CN114101669A - Current-assisted molding and sintering integrated continuous production system and production method - Google Patents
Current-assisted molding and sintering integrated continuous production system and production method Download PDFInfo
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- CN114101669A CN114101669A CN202111416720.2A CN202111416720A CN114101669A CN 114101669 A CN114101669 A CN 114101669A CN 202111416720 A CN202111416720 A CN 202111416720A CN 114101669 A CN114101669 A CN 114101669A
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F3/00—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces
- B22F3/003—Apparatus, e.g. furnaces
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F3/00—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces
- B22F3/004—Filling molds with powder
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F3/00—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces
- B22F3/005—Loading or unloading powder metal objects
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F3/00—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces
- B22F3/02—Compacting only
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F3/00—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces
- B22F3/02—Compacting only
- B22F3/03—Press-moulding apparatus therefor
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F3/00—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces
- B22F3/12—Both compacting and sintering
- B22F3/14—Both compacting and sintering simultaneously
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
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- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
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Abstract
The invention belongs to the technical field of powder metallurgy, and relates to a continuous production system integrating current auxiliary forming and sintering and a production method, wherein an upper electrode and a lower electrode of the production system are symmetrically arranged on a transmission unit, a transmission platform is arranged at the lower end of the transmission unit, and a power supply unit is respectively connected with the upper electrode and the lower electrode; the mould is fixed on the conveying platform, a through hole forming cavity is arranged on the mould, the forming cavity is positioned between the upper electrode and the lower electrode, and an insulating layer is arranged on the inner wall of the forming cavity; the auxiliary unit is arranged at one side of the conveying platform. The invention organically combines the electric field auxiliary sintering technology with the traditional powder metallurgy production system, overcomes the problems of long flow, high energy consumption, high pollution, low efficiency, low product precision, poor performance, difficulty in realizing large-scale continuous production by the electric field auxiliary sintering technology, high production cost and the like in the traditional powder metallurgy part production system, and is suitable for large-scale continuous production of various metal-based powder metallurgy parts.
Description
Technical Field
The invention belongs to the technical field of powder metallurgy, and particularly relates to a current-assisted molding and sintering integrated continuous production system and a production method suitable for molding powder metallurgy parts.
Technical Field
The traditional powder metallurgy part production system mainly comprises the processes of powder preparation, press forming, sintering and the like, and the energy consumption of the sintering process is the largest. The sintering method adopted by various large powder metallurgy enterprises at home and abroad at present and the sintering method of pottery sintering thousands of years ago have no essential difference. The external field assisted sintering technology appears in the last 100 years, and the traditional sintering time of hours can be shortened to minutes or even seconds. Among them, the most widely studied and applied technology is the electric field assisted sintering technology, such as the discharge plasma sintering (SPS) technology, which is currently commercialized successfully, but its application is mainly limited to laboratory sample preparation, and the SPS is rarely reported in industrial application, mainly because the SPS relies on complex and precise equipment modules, such as a temperature control module, a pressure control module, etc., and its expensive equipment cost and technical characteristics of non-continuous production limit the industrial application of SPS.
The forming and sintering processes are separated in conventional powder metallurgy production systems. After the powder raw materials are continuously molded in the pressure device to obtain a large number of green bodies of parts, the green bodies are uniformly put into a furnace for long-time sintering, so that the problems of long flow, high energy consumption, high pollution, low efficiency, low product precision, poor performance and the like of the traditional powder metallurgy production process are caused. The electric field assisted sintering technology can shorten the time for preparing a single product, remarkably improve the product performance, but is difficult to realize large-scale sample preparation as the traditional powder metallurgy part production system.
Therefore, a continuous production system which organically combines an electric field auxiliary sintering technology with a traditional powder metallurgy production system and integrates an integrated type and a sintering process is needed to be designed, the technical advantages of electric field auxiliary sintering can be fully exerted while large-scale modification on the traditional powder metallurgy production system is avoided, the problems of long flow, high energy consumption, high pollution, low efficiency, low product precision, poor performance and the like in the traditional powder metallurgy part production system are solved, and large-scale and high-throughput production of high-performance powder metallurgy parts is realized.
The prior art is commonly used for external field assisted sintering, and the common characteristic of the prior art is that the sample sintering is realized by using joule heat generated by current flowing through a powder green body or a die, and the prior art has the problem that large-scale continuous production is difficult to realize and the prior art can only be used for preparing a single laboratory sample.
