Determination of major to trace elements in metallic materials based on the solid mixing calibration method using multiple spot-laser ablation-ICP-MS

Abstract

We have developed a new analytical method for the determination of major to trace elements in metallic materials using multiple spot laser ablation (msLA)-ICP-MS. The concentration values of Cr, Co, Ni, and Cu in metallic materials were calculated from calibration curves obtained using the solid-mixing method achieved by the combination of a high-repetition rate laser and galvanometric optics. With the multiple-spot ablation procedure, two or more materials can be ablated nearly at the same time, and the calibration curve could be defined by mixing two standard materials of different concentrations. Another important feature of the method is that large amounts of samples can be ablated with the high-repetition rate lasers within short time durations, i.e. it results in a better signal to noise ratio. In this study, concentrations of Cr, Co, Ni, and Cu in 13 metallic materials (iron meteorite, stainless steels, tool steels, and low alloy steels) were measured from calibration curves obtained by aerosol mixing using the msLA-ICP-MS technique. The resulting signal intensity data exhibited good correlation with the calculated concentrations. The calculated concentration data for the analytes showed good agreement with the reference value within 10% for most of the metallic materials with analyte concentration covering dozens of % down to μg g⁻¹. The data obtained here demonstrate clearly that calibration based on the solid sample mixing can become a powerful method to determine the amounts of major to trace elements in solid materials.