Determination of nitrogen and carbon in refractory nitrides and carbonitrides by means of Dumas gas chromatography

The applicability of an automated Dumas-GC method for the determination of nitrogen and carbon in refractory materials was investigated. Analyses were carried out to determine nitrogen and carbon in TiN, ZrN and Ti(C,N) using CuO, V₂O₅ and Pb₃O₄ as oxidizing additives. The reproducibility of the analyses obtained with V₂O₅ was better than ± 1 rel% for major constituents. An estimation of the accuracy of the Dumas-GC method shows that this rapid and low-cost method can compete with other methods, at least for the refractory nitrides and carbonitrides of the transition metals.