Method of spherical powder from intermetallic alloy production
FIELD: technological processes.
SUBSTANCE: invention relates to production of spherical powder from intermetallic alloy. Method involves melting of cylindrical billet end from intermetallic alloy rotating about horizontal axis in spraying chamber with plasma jet arc plasmatron with enabling centrifugal spraying of melted particles and their hardening at flight in working gases medium, wherein hot working gases mixture is taken from spraying chamber, cooled down and cooled working gases mixture is supplied into spraying chamber enabling fused particles cooling, wherein hardened particles are collected in receiving bin. Cooled down working gases mixture is supplied into spraying chamber with controlled intensity and orientation by means of cooling flows formers, made in form of at least two different diameters axial sprayers, ensuring outgoing from sprayers cooling flows overlapping to make cooling zone of melted particles with controlled temperature gradient.
EFFECT: lower temperature in spraying chamber to required values, increased particles cooling rate control efficiency.
1 cl, 1 dwg
SUBSTANCE: unit includes a chamber with a workpiece accumulator and a device for their one-by-one supply for sputtering, a chamber with a workpiece rotation mechanism in the form of two supporting drive pulleys with a pressure roller and a mechanism for the longitudinal supply of the workpiece with a pusher, a fusion chamber with a plasmatron directed to the end face of the workpiece being sputtered. The chamber with the workpiece accumulator is provided with a rotary lock that separates it from the chamber with mechanisms of rotation and longitudinal supply of the workpiece. The fusion chamber is provided with a gas recirculation unit including a fan, a cooler and moisture freezing-out traps. The plasmatron is provided with a mechanism of movement in longitudinal and transverse directions relative to the workpiece, as well as a control device of a gap between the end face of the workpiece and the plasmatron. The supporting pulleys of the workpiece rotation mechanism are provided with vibration-absorbing rings contacting the workpiece, and the pusher of the longitudinal supply mechanism is made in the form of a pressure roller with a flange.
EFFECT: improving the operating reliability of the unit due to the reduction of a level of vibrations in fast mechanisms; improving the quality and yield of powder.
2 cl, 4 dwg, 1 tbl
SUBSTANCE: invention relates to metallurgy, to manufacturing of ingots aimed at further processing by hot isosatic pressing (HIP). Method to produce microingots from a melt by centrifugal disintegration involves melting of a cast block by a plasma jet formed by orifice gas supplied to the end of the fast rotating block with melt particles being produced, the latter harden into microingots when flying in the atmosphere of cold orifice gas. In the course of cast block melting, hydrogen is introduced into the plasma jet, it is provided for its ionisation and interaction of hydrogen ions with the oxides on the surface of the melt and microingots and with the orifice gas oxygen, the resulting moisture is removed from the cold orifice gas by freezing. Hydrogen is introduced into the plasma jet in the amount providing for keeping of the hydrogen residual concentration in the cold orifice gas at the level not exceeding 10 ppm.
EFFECT: quality of the produced microingots is improved due to the reduction of oxygen content in them, better mechanical properties of compact material of items.
FIELD: process engineering.
SUBSTANCE: invention relates to powder metallurgy, particularly, to production of magnesium and magnesium alloy pellets by casting. Magnesium and magnesium alloy liquid melt is dispersed via opening of rotary perforated dispersing barrel. Pellets are cooled on the mix of gel and Freon gases, Freon concentration making 3 to 7 vol. %.
EFFECT: high rate of pellets cooling, higher ductility, better mechanical properties, easier alloying.
FIELD: process engineering.
SUBSTANCE: invention relates to powder metallurgy, particularly, to continuous production of metal powder. Cast blank is fused by plasma het directed at blank end face. Melt is sprayed by rotary disc with central bore wherein blank is fed under plasma jet, said blank being rotated about its axis n one direction with the disc. Produced particles are cooled in gas. Disc is heated by used plasma jet with cold gas admixed thereto. Next blank is jointed to sprayed blank non-melting end.
EFFECT: higher yield and efficiency.
3 cl, 1 dwg
FIELD: process engineering.
SUBSTANCE: invention relates to powder metallurgy, particularly, to production of metal powders. Proposed device comprises chamber with accumulator of blanks and blank feeder, drives of blank rotation and translation, spraying chamber with plasmatron directed to blank end face and powder intake, all said components being tightly interconnected. Powder intake is equipped with blower-feeder. Spraying chamber is equipped with coarse particle deflector and sieving machine arranged ahead of intake. Drive of blank rotation is composed of hollow vertical spindle with bowl-shape disc on top face and clamping cams arranged directly under said disc. Drive of blank translation is composed of pusher arranged under spindle and aligned therewith. Spraying chamber is shaped to lens and oriented horizontally so that its axial line and those of plasmatron and spindle are aligned.