Disclosure of Invention
The invention aims to design a continuous production system integrating current-assisted molding and sintering of powder metallurgy parts, aiming at the defects of the prior art and solving the problems of long flow, high energy consumption, high pollution, low efficiency, low product precision, poor performance, incapability of realizing large-scale continuous production, high production cost and the like in the traditional powder metallurgy part production system.
The technical scheme of the invention is as follows: a continuous production system integrating current-assisted molding and sintering of powder metallurgy parts comprises: the device comprises an upper electrode, a lower electrode, a die, a hopper, a conveying platform, a power supply unit, a transmission unit, an insulating layer and a through hole forming cavity; the upper electrode and the lower electrode are connected with a power supply 8 and a transmission unit; the die is insulated from the upper electrode 1 and the lower electrode through an insulating layer on the inner wall of the through hole forming cavity, and is nested and fixed on the conveying platform; the hopper is internally provided with powder raw materials, and the powder raw materials are controlled by the mechanical arm and are injected into the die in the continuous forming process. The implementation steps of the continuous production system integrating the current auxiliary forming and sintering of the powder metallurgy parts comprise:
(1) the hopper injects powder raw materials for the mould.
(2) The transmission unit drives the upper power supply electrode to move, and powder green bodies are pressed. In the process, the upper electrode, the lower electrode, the powder green compact and the power supply unit form a closed loop; then, the power supply unit is opened, current passes through the powder green compact, and the current-assisted molding and sintering integrated process is carried out, wherein the pre-pressing pressure is kept in the process.
(3) After the current-assisted forming and sintering integrated process is completed, the power supply is turned off, and the transmission unit drives the upper electrode and the lower electrode to move upwards to demould the sintered body.
(4) The transmission platform transports the sintered body away, and the transmission unit drives the lower electrode to reset.
(5) And (4) repeating the steps (1) to (4) to realize the continuous production of the powder metallurgy part integrating current auxiliary forming and sintering.
Further, the upper and lower electrode materials include tungsten carbide cobalt cemented carbide, tungsten based alloy, nickel based superalloy, for connecting the powder green compact into the circuit of the power supply unit and injecting electrical energy and pressure into the powder green compact during pressing.
Further, the outer layer material of the die comprises tungsten carbide cobalt hard alloy, tungsten-based alloy and nickel-based high-temperature alloy, and the inner insulating layer material comprises silicon nitride, silicon carbide, aluminum nitride and zirconium oxide.
Further, the hopper is controlled by a mechanical arm and is used for feeding the die 3 after the lower electrode 2 is reset.
Further, the conveying platform is used for conveying the sintered body after demolding.
Further, the power supply unit includes a dc power supply, an ac power supply, or a pulsed dc power supply.
Further, the transmission unit comprises a servo electric cylinder and a hydraulic transmission unit. The transmission unit 9 drives the upper electrode and the lower electrode to provide power for continuous molding, sintering and demolding of the powder green body and the sintered body.
Further, the production system is used for large-scale continuous production of various metal-based powder metallurgy parts, including metal-based powder metallurgy parts such as aluminum base, copper base, titanium base, iron base, hard alloy and the like.
Further, the atmosphere of the molding and sintering integrated process of the production system is optional and comprises air, vacuum and inert gas.
The invention has the beneficial effects that: by adopting the production system, the upper electrode, the lower electrode, the die with the forming hole and the conveying platform are matched with each other, the powder is pre-pressed and then pressed under the assistance of current, so that the integration of the forming and sintering processes in the traditional powder metallurgy production system can be realized, the electric field assisted sintering technology is successfully and organically combined with the traditional powder metallurgy production system, and the production system has the capability of large-scale continuous production. After the powder green body is subjected to current-assisted pressing, the density is improved by 20-40% compared with that of a pre-pressed green body. In addition, due to the combination of the special die and the electrode, in the current-assisted pressing process, the powder blank is in a low-oxygen partial pressure environment, the forming and sintering integrated process can be carried out in the air under most conditions, atmosphere protection is not needed, the production efficiency can be further improved, and the production cost is reduced. Therefore, the invention can fully play the technical advantages of electric field auxiliary sintering while avoiding large-scale modification of the traditional powder metallurgy production system, reduce the cost of the electric field auxiliary sintering, and overcome the problems of long flow, high energy consumption, high pollution, low efficiency, low product precision, poor performance, difficulty in realizing large-scale continuous production by the electric field auxiliary sintering technology, high production cost and the like in the traditional powder metallurgy part production system.
Drawings
FIG. 1 is a schematic structural diagram of a current-assisted molding and sintering integrated continuous production system of the present invention.
Fig. 2 is a schematic sectional view of a mold used in the production system of the present invention.
