GB881184A - Improvements in or relating to metallo-ceramic compositions - Google Patents

Abstract

One or more metal oxides or a mixture of one or more metal oxides and one or more metalloid oxides are irradiated with 100 to 400 million Roentgens per gram to produce a metalloceramic composition. Exemplified oxides are titanium, tantalum, tungsten, vanadium, zirconium, germanium, silicon, thallium, thorium, lanthanum, gallium, uranium, indium, selenium, beryllium, molybdenum, rubidium, caesium, aluminium, cadmium, barium, calcium, manganese, nickel, chromium, copper, silver, cobalt, platinum, palladium or iron. To promote the reduction of the metal oxides to produce the composition the metallic oxide is suspended during irradiation in water or a medium which is ready oxidizable such as silicon dioxide and glycerol or sugar. Up to 3% of an oxidization/reduction catalyst such as platinum oxide, palladium oxide or vanadium oxide may be included.ALSO:One or more metal oxides or a mixture of one or more metal oxides and one or more metalloid oxides are irradiated with 100 to 400 million Roentgens per gram to produce a metalloceramic composition. Exemplified oxides are titanium, tantalum, tungsten, p vanadium, zirconium, germanium, silicon, thallium, thorium, lanthanum, gallium, uranium, indium, selenium, beryllium, molybdenum, rubidium, caesium, aluminium, cadmium, barium, calcium, manganese, nickel, chromium, copper, silver, cobalt, platinum, palladium or iron. The irradiated metallic oxide after irradiation is washed with water, centrifuged, dried, pressed and prefired at 1200 DEG -1300 DEG C., soaked for 7-10 hours at 1650 DEG C. and then slowly cooled. 2 to 10% of Cu or 5 to 15% of Co may be added to the metallo-ceramic compounds, and carbon in the form of lamp black, graphite, stearic acid, other fatty acids or paraffin may also be added to facilitate the formation of the pressed compact.ALSO:One or more metal oxides or a mixture of one or more metal oxides and one or more metalloid oxdies are irradiated with 100 to 400 million Roentgens per gram to produce a metalloceramic composition. Exemplified oxides are titanium, tantalum, tungsten, vanadium, zirconium, germanium, silicon, thallium, thorium, lanthanum, gallium, uranium, indium, selenium, beryllium, molybdenum, rubidium, caesium, aluminium, cadmium, barium, calcium, manganese, nickel, chromium, copper, silver, cobalt, platinum, palladium or iron. Germanium dioxide, silicic acid and glycerol are mixed and irradiated with substantially 100 million Roentgens per gram, lamp black added, the mixture heated to 350 DEG C. to form a hard plastic material, pulverized plastic material is mixed with a binder, the mixture compresed into a filament. A similar process of mixing molybdenum sesquioxide, silicic acid and glycerol is also described. To promote the reduction of the metal oxides to produce the composition the metallic oxide is suspended during irradiation in water or a medium which is ready oxidizable such as silicon dioxide and glycerol or sugar. The irradiated material is dried and pressed and prefired to temperatures of 1200 to 1300 DEG C., subjected to a soaking period of 1650 DEG C. for 7 to 10 hours followed by slow cooling for twelve hours. Up to 3% of an oxidization reduction catalyst such as platinum oxide, palladium oxide or vanadium oxide may be included.