APPLICATION OF ICP-OES SPECTROMETRY FOR DETERMINATION OF HIGH CONCENTRATIONS OF SILICON IN CAST IRON AND STEEL

Abstract

The study investigates the possibility of applying induced plasma atomic emission spectrometry (ICP-OES) to determine silicon content exceeding 0.5% in iron-based samples. ICP-OES spectrometry requires liquid samples. Solid samples must be dissolved prior to the analysis. Dissolution of some types of steel requires strongly oxidising mixtures of inorganic acids. In such conditions, higher silicon contents tend to form insoluble oxides. Silicon oxides, in the form of amorphous sediment, precipitate on the bottom and walls of laboratory vessels. As a result, silicon determinations are strongly underestimated. The article presents the preparation of iron matrix based solutions for the determination of silicon-high concentrations using ICP-OES spectrometry.