Multielement Analysis of Steel Samples by Laser Ablation and Low-pressure Helium-ICP-MS

Abstract

A combination of laser ablation and ICP-MS offers a powerful and rapid analytical method for steel samples. The determinations of some elements (e. g., C, Si, P and S), however, are seriously disturbed by spectral interferences, mainly caused by the ambient air. In the present work, low-pressure helium-ICP-MS was applied to overcome these problems. The polished and ultrasonically cleaned steel sample was placed in an evacuated ablation cell and irradiated by a pulsed Nd/YAG laser beam (15 Hz, 150 mJ) for 30 s. The resulting sample aerosol was transported to the ICP with a stream of helium for the analysis by MS. The intensities of the analyte signals were corrected by using ⁵⁷Fe⁺ as internal standard. The analytical results obtained for C, Si, P, S, Cr, Mn, Ni and Cu were well agreed with the certified values with RSDs of 4-10% (except Si).