Analysis of Rotor Steels for Residual Elements

Abstract

The general approaches to the analysis of rotor steels for antimony, arsenic, tin, lead, bismuth, selenium, tellurium, aluminum, and copper at the 15 ppm level are evaluated. Chemical methods are in existence but are slow. Polarography, with some further development, would also provide usable techniques which would be slow. The instrumental methods optical emission, X-ray fluorescence and atomic absorption do not yield adequate results upon direct application to the specimen. However, with suitable concentration techniques, these methods show considerable promise for rapid analysis of rotor steels. A number of concentration techniques are discussed. Of these, acid precipitation of the sulfides appears to be the best approach. Spark source mass spectrometry, while quite sensitive, is not yet developed to the point of supplying rapid, precise, and accurate quantitative analyses.