ABSTRACT
Carbon and sulfur determinations by thermal evolution techniques are almost always comparative in that certified metal alloy reference materials are used to calibrate them. There are other, older, instrument designs for the thermal evolution measurement of carbon and sulfur in alloys. As with all thermal evolution techniques an accurate blank becomes more and more critical as the work approaches and enters the trace and ultratrace realm. Unlike carbon and sulfur, for which optical emission is the only viable, fundamentally distinct, alternative technique, it is possible to cross-check results for nitrogen and oxygen by a number of methodologies. Hydrogen is present in solid solution in the transition metals, such as iron, nickel, cobalt, and copper with a relatively low concentration present at saturation. Total reflection X-ray fluorescence spectrometry is a rapidly growing trace analytical technique that utilizes the familiar X-ray sources and detectors in a fundamentally different geometry.
