Gevorkyan E. Dense and porous constructional materials from nano and submicron powders of WC, Al2O3 and SіC for multifunctional purpose

The objective of investigation -tungsten carbide nanopowders,alumina nanopowders and submicron silicon carbide nanopwders,experimental samples and materials.The aim of investigation resolved scintefic and practic problem of development new dense and porous composite materials from nano and submicron powders of WC, Al2O3 and SіC for multifunctional purpose. In investigation was used SEM,rentgenografic methods and other methods for identify chemical ,fizical and mechanical properties of developed new composite materials. In work the scientific and practical problems on creation of composite materials on a basis of nanodispersed and submicron powders of some refractory compounds (tungsten monocarbide, alumina, silicon carbide) have been decided. The structure formation mechanisms of materials received from nanоpowders of tungsten monocarbide have been established during hot pressing by a direct transmission of a current (electroconsolidation). The mathematical model allowing to establish direct influence of electrical parameters of sintering on density of refractory materials has been developed. The theoretical and practical researches carried out have allowed to develop a new tool material with high mechanical properties. The structure formation mechanisms of materials on a basis of alumina nanoparticles and alumina - tungsten monocarbide mix have been established during hot pressing by a direct transmission of a current. The kinetics of nanograin growth has been investigated and mechanisms of non-conducting electrical current alumina and some mixes of alumina with tungsten monocarbide, the laws of change of structure dispersity in dependence of sintering electrical parameters have been established. At present the question of fine porous materials' creation which find a use as filters is relevant. The processes of shaping and structure formation of foamy permeable materials on a basis of submicron particles of alumina and its some mixes have been investigated. The features of formation and reception of foamy structures from submicron particles by reactionary sintering have been established. The basic laws of sintering and optimum modes of process have been investigated. The technological process of organic binding materials' distillation after formation from submicron particles of foamy structures has been developed. For the first time in Ukraine the highly effective technological process of reception of foamy ceramic filters from alumina and its mixes has been created. The laws research of formation and reception of porous materials with tubular form from submicron powders of silicon carbide at sintering in environment of nitrogen has allowed to develop formation technology and to select optimum modes of sintering with the purpose of reception of heated filters capable to work at a rather small voltage up to 50 V. These filters can find application for clearing of soot emissions from diesel engines, and also for clearing air. The results of this investigation will use in different plants in Ukraine where using liquid metals ,air filtration and treatment hard alloys and metals.