Abstract
In the vacuum fusion analysis for the determination of oxygen in refractory metals such as titanium and zirconium, the characteristics of the bath to be used has an immediate influence on accuracy, precision of the analysis and required time for it.
In this report, a result of investigation on a vacuum fusion analysis of titanium using platinum bath is given. 2550g of platinum and 12g of tin are melted in a graphite crucible. Using this bath, keeping gas extraction temperature at 19001950°C, vacuum fusion analysis of titanium can be done continuously for 1227 samples. Time required is as short as 4050 minutes per one sample, and reproducibility is 2.27.9% as standard deviation. Speciality of the presented method is to be able to analyze a large number of sample by one set of vacuum furnace at 4060% cost of iron-tin bath method which has been previously reported by the authors. In addition, even if the operation is stopped during the analysis and the bath is cooled down, the analysis can be reopened with same precision as before by reheating of the bath and simple degassing.
The greatest difficulty for applying the method to routine analysis is the expensiveness of platinum. However, an increase of running cost is rather small, since 9597% of the platinum can be usually recovered.
