polished with 120-grit zirconium oxide endless-paper and preliminary exposed to glow discharge for 30 min in the discharge cell. The optimum values of discharge parameters and the suitable size of tantalum front mask were examined. The relative sensitivity factor (RSF) of each analyte was evaluated by analyzing the five standard reference materials: IARM CRMs and the high alloy steels prepared in our Institute. The average RSF-values obtained were 2.493 for carbon and 26.34 for nitrogen. The regression analysis for nitrogen showed that the slope of regression line for each alloy types was different. The concentration of matrix element required was determined by the fundamental parameter/X-ray fluorescence spectrometry. The GDMS analytical value of each analyte in high tensile steel HT80 was in good agreement with chemical analytical values.
