DETERMINATION OF IMPURITIES IN SINTERED ELECTRONIC CERAMICS BY INDUCTIVELY-COUPLED PLASMA-ATOMIC EMISSION-SPECTROMETRY FOLLOWING ACID DECOMPOSITION

Several sample decomposition methods were examined to determine additives and trace impurities in sintered electronic ceramics (lead zirconate titanate, zinc oxide, and barium titanate). Any sample pulverization made the samples severely contaminated, and hydrochloric acid extraction to remove the contaminants affected the analytical results of both trace impurities and major components in the sample. A lump (about 0.3 g) of sintered lead zirconate titanate sample was decomposed with a mixture of 1 ml of hydrofluoric acid, 9 ml of nitric acid, and 40 ml of water in a Teflon sealed vessel at 90-degrees-C. Similarly about 0.3 g of sintered zinc oxide sample was decomposed with 10 ml of hydrochloric acid in the vessel at 90-degrees-C, and about 0.3 g of sintered barium titanate sample was decomposed with 15 ml of hydrochloric acid in a Teflon pressure vessel at 200-degrees-C. The proposed methods were applied to some commercial samples, and the additives and impurities (20 elements in the lead zirconate titanate samples, 25 elements in the zinc oxide samples, and 20 elements in the barium titanate samples) were determined by inductively coupled plasma atomic emission spectrometry. (C) 1994 Academic Press, Inc.