Plasma chemical synthesis of multicomponent nanopowders, their characteristics, and processing

Full text: The improvement of parameters of functional and construction materials and the development of new materials is closely related to wide application of nanosized powders and their particulate multicomponent composites as well as with detailed studies of their characteristics and processing. Owing to an increasing importance of nanoparticles many preparation methods have been developed, including mechanochemical and several liquid phase and gas phase techniques. Among these methods, a plasma technique based on the formation of products from a vapour phase provides an attractive alternative for producing multicomponent compounds or particulate composites due to mixing of components at a molecular level and relatively high production rate of a simple one-stage process.; Plasmachemical synthesis has been applied successfully to produce nitride-metals, nitride-carbide, nitride-oxide, oxide-oxide, oxide-metals by introducing and evaporation of coarse-grained commercially available powders of chemical elements, oxides, and salts in nitrogen or air plasma.; Specific surface area and average particle size of powders in the range of 20-90 m2/g and 10-100 nm, respectively, were determined depending on synthesis parameters, cooling rate of the products, and their chemical and phase composition.; The high activity, regular particle shape, and homogeneity of the produced powders allow the manufacture of dense materials with fine-grained microstructure by using pressureless sintering, hot pressing, or spark plasma sintering techniques