Stelmakh Y. The structure and properties of alumina based nanostructured materials by EBPVD

The thesis is devoted to the investigation of the structure and properties of alumina based nanostructured materials by EBPVD depending on temperature of condensation in the range of 100...1100° С and the concentration of metal component. To extend the spectrum of obtained structures and their properties methods of ionization and employment of deposition in vapor of reflected second component are considered. Microstructure of thick alumina condensates (10-100 mkm) depending on the substrate temperature is investigated on nano- and microscale level using scanning, transmission electron microscopy and X-ray diffraction. Method of deposition in vapor of reflected second component is proposed to control morphology, size and orientation of Al2O3 structural elements. The most effective components - NaCl and In are determined. Sorption characteristics of porous nanostructured alumina towards ions of metals and nonmetals are presented. The regularities of Al2O3-Co nanocomposites formation depending on the condensation temperatures are determined. It is shown that the size of the metal nanoparticles can be controlled technologically from 2...4 to 20 nm. Electrical and magnetic properties of ferromagnetic nanocomposites Al2O3-Co are presented. The percolation threshold of electrical properties is determined experimentally at 70 wt.% Co. Technological parameters of hard (HV=20-22 GPa) Al2O3-Nb and Al2O3-Mo nanocomposites synthesis are determined.