Abstract—In this work, obtaining methods of ultrafine alumina powdery composites and high temperature pressing technology of matrix ceramic composites with different compositions have been discussed. Alumina was obtained by solution combustion synthesis and sol-gel methods. Metal carbides containing powdery composites were obtained by homogenization of finishing powders in nanomills, as well as by their single-step high temperature synthesis .Different types of matrix ceramics composites (α-Al 2 O 3 -ZrO 2- Y 2 O 3, α-Al 2 O 3 - Y 2 O 3 -MgO, α-Al 2 O 3 -SiC-Y 2 O 3 , α-Al 2 O 3 -WC-Co-Y 2 O 3 , α-Al 2 O 3 - B 4 C-Y 2 O 3 , α-Al 2 O 3 - B 4 C-TiB 2 etc.) were obtained by using OXY- GON furnace. Consolidation of powders were carried out at 1550- 1750°C (hold time - 1 h, pressure - 50 MPa). Corundum ceramics samples have been obtained and characterized by high hardness and fracture toughness, absence of open porosity, high corrosion resistance. Their density reaches 99.5-99.6% TD. During the work, the following devices have been used: High temperature vacuum furnace OXY-GON Industries Inc (USA), Electronic Scanning Microscopes Nikon Eclipse LV 150, Optical Microscope NMM- 800TRF, Planetary mill Pulverisette 7 premium line, Shimadzu Dynamic Ultra Micro Hardness Tester DUH-211S, Analysette 12 Dynasizer. Keywords—α-Alumina, Consolidation, Matrix Ceramics, Powdery composites. I. INTRODUCTION ECHNOLOGIES, those imply obtainment of powdery composites and fabrication of functional ceramic materials by high temperature sintering have been used for obtaining new materials. At present, great attention is paid to the application of nanotechnologies for obtaining α-Al 2 O 3 nanopowders and nanostructural ceramic materials based on them. For obtaining ultrafine α-Al 2 O 3 , several methods were used including sol-gel process, precipitation, chemical decomposition, plasma-chemical, electrochemical, microemulsion, hydrothermal, aerosol, corrosive, polymer- precursor, high temperature oxidation etc. During T. V. Kuchukhidze is with Ilia Vekua Sukhumi Institute of Physics and Technology, Georgia, Tbilisi and with Sukhumi State University, Georgia, Tbilisi (e-mail: tinikokuchukhidze@gmail.com). N. T. Jalagonia is with Ilia Vekua Sukhumi Institute of Physics and Technology, Georgia, Tbilisi (e-mail: nati.jalagonia@gmail.com). T. V. Korkia and V. G. Gabunia are with Petre Melikishvili Institute of Physical and Organic Chemistry, Georgia, Tbilisi, (e-mail: tamrikokorkia@yahoo.com, jalabadze@gtu.ge). N. V. Jalabadze is with Georgian Technical University, Georgia, Tbilisi, (e-mail:). R.V.Chedia is with Ilia Vekua Sukhumi Institute of Physics and Technology, Georgia, Tbilisi and with Petre Melikishvili Institute of Physical and Organic Chemistry, Georgia, Tbilisi. (e-mail: chediageo@yahoo.com). transformation of aluminum hydrate phases, different forms of Al 2 O 3 (α, χ, η, δ, κ, θ, γ, ) are obtained. Only α-Al 2 O 3 is thermodynamically stable, that is obtained by gradual heating of unsustainable intermediate phases of aluminum hydroxides or alumina above 1200 o C temperature [1]-[4]. Alumina is widely applied material, for obtaining matrix ceramic composites, because they are characterized with high physical- mechanical properties, corrosion resistance, opportunity of operation at high temperatures (1400-1700 o C), radiation resistance, regulation of electrical properties in a wide range etc. Physical-mechanical properties of ceramic targets depend on powders’ sintering method. Many methods are used for consolidation of powders, including sintering of preliminary pressed powdery composite by gradual increasing of temperature, consolidation methods in micro-wave furnace, spark-plasma synthesis, sintering of powders in high frequency inductive furnace etc. [5]-[8]. In scientific researches and in practice, high temperature hot pressing furnaces with various modifications are used. Consolidation of powdery composites by hot-pressing method guarantees that materials with theoretical density will be used. One of the hot- pressing systems is high temperature (2000 o C) vacuum furnace OXY-GON (USA), which is equipped by press (30 tons). The furnace was used for consolidation of different powdery composites. The present work deals with obtaining powdery composites based on α-Al 2 O 3 and consolidation in high temperature vacuum furnace by hot-pressing method. For this purpose, simple technological scheme was developed for obtaining ultrafine alumina powders and pressing powdery composites from metal aluminum scrap and aluminum. II. EXPERIMENT A. Synthesis of alumina Synthesis of α-Al 2 O 3 was conducted by several methods: a) 15g aluminum isopropoxide was diluted in 270 ml distilled water and was heated up to 80 ˚C with permanent stirring for 6-8 h. For peptization, 1-2 ml HNO 3 was added and stirring was continued during 3 hours at 110 ˚C. Obtained suspension was placed in to porcelain bowls and dried at 120 ˚C. For obtaining α-Al 2 O 3 , powder was annealed in muffle furnace at 1200˚C. b) Aluminium nitrate (Al(NO) 3 . 9H 2 O) was dissolved in distilled water at a concentration of 0.5 mol L −1 and stirred T. Kuchukhidze, N. Jalagonia, T. Korkia, V. Gabunia, N. Jalabadze, R. Chedia Fabrication of Powdery Composites Based Alumina and Its Consolidation by Hot Pressing Method in OXY-GON Furnace T World Academy of Science, Engineering and Technology International Journal of Materials and Metallurgical Engineering Vol:10, No:7, 2016 895 International Scholarly and Scientific Research & Innovation 10(7) 2016 scholar.waset.org/1307-6892/10004975 International Science Index, Materials and Metallurgical Engineering Vol:10, No:7, 2016 waset.org/Publication/10004975