CN206966635U - High frequency plasma heater for high-temperature metal powder nodularization - Google Patents
High frequency plasma heater for high-temperature metal powder nodularization Download PDFInfo
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- CN206966635U CN206966635U CN201720672040.XU CN201720672040U CN206966635U CN 206966635 U CN206966635 U CN 206966635U CN 201720672040 U CN201720672040 U CN 201720672040U CN 206966635 U CN206966635 U CN 206966635U
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Abstract
For the high frequency plasma heater of high-temperature metal powder nodularization, it is related to catalytic behavior of materials technical field；Including induction coil, electric discharge confinement tube, central gas confinement tube, outer shroud rotation gas part, center rotation gas part, the seal of tube that dusts fastening seat, high pressure water cooling discharge tube, faraday cup and nozzle；Outer shroud rotation gas part is fixedly mounted on faraday cup upper surface；Center rotation gas part level is fixedly mounted on the upper surface of outer shroud rotation gas part；The seal of tube that dusts fastening seat is fixedly mounted on the upper surface of center rotation gas part；Central gas confinement tube is fixedly mounted at faraday cup axle center；Electric discharge confinement tube stretches into faraday cup, and one end is fixedly mounted on the upper surface of faraday cup；High pressure water cooling discharge tube stretches into electric discharge confinement tube；Induction coil is fixedly mounted on the outside of electric discharge confinement tube；Nozzle is fixedly mounted on faraday cup lower surface；The utility model quenching speed is high；Product soilless sticking；Possess the longer reaction zone residence time；Particle size is evenly distributed, Oxygen potential is high.
Description
Technical field
A kind of catalytic behavior of materials technical field is the utility model is related to, particularly one kind is used for high-temperature metal powder
The high frequency plasma heater of nodularization.
Background technology
The 3D printing RP technique of Metal and Alloy part, be following near-net-shape technology the main direction of development it
One.Meanwhile the development of 3D printing technique it is also proposed higher requirement to the granularity and pattern of basic material powder, the technology will
Ask that the powder shape that good powder flowbility, loose dress and tap density are high, prepared by traditional powder-making technique is irregular, poor fluidity, it is difficult
To meet 3D printing technique requirement, and purity is high, spheroidization ratio height, good fluidity, and the appropriate spherical powder of grain size can be with
Meet this requirement well, therefore, granularity is fine, the technology of preparing of controllable high pure spherical metal or alloy powder with it is special
Equipment turns into the main direction of development of new material and equipment.
The preparation method of spherical powder is broadly divided into Physical and chemical method.Wherein, the spherical powder knot that prepared by Physical
Structure is fine and close, apparent density is high.Mainly include atomization and plasma method.Liquid phase method, which prepares spherical powder, mainly includes spraying heat
Decomposition method, carbonyl process and sol-gal process etc..
Atomization is to be impacted with the fluid (atomizing medium) quickly moved or otherwise break metal or alloy liquid
The broken spherical powder preparation method for being fine drop, being followed by condensed into solid powder.Atomization production efficiency is high, and cost is low, is
The good method at completely alloyed powder end is produced, is widely used in the preparation of the metal and alloy powder of low melting point.But the party
Powder present situation made from method is complicated, it is difficult to 20 μm of particle diameter ＜ attritive powder is made, it is difficult to high spheroidization ratio is obtained, and not
It is adapted to the preparation of refractory metal.
Spray heating decomposition be stoichiometrically prepare needed for metal salt solution and be used as presoma, formed carefully through atomization
Droplet is carried along into high temperature reaction stove by carrier gas, and the evaporation of drop moment solvent, solute are precipitated and done in high temperature environments
It is dry, while metal salt is thermally decomposed, and required powder particle is obtained through collection system.This method technique is simple, cost is low, in oxide
Powder, ceramic powders, metallic composite, the preparation field of nano composite powder are used widely, but party's chemistry owned by France
Preparation method, more serious pollution problem be present, and be also not suitable for the preparation in high-temperature metal or alloy spherical powder.
Sol-gel process (Sol-Gel) is that ester type compound or metal alkoxide are dissolved in organic solvent to be formed uniformly
Solution, then colloidal sol is formed, then material requested is made through handling process such as drying and calcination by hydrolysis, condensation chemical reaction.
Carbonyl process is to produce metal dust using the process of the thermal dissociation of carbonyl compound, suitable for magnesium-yttrium-transition metal (Fe,
Co, Ni) and high melting-point metal (Cr, W, Mo) powder preparation, the powder size fine uniform of preparation, have very high pure
Degree, but easily there are serious agglomeration traits.
