DIRECT DETERMINATION OF TRACE-METALS IN SOLID SAMPLES BY ATOMIC-ABSORPTION SPECTROMETRY WITH ELECTROTHERMAL ATOMIZERS .2. DETERMINATION OF LEAD IN STEELS AND NICKEL-BASE ALLOYS

The application of the solid sampling technique to the determination of lead in metallurgical samples is described. Comparison of non-isothermal and isothermal atomization, optimization of the atomization temperature, comparison of peak-height and peak-area measurements, and methods of extending the working range are reported. A method for the direct determination of lead in high- and low-alloy steels and in nickel-base alloys has been developed. The solid samples containing 0.2-60 μg Pb g-1, are inserted into a Varian-Techtron CRA90 graphite cup held at constant temperature (1800°C). Concentrations are calculated from the integrated peak absorbances obtained for samples and arbitrary metallurgical standards. Good agreement with certified values was obtained for all materials investigated, with a typical relative standard deviation of 7%. © 1979.