Some topical applications of plasma atomic spectrochemical methods for the analysis of ceramic powders

The scope of a number of plasma spectrochemical methods for the determination of the main components and impurities in ceramic powders is described. These methods meet the requirements for the analytical characterization of new structural and functional ceramics for modern industrial applications and electronic devices. For ceramic powders, spectrochemical analysis with direct methods as well as analysis subsequent to sample dissolution are discussed. Fusion is a powerful method for the dissolution of ZrO₂ ceramic powders, provided the fluxes are pure enough. For determinations in Al₂O₃, SiC and ZrO₂, it will be shown that ICP-MS is very useful. This is especially true for trace analysis after matrix removal. The latter can easily be performed on-line in the case of the analysis of Al₂O₃ powders. For direct analysis of ceramic powders, the direct insertion of samples into the plasma, spark and arc ablation, laser ablation, electrothermal vaporization and slurry nebulization are discussed. Particular attention is given to the direct analysis of ceramics in powder form (Al₂O₃, SiC, Si₃N₄, B₄, WC) using ICP-OES with slurry nebulization as well as with direct sample insertion (DSI) and with electrothermal vaporization (ETV). For the two latter methods, the use of chemical modifiers for volatile compound formation will be shown to be of great importance, and its features will be explained using thermochemical considerations.