EFFECT: lower production costs, higher yield and quality.
4 cl, 2 dwg
FIELD: process engineering.
SUBSTANCE: invention relates to production of refractory metal powders, their alloys, carbides, borides, nitrides, carbonitrides, etc, to be used in fabrication of powder hard-alloy articles and wear-resistant composite coatings. Initial charge of solid loose material of preset composition is heated to 0.4-0.8 of charge fusion temperature and fed into rotary water-cooled crucible to be fused by exciting plasma arc between crucible and cathode of plasma-arc heating source. Fusion is performed in concentration of anode spot of plasma arc on crucible bottom and moving it to crucible lateral surface following the formed melt. Produced melt is sprayed in gas atmosphere in supporting melt layer on crucible lateral surfaces by concentrating anode spot on its edge under action of centrifugal forces with formation of melt drops. Said drops are crystallised in cooling. Proposed device comprises cylindrical chamber with cover accommodating bin with initial charge dispenser communicated with feeder, and plasma generator with its drive. Said chamber houses sprayer made up of rotary water-cooled crucible made from electrically conducting material with heat-insulation insert from material inert to melt material arranged on inner wall and electrically conducting material arranged on crucible bottom, heated initial charge feeder connected, and powder collection bin connected with the chamber at its bottom section.
EFFECT: reduced heat and power losses, higher process efficiency and quality of produced powder.
18 cl, 2 dwg, 2 tbl, 2 ex
SUBSTANCE: proposed method comprises producing preform of cathode target with preset chemical composition and its machining to preset geometrical sizes. Note here that for this, melted metal is poured into ceramic mould to produce electrode ingot of cylindrical shape. Then said ingot is fused by plasma to produce spherical granules with diametre varying from 50 to 400 mcm. Preset amount of spherical granules is filled in circular capsule under vacuum to produce target with cavity. Said capsule is sealed and subjected to hipping. Then capsule is unsealed and preform is cleaned by removing capsule components. Cathode target is made from alloy based on nickel or cobalt.
EFFECT: stable geometrical sizes of target preform.
12 cl, 1 tbl
SUBSTANCE: it is rotated cylindrical work around horizontal axis. It is fused butt of work and formed concave cavity with diametre equal to diametre of work and depth 0.1-0.35 of work diametre by means of changing of gas consumption through plasmatron and displacement of plasmatron relative to axis of work rotation. There are sprayed molten particles under centrifugal force action by conical surface, formed by tangent to swept surface of concave cavity.
EFFECT: reduction of porosity in sprayed particles, its improvement and decreasing of products rejection, produced from received powders and granules.
1 tbl, 3 dwg, 7 ex
SUBSTANCE: invention relates to metallurgy field, particularly to devices for metallic powder receiving. Device contains smelting chamber with heater, connected to it mechanism chamber, blanks metering device into smelting chamber, vacuum system, inlet box, tank for powder collection and located in mechanism chamber axial movement mechanism of blanks with pusher and blank swinging mechanism with driven rolls. Blank swinging mechanism is outfitted by clamping roller and bearing assemblies with gas cooling devices, electrical insulating bush of erosion-preventive tear and wear of rolling surface of bearing assemblies, temperature control sensor and level of vibration. Driven roller and clamping roller of blank swinging mechanism are installed on bearing assembly, pusher is implemented with set of nozzles on the end, directed to the side of blank feeding. Smelting chamber and mechanism chamber are connected to each other by bypass pipeline with valve.
EFFECT: range extension of sizes of received powders and homogeneity increasing of its dimension.
3 dwg, 1 tbl
FIELD: non-ferrous metallurgy industry; other industries; device for production of the granules of the non-ferrous metals.
SUBSTANCE: the invention is pertaining to production of the granules of the non-ferrous metals including the chemically active calcium or magnesium and their alloys by the centrifugal sputtering. The installation contains the melting furnace, the hermetic chamber of granulation with the cover, the electrically heated melt metal conduit, the dispenser made in the form of the perforated container with the drive of rotation, the granules collection container, the compressor and the heat exchanger. The metal conduit is made in the form of the lift tube, one end of which is located in the melting furnace with formation of the liquid metal gate out of the melt of the granulated metal, and the other end is placed in the granulation chamber. The drive of rotation of the dispenser is made in the form of the gas-turbine engine with the closed system of the gas pipelines of circulation of the noble gas from the engine into the hermetic container and further into the heat exchanger and the compressor. The engine is mounted on the hermetic container disposed in the chamber of granulation along its center coaxially with the melt metal conduit and the dispenser. The dispenser is located on the shaft of the gas-turbine engine. The invention will allow to increase the efficiency of the granules production and the outlet of the metal into the target product of any preset granulometric composition and also to reduce consumption of the noble gas.