Utility model content
The purpose of this utility model is the above-mentioned deficiency for overcoming prior art, there is provided for high-temperature metal powder nodularization
High frequency plasma heater, dystectic metal or alloy material can be melted；It is high to be quenched speed；Product soilless sticking；Possess more
The long reaction zone residence time；Particle size is evenly distributed, Oxygen potential is high.
Above-mentioned purpose of the present utility model is achieved by following technical solution：
For the high frequency plasma heater of high-temperature metal powder nodularization, including induction coil, electric discharge confinement tube, central gas
Confinement tube, outer shroud rotation gas part, center rotation gas part, the seal of tube that dusts fastening seat, high pressure water cooling discharge tube, faraday cup and nozzle；
Wherein, faraday cup is hollow cylindrical structure；Faraday cup is as heater housing axially vertical placement；Outer shroud rotation gas part is horizontal
It is fixedly mounted on the center of faraday cup upper surface；Center rotation gas part level is fixedly mounted on the upper table of outer shroud rotation gas part
Face；The seal of tube that dusts fastening seat is fixedly mounted on the upper surface of center rotation gas part；Central gas confinement tube is hollow columnar structures；
Central gas confinement tube is fixedly mounted at faraday cup axle center vertically, and the top of central gas confinement tube stretch out faraday cup with it is outer
Ring rotation gas part connection；Electric discharge confinement tube is hollow cylindrical structure；Electric discharge confinement tube is axially fixed installed in faraday cup axle
At the heart；High pressure water cooling discharge tube is hollow tubular structure, and high pressure water cooling discharge tube sequentially passes through seal of tube fastening of dusting from top
Seat, center rotation gas part, outer shroud rotation gas part and central gas confinement tube, stretch into electric discharge confinement tube；Induction coil is fixedly mounted on electric discharge
The outside of confinement tube；Nozzle is fixedly mounted on the center of faraday cup lower surface.
In the above-mentioned high frequency plasma heater for high-temperature metal powder nodularization, the bottom of the electric discharge confinement tube with
Nozzle connects；The top for confinement tube of discharging is connected with outer shroud rotation gas part；Induction coil is equidistantly coaxially wrapped in electric discharge confinement tube
It is outside.
In the above-mentioned high frequency plasma heater for high-temperature metal powder nodularization, the induction coil is hollow knot
Structure, hollow space are circulating cooling aquaporin.
In the above-mentioned high frequency plasma heater for high-temperature metal powder nodularization, the upper outer wall cast tree of induction coil
Fat set；The inwall of resin set and the outer wall of electric discharge confinement tube form annular cooling water passage.
In the above-mentioned high frequency plasma heater for high-temperature metal powder nodularization, resin set inwall and electric discharge confinement tube
The spacing of outer wall is 2-6mm.
In the above-mentioned high frequency plasma heater for high-temperature metal powder nodularization, the level of the nozzle interior opening
Sectional area and the ratio between the horizontal sectional area for confinement tube of discharging are not less than
In the above-mentioned high frequency plasma heater for high-temperature metal powder nodularization, the lower surface of central gas confinement tube with
The upper surface of the circle of induction coil first is concordant；The lower surface of high pressure water cooling discharge tube be located at the circle of induction coil first and the 3rd circle it
Between.
It is horizontal in the middle part of the above-mentioned high frequency plasma heater for high-temperature metal powder nodularization, the center rotation gas part
Position is provided with central gas air intake duct；Horizontal level is provided with outer shroud gas air intake duct in the middle part of outer shroud rotation gas part；Confinement tube of discharging
Outer wall is provided with cooling-water duct.
In the above-mentioned high frequency plasma heater for high-temperature metal powder nodularization, the dielectric gas of heater is including outer
Ring gas, central gas and carrier gas；Wherein, outer shroud gas enters heater by the outer shroud gas air intake duct of outer shroud rotation gas part；Central gas is led to
The central gas air intake duct for crossing center rotation gas part enters heater；Carrier gas and high-temperature metal powder are entered by high pressure water cooling discharge tube
Heater.
In the above-mentioned high frequency plasma heater for high-temperature metal powder nodularization, the carrier gas is argon gas.
