摘要:
The invention concerns a composite body consisting of a hard metal, cermet or ceramic substrate body and at least one layer of a mechanically resistant material, a ceramic substance, a diamond-like layer, amorphous carbon and/or hexagonal boron nitride. The invention also concerns a method of producing this composite body, wherein, when the green compact has been dewaxed, with its pores still open and whilst it continues to be heated as from a temperature of between 600° C. and 1100° C., it is acted upon by sublimable solids and/or reaction gases which are necessary for coating purposes. The temperature of the green compact is then further increased and the latter is fully compressed by sintering, before one or more layers of the above-mentioned type is/are applied.
摘要:
A hard metal or cermet sintered body and a method of making it wherein a solid phase containing WC and a binder phase are formed together with WC platelets by direct microwave irradiation, utilizing reactive sintering to form the WC at least in part and to produce the platelets.
摘要:
A composite body of a microwave sintered composition of a cermet or hard metal as a modified surface layer which can promote the microwave sintering and can be of a thickness of 0.01 to 1 mm with a density gradually decreasingly inwardly or a thickness up to 1 mm and having locally distributed compacts therein or which can be a layer of a thickness of 1 to 10 mm of a substantially pure metal or which can have a binder metal removed to a depth of about half the grain thickness of a hard material such as WC.
摘要:
A cermet or hard metal body is formed from elemental metal, carbon and a nitrogen source such as a metal nitride or an organic nitrogen source by microwave sintering such that chemical reaction occurs with the formation of carbides and/or carbonitrides. The elemental metal, carbon and nitrogen source are mixed together and prepressed to form the green body which is subjected to the microwave radiation in reaction sintering.
摘要:
The invention relates to a device for adjusting the distribution of microwave energy density in an applicator which forms a resonator chamber and in which the radiation generated by microwave generators is guided to the applicator wall by waveguides; and to a use for this device. According to the invention, several electroconductive coupling pins (31) are used, each of these extending preferably vertically into both the waveguide chamber and the applicator resonator chamber, in order to feed in the microwaves with as little loss as possible and to enable the field distribution in the resonator chamber to be modified. The invention is especially suitable for producing a plasma.
摘要:
A method and apparatus for the heat treatment of hard metals, cermets and ceramics in a microwave sintering furnace, the material to be treated being moved together with the resonator relative to one or a plurality of microwave sources. The material to be treated is disposed in individual cassettes which, with the exception of an opening necessary for the microwave radiation, consist of material which is impermeable to microwaves and dimensioned to simultaneously form microwave resonant cavities at a microwave frequency when charged with the material.
摘要:
A method and a furnace are provided for microwave sintering of nuclear fuel. A stationary wave is generated in an antenna cavity and used to extract microwaves through slots into a resonance chamber containing the nuclear fuel. A position of the slots is adjusted in such a way that a predetermined temperature profile is produced in the nuclear fuel.
摘要:
This invention relates to a method for the thermal treatment of granular solids in a fluidized-bed reactor (1), in which microwave radiation from a microwave source (2) is fed into the reactor (1), and to a corresponding plant. To improve the utilization of energy and the introduction of the microwave radiation, a first gas or gas mixture is introduced from below through a preferably central gas supply tube (3) into a mixing chamber (7) of the reactor, the gas supply tube (3) being at least partly surrounded by a stationary annular fluidized bed (8) which is fluidized by supplying fluidizing gas. The microwave radiation is supplied to the mixing chamber (7) through the same gas supply tube (3).
摘要:
The invention concerns composites substantially consisting of: a cermet material having a binder metal phase of between 5 and 30 mass % and the remainder comprising at least one carbon nitride phase; or a hard metal with a hard material phase of between 70 and 100 %, the remainder being a binder metal phase, with the exception of a WC-Co hard metal, with up to 25 mass % cobalt as binder metal; or a powder-metallurgically produced steel. The invention further concerns a process for producing this composite. In order to improve bending strength and hardness, sintering is carried out in a microwave field.
摘要:
This invention relates to a method for the thermal treatment of granular solids in a reactor (1) with swirl chamber (4), which in particular constitutes an flash reactor or suspension reactor, wherein the microwave radiation from a microwave source (2) is fed into the reactor (1) through a wave guide, and to a corresponding plant. To avoid deposits in the wave guide, the same constitutes a gas supply tube (3), a gas stream being additionally fed through the gas supply tube (3) into the swirl chamber (4).