Device for electrical discharge dispersion of the metal in the bulk layer


(57) Abstract:

The invention consists in that the device for electrical discharge dispersion of metals in the bulk layer has a dielectric vessel 1, where the load to be dispersing granules of metal through the nozzle 4 in the cover above the upper edge of the dielectric walls 7. Through pipe 3 pump working fluid up until the layer of granules will not come into motion. The inclined placement of the electrodes 6 divergent ends up and the presence of narrow gaps between the lower mating edges of these electrodes, and a vertical partition 7 provides fluidization layer, mixing Groupe and sliding along the surface of the electrodes, clears the surface of the granules and the electrodes on the oxide film 2 of the RFP. f-crystals, 4 tables, 4 Il.


Same patents:

FIELD: production of powders by electric explosion of wire.

SUBSTANCE: installation includes reactor for electric explosion of wire with high-voltage and low-voltage electrodes that are connected to pulse current sources; mechanism for feeding wire to reactor; gas and powder circulation system; unit for separating gas and accumulating powder. According to invention gas and powder circulation system is in the form of tubular gas discharging pipes communicated by their one ends with reactor in front of inter-electrode gap and by their other ends - with unit for separating gas and accumulating powder. Said unit is in the form of successively connected through branch pipes expanders. Each expander is provided with powder accumulator at providing relation Si/Si+1 ≥ 1.43 where i = 1, 2…, Si - total surface area of effective cross section of tubular gas discharging pipes; S2, S3 - surface area of connection branch pipes.

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FIELD: production of nanodispersed powders of refractory inorganic materials and compounds, in particular, installations and methods for realization of plasmochemical processes of production of nanodispersed powder products.

SUBSTANCE: the installation comprises production-linked: microwave oscillator 1, microwave plasmatron 2, gas-flow former 3, discharge chamber 4, microwave radiation absorber 5, reaction chamber 6, heat-exchanger 7, filter-collector of target product (powder) 8, device for injection of the source reagents in a powdered or vapors state into the reaction chamber, the installation has in addition a device for injection of the source reagents in the liquid-drop state, it has interconnected proportioner 9 in the form of cylinder 10, piston 11 with gear-screwed electric drive mechanism 12 adjusting the speed of motion of piston 1, evaporative chamber 13 with a temperature-controlled body for regulating the temperature inside the chamber that is coupled to the assembly of injection of reagents 14 in the vaporous state and to the assembly of injection of reagents 15 in the liquid-drop state, injection assembly 14 is made with 6 to 12 holes opening in the space of the reaction chamber at an angle of 45 to 60 deg to the axis of the chamber consisting at least of two sections, the first of which is connected by upper flange 16 to the assemblies of injection of reagents, to discharge chamber 4, plasmatron 2, with valve 17 installed between it and microwave oscillator 1, and by lower flange 18, through the subsequent sections, it is connected to heat exchanger 7, the reaction chamber has inner water-cooled insert 20 rotated by electric motor 19 and metal scraper 21 located along it for cutting the precipitations of powder of the target product formed on the walls of the reaction chamber, and heat exchanger 7 is made two water-cooled coaxial cylinders 22 and 23, whose axes are perpendicular to the axis of the reaction chamber and installed with a clearance for passage of the cooled flow, and knife 24 located in the clearance, rotating about the axis of the cylinders and cleaning the working surfaces of the cylinders of the overgrowing with powder, powder filter-collector 8 having inside it filtering hose 25 of chemically and thermally stable material, on which precipitation of powder of the target product from the gas flow takes place, in the upper part it is connected by flange 26 to the heat exchanger, and in the lower part the filter is provided it device 27 for periodic cleaning of the material by its deformation, and device 28 with valve 29 for sealing the inner space of the filter. The method for production of nanodispersed powders in microwave plasma with the use of the claimed installation consists in injection of the source reagents in the flow of plasma-forming gas of the reaction chamber, plasmochemical synthesis of reagents, cooling of the target product and its separation from the reaction chamber through the filter-collector, the source reagents are injected into the flow of plasma-forming gas, having a medium-mass temperature of 1200 to 3200 K in any state of aggregation: vaporous, powdered, liquid-drop or in any combination of them, reagents in the powdered state are injected in the form of aerosol with the gas-carrier into the reaction chamber through injection assembly 35 with a hole opening into the space of the reaction chamber at an angle of 45 to 60 deg to the chamber axis, reagents in the liquid-drop or vaporous state are injected into the reaction chamber through injection assemblies 15 or 14, respectively, in the form of ring-shaped headers, the last of which is made with 6 to 12 holes opening into the space of the reaction chamber at an angle of 45 to 60 deg to the chamber axis, each of them is blown off by the accompanying gas flow through the coaxial ducts around the holes, at expenditure of the source reagents, plasma-forming gas, specific power of microwave radiation, length of the reaction zone providing for production of a composite system and individual substances with preset properties, chemical, phase composition and dispersity.

