PECTROGRAPHIC DETERMINATION OF IMPURITIES IN CERAMIC MATERIALS FOR NUCLEAR-FUSION REACTORS

The determination of minor and trace elements in the aluminium oxide, spinel and magnesium oxide employed as ceramic materials in thermonucl ear fusion reactors has been studied. The concentration ranges are 0.0 25-1 % for Ca, Si and Y, and at the ppm level for Al, Co, Cr, Fe, Hf, K, Li, Mg, Mn, Na, Ni, Sc, Ta, Ti, V and Zr. Atomic emission spectrosc opy with direct current arc excitation and photographic detection has been employed. For most elements the use as a diluent of graphite powd er in different proportions provide suitable sensitivities and precisi ons, while for the most refractory elements the use of copper fluoride as a carrier is advisable, being necessary, in the case of magnesium oxide, a previous transformation of the sample into fluoride.