The utility model has the following advantages that compared with prior art：
(1) working gas of the present utility model is divided into outer shroud gas, central gas and carrier gas three parts respectively in rational position
Into heater, the ionization effect of heater can be ensured, the enthalpy of high-temperature plasma flame stream is improved, strengthen to high-temperature metal
The heating effect of powder；
(2) induction coil is cast in resin set in the utility model, and fixation is played to induction coil, is avoided simultaneously
The problem of coil turn-to-turn gas is ionized the starting the arc；
(3) circular passage is formed between induction coil resin set inwall and electric discharge constraint pipe outer wall in the utility model, can
Electric discharge confinement tube is cooled down by cooling water, ensure that electric discharge confinement tube can work long hours without being burnt by hot flame stream
Damage；
(4) heater electric discharge confinement tube is ceramic material in the utility model, improves the intensity of electric discharge confinement tube, uses
Long lifespan.
Brief description of the drawings
Fig. 1 is the sectional view of the utility model heater.
Embodiment
The utility model is described in further detail with specific embodiment below in conjunction with the accompanying drawings：
It is the sectional view of heater as shown in Figure 1, as seen from the figure, the high frequency plasma for high-temperature metal powder nodularization adds
Hot device, including induction coil 1, electric discharge confinement tube 2, central gas confinement tube 3, outer shroud rotation gas part 4, center rotation gas part 5, discharge tube are close
It is tamping solid seat 6, high pressure water cooling discharge tube 7, faraday cup 8 and nozzle 9；Wherein, faraday cup 8 is hollow cylindrical structure；Farad
Cage 8 is as heater housing axially vertical placement；The level of outer shroud rotation gas part 4 is fixedly mounted in the upper surface of faraday cup 8
Heart position；The level of center rotation gas part 5 is fixedly mounted on the upper surface of outer shroud rotation gas part 4；The seal of tube that dusts fastening seat 6 is fixedly mounted
The upper surface of rotation gas part 5 at center；Central gas confinement tube 3 is hollow columnar structures；Central gas confinement tube 3 is fixedly mounted vertically
At the axle center of faraday cup 8, and the top of central gas confinement tube 3 is stretched out faraday cup 8 and is connected with outer shroud rotation gas part 4；Central gas
The lower surface of confinement tube 3 is concordant with the upper surface of the circle of induction coil 1 first, and its purpose of design is to isolate outer shroud gas and central gas,
Central gas is constrained, is diffused again when making it to heater region of discharge；The lower surface of high pressure water cooling discharge tube 7 is located at
Between the circle of induction coil 1 first and the 3rd circle so that from discharge tube 7 spray metal or alloy powder be directly entered high temperature etc. from
Daughter flame stream core space；Discharge tube 7 is tube shell type structure, and inner casing is wear-resistant metal material, and guarantee inwall is washed away by powder still to be had
Longer service life, shell are the good material of heat conduction, are cooled down between housing by high-pressure cooling water, prevent that outer wall is high
Warm plasma gas air-flow scaling loss.The pressure being designed to realize in control heater of nozzle 9 and the length of plasma flame stream
Degree.
Electric discharge confinement tube 2 is hollow cylindrical structure；Electric discharge confinement tube 2 is ceramic material, can ensure confinement tube of discharging
Intensity, increase the service life；Electric discharge confinement tube 2 is axially fixed at the axle center of faraday cup 8；Confinement tube 2 of discharging
Bottom is connected with nozzle 9；The horizontal sectional area of the inside opening of nozzle 9 and the ratio between the horizontal sectional area for confinement tube 2 of discharging are not less thanThe top for confinement tube 2 of discharging is connected with outer shroud rotation gas part 4；Induction coil 1 is equidistantly coaxially wrapped in the outer of electric discharge confinement tube 2
Portion.High pressure water cooling discharge tube 7 is hollow tubular structure, and high pressure water cooling discharge tube 7 sequentially passes through seal of tube fastening of dusting from top
Seat 6, center rotation gas part 5, outer shroud rotation gas part 4 and central gas confinement tube 3, stretch into electric discharge confinement tube 2；Induction coil 1 is fixedly mounted
In the outside of electric discharge confinement tube 2；Nozzle 9 is fixedly mounted on the center of the lower surface of faraday cup 8.