EFFECT: universality of the industrial installation, enhanced capacity of it and enhanced duration of continuous operation, as well as enhanced yield of nanodispersed powders and expanded production potentialities of the method.

20 cl, 1 dwg, 4 ex

FIELD: powder metallurgy, namely apparatuses for producing powders of electrically conducting materials.

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EFFECT: enhanced efficiency, lowered specific energy consumption, improved stability of process.

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FIELD: powder metallurgy, namely process for producing sub-micron and nanometer size aluminum powder by plasma evaporation.

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46 cl, 8 dwg, 2 tbl, 1 ex

FIELD: powder metallurgy, namely processes for producing metallic and oxide nano-particles.

SUBSTANCE: process comprises steps of placing electrodes in chamber with dielectric liquid; realizing pulse electric discharge between them for generating electric arc; measuring spacing between electrodes for fixing its value; creating flow-through motion of dielectric liquid in chamber; measuring temperature of dielectric liquid at inlet and at outlet of chamber; providing preset temperature range of dielectric liquid at inlet and at outlet of chamber due to changing flow rate of said liquid passing through chamber. Temperature difference of dielectric liquid at inlet and outlet of chamber is no more than 7°C. Invention provides increased quantity of nano-particles with fraction size 5 -50 nm.

EFFECT: enhanced quality of nano-particles.

4 cl, 1 dwg, 1 tbl

FIELD: metallurgy, namely systems for producing metal powders.

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6 cl, 2 dwg, 3 ex

FIELD: processes for preparing finely and ultra-dispersed powders of metals and alloys.

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EFFECT: simplified manufacturing process, improved ecological condition of said process, lowered power consumption.

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FIELD: inorganic protective coatings.

SUBSTANCE: invention provides preparation of chemically homogeneous powder suitable for thermal spraying. Zirconium dioxide is first subjected to electric fusion using up to 60% by weight of oxide appropriate to stabilize zirconium dioxide in tetragonal phase followed by sharp cooling of thus obtained stabilized zirconium dioxide and heat treatment to form mainly spherical hollow particles of stabilized zirconium dioxide 200 μm or less in size. Powder suitable for applying thermal barrier-forming coating onto a substrate contains morphologically and chemically uniform stabilized zirconium dioxide including spheroidized hollow particles.

EFFECT: optimized preparation process.

7 cl, 5 dwg, 1 tbl

FIELD: metallurgy.

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EFFECT: increase in thermal stability of aluminum powder to 580 °C.

2 tbl, 1 ex

FIELD: technological processes.

SUBSTANCE: invention pertains to plasma technology, and specifically to methods of obtaining metal powder. The method involves igniting a discharge between two electrodes, one of which is an anode, made from the spray material, with diameter of 10-40 mm. The cathode is in form of an electrolyte. The process is carried out under the following parameters: voltage between electrodes - 800 - 1600 V, discharge current - 750-1500 mA, distance between the anode and the electrolyte - 2-10 mm. According to the alternative method, the spray material is the anode, and the cathode is the electrolyte. The process takes place under the following parameters: voltage between electrodes - 500-650 V, discharge current - 1.5-3 A, distance between the cathode and electrolyte - 2-10 mm. The technical outcome is the increased efficiency of obtaining metal powder.

EFFECT: increased efficiency of obtaining metal powder.

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