EFFECT: the invention ensures the increased efficiency of the granules production and the output of the metal into the target product of any preset granulometric composition, and also reduction of consumption of the noble gas.
FIELD: metallurgy, namely manufacture of metallic fibers with amorphous and(or) microcrystalline structure.
SUBSTANCE: apparatus includes housing, feeder for supplying melt metal; inner and outer disc crystallizers mounted in the same axis with possibility of separate rotation of their working surfaces one relative to other; rotation drives of outer and inner disc crystallizers. Novelty is at least two calibrating devices in the form of metallic plates mounted on working surface of outer disc crystallizer. There is coaxial cone recess in working surface of inner disc crystallizer.
EFFECT: enlarged assortment of metallic fibers.
10 cl, 5 dwg, 3 ex
FIELD: metallurgy, namely methods for making metallic fibers that may be used for manufacturing composite materials.
SUBSTANCE: method comprises steps of feeding in vertical plane stream of melt metal from nozzle of feeder onto rotating cooled surface; forming on said surface from layer of melt metal discrete liquid structures of metallic fibers; cooling fibers until their crystallization; before feeding stream of melt metal, setting its temperature in range (1.04 x t - 1.18 x t), where t - crystallization temperature of melt metal. Metallic fibers are formed by two stages. At first stage liquid structures of metallic fibers are moved at rate 0.5 - 148 m/s on cooled surface. At second stage metallic fibers are subjected to percussion cooling on ribbed surface of outer disc-type cooled crystallizer at cooling rate in range 3/3 - 25.7.
EFFECT: production of metallic fibers with possibility of increasing range of their fineness at different phase content.
7 cl, 3 dwg, 3 ex
FIELD: powder metallurgy, namely manufacture of ferrites.
SUBSTANCE: wetting agent containing polyvinyl alcohol, water and powder of manganese-zinc ferrite includes in addition in order to provide uniform fraction size poly-acrylic acid, triethanolamine and octanol at next relation of ingredients, mass %: polyvinyl alcohol, 2.0 - 6.0; poly-acrylic acid, 0.5 - 2.0; triethanolamine, 1.0 - 4.0; octanol, 0.05 - 0.5; water, 30 - 65; powder of manganese-zinc ferrite, the balance.
EFFECT: enhanced uniformity of fraction size of powder.
2 tbl, 1 ex
FIELD: powder metallurgy; production of granules from melts by impact centrifugal spraying.
SUBSTANCE: proposed method includes passing the melt through hole in refractory material and crushing in vacuum chamber of hollow head whose cavity is preliminarily filled with low-melting material at low viscosity. Crystallization of drops is performed on side surface of vacuum chamber at residual pressure of no more than 0.1 kPa; these side surfaces are cooled on the outside with water. Device proposed for realization of this method includes metal receptacle and vacuum crushing chamber whose side surface is cooled with water; vacuum chamber is provided with hermetic vacuum cover with refractory guide tube inserted in it. Working surface of hollow crushing head is conical in shape and is provided with spiral blades; it is secured for free rotation. Granule receiver is made in form of two coaxial rings and is mounted on bottom of crushing chamber.
EFFECT: improved quality of granules; increased productivity; automation of sorting-out granules.
3 cl, 2 dwg
FIELD: powder metallurgy, namely manufacture of pellets and powders of uranium dioxide.
SUBSTANCE: in metallic sectional water-cooled crucible of induction furnace with frequency of induction currents 60 000 - 12 000000 Hz, polydispersional powder of uranium dioxide or uranium dioxide prepared in the same crucible by reduction of polydispersional powders of uranium oxides of higher valence is subjected to melting. Prepared melt is poured from crucible onto rotating cooled surface. Alloying components are charged into crucible before melting process. Initial material is melt due to heating charge containing reducing agent, metallic uranium, alloying component or their alloys or compounds. Reducing agent forming with oxygen volatile oxides is used. Process is realized in vacuum, reducing or inert atmosphere.
EFFECT: enhanced efficiency, increased fraction size of pellets and powders, lowered quantity of waste materials, reduced cost price of product, increased useful life period of equipment.
6 cl, 2 ex
FIELD: powder metallurgy, namely production of particles of radioactive metals or alloys.
SUBSTANCE: method comprises steps of preparing by melting melt metal or alloy mass; forming stream of such mass; spraying it and sharply cooling particles. According to invention melting is realized in inert gas atmosphere. Stream of melt metal is formed by means of nozzle. Stream is sprayed due to its contact with cooling liquid subjected to centrifugal rotation. Melt metal stream is surrounded by inert gas jacket till its contact with cooling liquid. Apparatus for performing the method includes unit for melting radioactive metal or alloy in inert gas atmosphere; units for subjecting cooling liquid to centrifugal rotation and for surrounding melt metal stream with inert gas jacket till contact of stream with cooling liquid. Stream of melt metal is formed by means of nozzle. Invention provides significantly lowered oxygen content in powder, reduced pyrophoric property of powder.
