General Alloy Analysis with a Gas Sheathed Tubular Electrode Arc

Abstract

The gas sheathed tubular electrode arc has been investigated and applied to general alloy analysis. One set of six solution standards containing 18 different elements was used. Matrix effects have been mostly controlled by using a 1 mg/ml sample or standard in a solution containing 6 mg/ml of sodium as the chloride. Fourteen different standard alloys (NBS and Alcoa) were tested, representing seven different base metals. The over-all accuracy was only about ±8% deviation from the certified value. This would permit identification of alloy type, but for greater accuracy standards more closely approximating the sample should be used. Precision for the technique is normally ±3%–4% relative standard deviation with photographic detection.