Wherein, induction coil 1 is hollow structure, and hollow space is circulating cooling aquaporin.The upper outer wall of induction coil 1 pours
Note resin set 10；The inwall of resin set 10 and the outer wall of electric discharge confinement tube 2 form annular cooling water passage；Resin cover 10 inwalls with
The spacing of the electric discharge outer wall of confinement tube 2 is 2-6mm.Resin covers 10 one side and fixation, another aspect resin set is played to coil
Cooling-water duct is formed between inwall and the electric discharge outer wall of confinement tube 2, recirculated cooling water is passed through and electric discharge confinement tube 2 is cooled down, put
Electric confinement tube 2 works long hours without by high temperature gas flow scaling loss in heater.
The middle part horizontal level of center rotation gas part 5 is provided with central gas air intake duct；The middle part horizontal level of outer shroud rotation gas part 4 is set
There is outer shroud gas air intake duct；The outer wall of electric discharge confinement tube 2 is provided with cooling-water duct；The dielectric gas of heater include outer shroud gas,
Central gas and carrier gas；Wherein, outer shroud gas enters heater by the outer shroud gas air intake duct of outer shroud rotation gas part 4；Central gas is in
The central gas air intake duct of heart rotation gas part 5 enters heater；Carrier gas and high-temperature metal powder are entered by high pressure water cooling discharge tube 7 to be added
Hot device；Carrier gas is argon gas.
Plasma spheroidization treatment technology is the hot environment using hot plasma, carrier gas by powder be sent into high temperature etc. from
In daughter, surface (or overall) melting after powder particle absorbs heat rapidly, and spherical droplets are polycondensed into the presence of surface tension,
Quenching solidifies and is fixed up spherical after into cooling chamber, so as to obtain spherical powder.Plasma melting and spheroidizing technology quilt
It is considered to obtain fine and close, the most effective means of regular spherical particle.Plasma spheroidization treatment technology swashs according to plasma
Originating party formula can be divided into direct-current plasma and the major class of catalytic behavior of materials two.High-frequency plasma spheroidising technology has
Advantages below：(1) temperature field of plasma is more than 5 times of chemical combustion, can melt dystectic metal or alloy material
Material；Meanwhile plasma temperature distribution is relatively uniform flat；(2) it is high (- 105K/S) to be quenched speed；(3) product soilless sticking, production
Product purity is high.Because whole process is in continuous, contactless state, and high-frequency plasma does not have electrode, thus can
To avoid product from introducing impurity, high-purity product can be obtained, three-protection design is simple；(4) relative to other plasma techniques,
The speed ratio of high-frequency plasma and plasma torch flame stream is relatively low, therefore possesses the longer reaction zone residence time, and this is to powder
It is highly beneficial that the heat absorption at end, which dissolves,；(5) particle size be evenly distributed, Oxygen potential it is high.By the control to parameter, can obtain
To the product of Oxygen potential more than 90% and technological process it is short, continuous, easily-controllable.
The content not being described in detail in the utility model specification belongs to the known technology of those skilled in the art.
Claims (10)
1. the high frequency plasma heater for high-temperature metal powder nodularization, it is characterised in that：Including induction coil (1), electric discharge
Confinement tube (2), central gas confinement tube (3), outer shroud rotation gas part (4), center rotation gas part (5), the seal of tube that dusts fastening seat (6), height
Press water cooling discharge tube (7), faraday cup (8) and nozzle (9)；Wherein, faraday cup (8) is hollow cylindrical structure；Faraday cup
(8) as heater housing axially vertical placement；Outer shroud rotation gas part (4) level is fixedly mounted on faraday cup (8) upper surface
Center；Center rotation gas part (5) level is fixedly mounted on the upper surface of outer shroud rotation gas part (4)；The seal of tube that dusts fastening seat (6)
It is fixedly mounted on the upper surface of center rotation gas part (5)；Central gas confinement tube (3) is hollow columnar structures；Central gas confinement tube
(3) be fixedly mounted on vertically at faraday cup (8) axle center, and the top of central gas confinement tube (3) stretch out faraday cup (8) with it is outer
Ring rotation gas part (4) connection；Confinement tube of discharging (2) is hollow cylindrical structure；Electric discharge confinement tube (2) is axially fixed installed in method
Draw at cage (8) axle center；High pressure water cooling discharge tube (7) is hollow tubular structure, and high pressure water cooling discharge tube (7) is worn successively from top
The seal of tube fastening seat (6) that dusts, center rotation gas part (5), outer shroud rotation gas part (4) and central gas confinement tube (3) are crossed, stretches into electric discharge about
Beam tube (2)；Induction coil (1) is fixedly mounted on the outside of electric discharge confinement tube (2)；Nozzle (9) is fixedly mounted on faraday cup (8)
The center of lower surface.
