1985 Volume 49 Issue 8 Pages 656-662
An analytical method has been established for the determination of trace tellurium and gallium in nickel-base heat-resisting alloys by graphite-furnace atomic absorption specrrometry.
The alloy was dissolved in hydrofluoric acid nitric acid. After the solution (20 mm3) was pipetted into a L’vov platform furnace, it was ashed (Te; 1073 K-40 s, argon 5 cm3/s. Ga; 873 K-40 s, hydrogen 5 cm3/s) and atomized (Te; 2373 K-5 s. Ga; 2873 K-5 s) by using argon as a purge gas.
Synthetic calibration solutions were prepared by adding tellurium and gallium standard solutions to nickel matrix solutions which had the same acid concentrations as those of the sample solutions.
Relative standard deviation of the proposed method was within 3% at 12 ppm of tellurium and 4% at 8 ppm of gallium in nickel-base heat-resisting alloys. The limit of detection was 0.1 ppm of tellurium and 0.15 ppm of gallium, when one gram of the specimen was used.