The use of a high temperature hollow-cathode lamp for the spectrographic analysis of steels, high temperature alloys and related materials for trace elements

Abstract

A study has been made of factors affecting the operation of high temperature hollow-cathode lamp discharges for the emission-spectrographic determination of trace elements in steels, high temperature alloys and related materials. The factors studied include electrode geometry, carrier-gas pressure and exposure times. The effect of these parameters on element sensitivity and the precision of analysis is discussed.The analysis of dissimilar alloy types has been shown to present problems associated with inter-element effects, and the magnitude of these effects is illustrated. A simple method for overcoming inter-element effects is described, involving the addition of silicon as a buffer to both samples and standards. Results by this method for the analysis of a wide variety of materials from calibration graphs based on a single set of synthetic powder standards are presented. It is possible by this technique to obtain quantitative trace-analysis results without the necessity of providing chemically analysed standards.