초록 ▼

Metal carbide and metal nitride powders produced by the carbothermal reduction of one or more metal oxides reacted with a binder material and a carbonaceous additive or optionally, a binder capable of supplying carbon to the reaction. The metal oxides are selected from among SiO2, Al2O3, TiO2, ZrO2,

Metal carbide and metal nitride powders produced by the carbothermal reduction of one or more metal oxides reacted with a binder material and a carbonaceous additive or optionally, a binder capable of supplying carbon to the reaction. The metal oxides are selected from among SiO2, Al2O3, TiO2, ZrO2, HfO2 and B2O3 and are combined with the binder in the presence of carbon to form granules having a controlled pore volume. The granules are then subjected to a carbothermal reduction reaction, in the presence of a nitrogen or a neutral atmosphere, to produce metal nitrides or metal carbides respectively, having an excess of carbon incorporated therein. The product is subsequently heated to react the excess carbon within the compound with oxygen from the atmosphere to form carbon monoxide gas, which may be removed by an optional exhaust system. The remaining metal carbide or metal nitride powder may then be collected and used in various applications such as the production of ceramic objects.

대표청구항 ▼

A process for forming a metal nitride powder which comprises: reacting at least one metal oxide composition with a binder and a material capable of supplying carbon to said reaction, or with a binder capable of supplying said carbon so as to produce granules having a controlled pore volume ranging f

A process for forming a metal nitride powder which comprises: reacting at least one metal oxide composition with a binder and a material capable of supplying carbon to said reaction, or with a binder capable of supplying said carbon so as to produce granules having a controlled pore volume ranging from about 0.1 to 3 cm3/g; subjecting said granules to a carbothermal reduction reaction at a temperature ranging between about 1300°-1600°C. in an atmosphere containing nitrogen or which is capable of releasing nitrogen so as to form said metal nitride powder wherein said powder contains an excess of said carbon; heating said powder so as to decarbonize said metal nitride until substantially all of said excess carbon is eliminated; and collecting said metal nitride powder in the form of particles or agglomerates, said metal nitride powder having a specific surface area of at least about 30 m2/g. A process for forming a metal carbide power which comprises: reacting at least one metal oxide composition with a binder and a material capable of supplying said carbon to said reaction, or with a binder which is capable of supplying said carbon so as to produce granules having a controlled pore volume ranging from about 0.1 to 3 cm3/g; subjecting said granules to a carbothermal reduction reaction at a temperature ranging between about 1300°and 1600°C. in a neutral atmosphere so as to form said metal carbide powder wherein said powder contains an excess of carbon; heating said powder so as to decarbonize said metal carbide until substantially all of said excess carbon is eliminated; and collecting said metal carbide powder in the form of articles or agglomerates, said metal carbide powder having a specific surface area of at least about 30 m2/g.