EFFECT: minimized losses of process of forming particles, decreased risk of vapor explosion.
11 cl, 1 dwg
FIELD: metallurgy, namely systems for producing metal powders.
SUBSTANCE: apparatus includes housing in the form of working chamber with controlled temperature of certain portion of its wall; unit for creating gaseous medium in volume of working chamber; electric power source; at least two electrodes; unit for continuous supply of dispersed metal. Apparatus includes in addition drive unit for rotating in horizontal plane. Said unit is provided with control circuit and electric power supply system. Working chamber is in the form of built-up sleeve having outer and inner members. Inclination angle (from outside) of wall of outer member is in range 16 - 135° relative to rotation plane. Built-up sleeve is fastened by means of bottom portion of outer member with cooled shaft of drive unit for rotating in horizontal plane. Outer metallic member of built-up sleeve has turning for passing cooling agent. Inner member of built-up sleeve is made of high-temperature ceramic material and it has chamfer formed along upper edge of sleeve. Said chamfer is inclined by angle 2 - 68° relative to rotation plane of sleeve.
EFFECT: automatic sizing of discrete particles of fibers, stable production process.
6 cl, 2 dwg, 3 ex
FIELD: metallurgy, namely manufacture of metallic fibers, wool, fiberboard.
SUBSTANCE: process comprises steps of feeding metal to dispersing zone; forming from metal surrounded by dynamic gas layer discrete particles of melt metal and simultaneously converting dynamic layer to gas-vapor mixture. Discrete particles of melt metal are formed during two stages. At first stage at least one electrode is broken by electric arc method for creating flow of discrete particles of metal; breaking formed metal particles due to their striking at rate 500 - 1100 m/s with surface of rotating dispersing disc by angle 4 - 90° relative to rotation plane. At second stage formed discrete micro-particles of metal are agglomerated till similar size on surface of rotating disc dispersing member due to acting upon them simultaneously by means of gas-vapor mixture and mechanical force field of rotating dispersing disc. Formed particles are converted to liquid structures of metallic fibers due to acting upon them by means of mechanical force field of rotating dispersing disc. Then fibers are cooled on surface of coaxial rotating crystallizing disc provided with unit for controlling temperature of its working surface. Crystallized fibers are removed from disc working surface.
EFFECT: possibility for automatic calibration of discrete fiber particles, stabilized production process.
6 cl, 3 dwg, 3 ex
FIELD: non-ferrous metallurgy, namely processes for producing pellets of magnesium or its alloys.
SUBSTANCE: method comprises steps of preparing salt mixture, loading magnesium or its alloy into melt salt mixture; agitating mixture, cooling it, milling for producing mixture of salt component and pellets; further separation of salt and metallic components in the form of pellets. Novelty is feed of milled mixture of salt component and pellets in compressed air stream; twisting flow in centrifugal chamber with tangential inlet; then removing salt component out of centrifugal chamber and depositing metallic components in the form of pellets onto bottom of centrifugal chamber; discharging pellets out of chamber. Air flow speed at inlet of centrifugal chamber is in range 50 - 400 m/s. Salt component discharged from chamber is directed to cyclone. Mixture of salt component and pellets is fed to compressed air stream by injection.
EFFECT: intensified stage of separating salt phase and pellets of magnesium or its alloys, possibility for producing improved-quality product.
4 cl, 1 ex
FIELD: production of wear-resistant materials used in composite surfacing covers.
SUBSTANCE: in accordance to method, original stock is fed into rotating cooled crucible, where it is melted down by means of plasma arc discharge. Crucible acts as anode, nitrogen is used as plasma-generating gas. Produced plasma ensures saturation of melt with nitrogen up to the above-balanced state. During spraying, drops of spherical shape are created, which during cooling are crystallized in form of granules of given granule-metric composition. Device contains cylinder-shaped chamber with a lid. Inside the chamber, spraying device is positioned, made in form of rotating current-conductive cooled crucible. Plasmatron is fastened to chamber lid above the crucible and mounted at angle β to crucible rotation axis with possible changing of aforementioned angle. Powder produced by suggested method consists of sphere-shaped granules of eutectic tungsten carbide of WC-W2C phase composition with 3,8-4,2% of mass of bound carbon content and 0,005-0,3% of mass of dissolved nitrogen. Resulting granules have granule-metric composition from 20 micrometers to 1200 micrometers, small-grained perlite structure and have increased micro-hardness and resistance to crushing force.
EFFECT: production of powder with increased resistance to wear from abrasion and impacts, increased efficiency and productivity of device due to decreased heat losses and increased working resource.
3 cl, 1 dwg, 1 tbl, 1 ex