2. the high frequency plasma heater according to claim 1 for high-temperature metal powder nodularization, it is characterised in that：Institute
The bottom for stating electric discharge confinement tube (2) is connected with nozzle (9)；The top of electric discharge confinement tube (2) is connected with outer shroud rotation gas part (4)；Sense
Coil (1) is answered equidistantly coaxially to be wrapped in the outside of electric discharge confinement tube (2).
3. the high frequency plasma heater according to claim 2 for high-temperature metal powder nodularization, it is characterised in that：Institute
It is hollow structure to state induction coil (1), and hollow space is circulating cooling aquaporin.
4. the high frequency plasma heater according to claim 3 for high-temperature metal powder nodularization, it is characterised in that：Sense
Answer the upper outer wall casting resin set (10) of coil (1)；The inwall of resin set (10) and the outer wall of electric discharge confinement tube (2) form annular
Cooling-water duct.
5. the high frequency plasma heater according to claim 4 for high-temperature metal powder nodularization, it is characterised in that：Tree
The spacing of fat set (10) inwall and electric discharge confinement tube (2) outer wall is 2-6mm.
6. the high frequency plasma heater according to claim 1 for high-temperature metal powder nodularization, it is characterised in that：Institute
The ratio between the horizontal sectional area of nozzle (9) inside opening and horizontal sectional area of electric discharge confinement tube (2) is stated to be not less than
7. the high frequency plasma heater according to claim 1 for high-temperature metal powder nodularization, it is characterised in that：In
The lower surface of motive confinement tube (3) is concordant with the upper surface of the circle of induction coil (1) first；The following table of high pressure water cooling discharge tube (7)
Face is located between the circle of induction coil (1) first and the 3rd circle.
8. the high frequency plasma heater according to claim 1 for high-temperature metal powder nodularization, it is characterised in that：Institute
State horizontal level in the middle part of center rotation gas part (5) and be provided with central gas air intake duct；Horizontal level is provided with the middle part of outer shroud rotation gas part (4)
Outer shroud gas air intake duct；The outer wall of electric discharge confinement tube (2) is provided with cooling-water duct.
9. the high frequency plasma heater according to claim 8 for high-temperature metal powder nodularization, it is characterised in that：Add
The dielectric gas of hot device includes outer shroud gas, central gas and carrier gas；Wherein, outer shroud gas is entered by the outer shroud gas of outer shroud rotation gas part (4)
Air flue enters heater；The central gas air intake duct that central gas revolves gas part (5) by center enters heater；Carrier gas and high-temperature metal
Powder enters heater by high pressure water cooling discharge tube (7).
10. the high frequency plasma heater according to claim 9 for high-temperature metal powder nodularization, it is characterised in that：
The carrier gas is argon gas.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201720672040.XU CN206966635U (en) | 2017-06-09 | 2017-06-09 | High frequency plasma heater for high-temperature metal powder nodularization |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201720672040.XU CN206966635U (en) | 2017-06-09 | 2017-06-09 | High frequency plasma heater for high-temperature metal powder nodularization |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN206966635U true CN206966635U (en) | 2018-02-06 |
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ID=61408022
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201720672040.XU Active CN206966635U (en) | 2017-06-09 | 2017-06-09 | High frequency plasma heater for high-temperature metal powder nodularization |
Country Status (1)
| Country | Link |
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| CN (1) | CN206966635U (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107186209A (en) * | 2017-06-09 | 2017-09-22 | 中国航天空气动力技术研究院 | High frequency plasma heater for high-temperature metal powder nodularization |
-
2017
- 2017-06-09 CN CN201720672040.XU patent/CN206966635U/en active Active
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107186209A (en) * | 2017-06-09 | 2017-09-22 | 中国航天空气动力技术研究院 | High frequency plasma heater for high-temperature metal powder nodularization |
| CN107186209B (en) * | 2017-06-09 | 2022-03-22 | 云航时代(重庆)科技有限公司 | High-frequency plasma heater for spheroidizing high-temperature metal powder |
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| TR01 | Transfer of patent right |
Effective date of registration: 20210427 Address after: 618 Liangjiang Avenue, Yubei District, Chongqing Patentee after: Yunhang times (Chongqing) Technology Co.,Ltd. Address before: 17 Yungang West Road, Fengtai District, Beijing 100074 Patentee before: CHINA ACADEMY OF AEROSPACE AERODYNAMICS |