FORMATION OF ULTRAFINE PARTICLE OF OXIDE

• Main Author: FUCHIDA HIDETSUGU
• Format: Patent
• Language: English
• Published: 15.04.1988
• Subjects: CASTING; CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOIDCHEMISTRY; CHEMISTRY; COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSESC01D OR C01F; COMPOUNDS OF THE METALS BERYLLIUM, MAGNESIUM, ALUMINIUM,CALCIUM, STRONTIUM, BARIUM, RADIUM, THORIUM, OR OF THERARE-EARTH METALS; COMPOUNDS THEREOF; INORGANIC CHEMISTRY; MAKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; METALLURGY; NON-METALLIC ELEMENTS; PERFORMING OPERATIONS; PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL; POWDER METALLURGY; THEIR RELEVANT APPARATUS; TRANSPORTING; WORKING METALLIC POWDER

PURPOSE:In producing ultrafine particles of metallic oxide by heating and evaporating a metallic material in an oxygen-containing atmosphere by arc discharge between electrodes, to obtain high-purity ultrafine particles of metallic oxide, by constituting at least the cathode of carbon. CONSTITUTION:An anode 2 and a cathode 3 consisting of carbon are arranged in a vacuum container 1 and a metallic material a (e.g. Ru or Al) is put on the top of the anode 2. Then the vacuum container 1 is evacuated by a vacuum pump 9, an oxygen-containing gas is introduced through a feed pipe 5 into the container and the container 1 is filled with an oxygen-containing atmosphere. Then DC voltage is impressed to the anode 2 and the cathode 3, arc discharge is generated, the metallic material a is heated, evaporated and brought into contact with the oxygen-containing atmosphere to form ultrafine particles of metallic oxide. Consequently, since the cathode consists of a carbon electrode, the ultrafine particles of metallic oxide are not admixed with oxides of cathode like the case of tungsten cathode.