The determination of nitrogen in copper-titanium alloys

An experimental program on the casting of copper-titanium alloys is being conducted in this laboratory. It was suspected that nitrogen was absorbed from the atmosphere during these casting operations and possibly caused embrittlement of these alloys. An accurate means of determining nitrogen in copper-titanium alloys was therefore necessary. A rapid and accurate method is proposed for determining nitrogen in copper-titanium alloys which is satisfactory for quantities of nitrogen as low as 0.01 per cent. In the development of the procedure, a study was made of possible digestion solutions. A moderately concentrated solution of perchloric acid was found to be most practical for decomposing the sample. When solution of the sample is completed, the mixture is transferred to the flask of a micro-Kjeldahl dihtillation apparatus. Sodium hydroxide is added until the solution is distinctly alkaline, and the liberated ammonia is steam distilled into a solution of boric acid and titiated with standard acid.