A Comparative Study of Fluorescent X-Ray and Emission Spectrometric Analysis of Pig Iron

Abstract

Fluorescent X-ray analysis and emission spectrometric analysis (quantovac) were compared each other for the determination of Si, Mn, P, S, Cu, Cr, and Ti in pig iron and a consideration was given to the effects of the metallic structure of a sample on precision and accuracy of the analytical results. The instruments used r for this study were X-ray quantometer VXQ-120, two simultixes and two vacuum quantorecorders. A pair of samples were taken into both steel and sand moulds from a spoon of metal. Some of elements the alibration standards of which were required were added into a spoon for several charges of all 50 samples.
For quantovac analysis, there was little difference in calibration curves between samples of the different moulds, while for X-ray analysis the calibration curves of Si, P, S, and Ti showed some differences which made greater as the atomic number decreased. In the samples of less than 0-40% of Si and/or more than 0.30% of Cr taken into sand mould, whose structures showed white or mottled pig iron structure, analytical values of P and S gave big errors.
Precision was in the same level for X-ray and quantovac analyses for heavy elements, but the former was superior to the latter for P and S by factor of 3 to 5. Accuracy of X-ray system was comparable to that of quantovac system.
It was concluded as the results of this study that fluorescent X-ray analysis was preferable to quantovac system for a production control analysis of pig iron from overall view points.