DIRECT SOLID SAMPLING OF NICKEL BASED ALLOYS BY GRAPHITE-FURNACE ATOMIC-ABSORPTION SPECTROMETRY WITH AQUEOUS CALIBRATION

The direct analysis of solid nickel based alloy samples was investigated using graphite furnace atomic absorption spectrometry (GFAAS) with Zeeman background correction and a Perkin-Elmer solid sampling cup accessory. Advantages of direct solid sampling include high sensitivity and reduced risk of sample contamination since no dissolution step is used. Using aqueous standards and STPF technology with Zeeman background correction, it has proved possible to analyze small chips of nickel based alloy directly. High temperature alloy standard reference materials (SRM's) were accurately analyzed for low and sub ppm concentrations of the trace metals thallium, bismuth, tellurium, selenium and lead in the alloys. Analyses were done on single alloy chips weighing between 0.5 and 4 mg with typical analytical RSD's of 6-14%. © 1990.