Development of rapid analytical method of carbon in steels by glow discharge optical emission spectrometry

A rapid analytical method of carbon in steels by glow discharge optical emission spectrometry (GD-OES) was examined. The direct-current glow discharge was found to be more effective than the radio-frequency glow discharge for the analysis of carbon in steels because higher sputtering rates could be obtained in the direct-current glow discharge compared with the radio-frequency glow discharge. For the rapid and high precision simultaneous multi-elements analysis by GD-OES, the mechanism on a prolonged tailing of the emission intensity of carbon was investigated. We concluded that the contamination on the anode caused the gradual decrease in the emission intensity of carbon. The contaminant species could be removed more rapidly by use of the radio-frequency discharge associated with bias current conduction as a pre-burn discharge. The response time for the analysis of carbon was shortened and analytical repeatability of carbon was improved by using this new measurement program.