In the figure:
1. the device comprises an upper electrode, a lower electrode 2, a die 3, a hopper 4, a conveying platform 5, a powder green body 6, a sintered body 7, a power supply unit 8, a transmission unit 9, an insulating layer 10 and a through hole forming cavity 11; wherein a, b, c and d respectively correspond to four main steps of charging, current-assisted forming and sintering, demoulding, sintered body conveying, electrode resetting, recharging and the like.
Detailed Description
The technical solution of the present invention is further explained with reference to the drawings and the embodiments.
As shown in fig. 1-2, the present invention relates to a continuous production system for current-assisted molding and sintering of powder metallurgy parts, which comprises: the device comprises an upper electrode 1, a lower electrode 2, a mould 3, a conveying platform 5, a transmission unit 9, an auxiliary unit and a power supply unit 8;
the upper electrode 1 and the lower electrode 2 are symmetrically arranged on the transmission unit 9, the conveying platform 5 is arranged at the lower end of the transmission unit 9, and the power supply unit 8 is respectively connected with the upper electrode 1 and the lower electrode 2;
the die 3 is fixed on the conveying platform 5, a through hole forming cavity 11 is arranged on the die 3, the through hole forming cavity 11 is positioned between the upper electrode 1 and the lower electrode 2, and an insulating layer 10 is arranged on the inner wall of the through hole forming cavity 11;
the auxiliary unit is arranged at one side of the transfer platform 5.
The diameter of the through hole forming cavity is 1-1.2 times of the diameter of the upper electrode and the lower electrode, and the cross section of the through hole forming cavity 11 is the same as that of the upper electrode 1 and the lower electrode 2.
The power supply unit 8 is a direct current power supply, an alternating current power supply or a pulse direct current power supply.
The upper electrode 1, the lower electrode 2 and the die 3 are made of high-temperature-resistant high-strength alloy;
the insulating layer 10 is one of silicon nitride, silicon carbide, aluminum nitride, or zirconia.
The high-temperature-resistant high-strength alloy is tungsten carbide cobalt hard alloy, tungsten-based alloy or nickel-based high-temperature alloy.
The invention also provides a production method adopting the continuous production system, which specifically comprises the following steps:
s1) starting the auxiliary device to inject the powder raw material into the through hole forming cavity of the die through the hopper;
s2) starting the transmission unit to drive the upper electrode and the lower electrode to move, inserting the upper electrode and the lower electrode into the through hole forming cavity, and pre-pressing the powder raw material to obtain a powder green body;
s3), starting a power supply unit, and carrying out further current-assisted press forming and sintering on the powder green compact by a current through an upper electrode and a lower electrode, wherein the pre-pressing pressure is kept in the process;
s4) after the current-assisted forming and sintering integrated process is finished, turning off a power supply, and driving an upper electrode and a lower electrode to move upwards through a transmission unit to demould the obtained sintered body;
s5) starting the conveying platform to convey the demolded sintered body away, driving the lower electrode to reset through the transmission unit, and repeating S1) -S4) to realize continuous production of the powder metallurgy parts.
The raw material powder of S1) is aluminum-based, copper-based, titanium-based, iron-based, hard alloy or other metal-based powder.
The pre-pressing pressure of S2) is as follows: 100-
The process parameters of current-assisted molding and sintering of S3): the current is 100-10000A, the voltage is 3-50V, the frequency is 1-50kHz, and the sintering time is 5-600 s.
A powder metallurgy part is prepared by the production method.
Example 1:
a continuous production system integrating current-assisted molding and sintering of powder metallurgy parts comprises: the device comprises an upper electrode 1, a lower electrode 2, a die 3, a hopper 4, a conveying platform 5, a powder green body 6, a sintered body 7, a power supply 8, a transmission unit 9, an insulating layer 10 and a through hole forming cavity 11; the upper electrode 1 and the lower electrode 2 are connected with a power supply 8 and a transmission unit 9; the die 3 is insulated from the upper electrode 1 and the lower electrode 2 through an insulating layer 10 on the inner wall of the through hole forming cavity 11, and is nested and fixed on the conveying platform 5; the hopper 4 is internally provided with powder raw materials, and is controlled by a mechanical arm and used for injecting the powder raw materials into the die in the continuous forming process.
The implementation steps of the continuous production system integrating the current auxiliary forming and sintering of the powder metallurgy parts comprise:
(1) the hopper 4 injects the powder raw material into the through-hole forming cavity 11 of the die 3 (this step corresponds to a in fig. 1).
(2) The transmission unit 9 drives the upper electrode 1 to move, the powder green bodies 6 are pressed, and the pressures of the upper electrode and the lower electrode are equal. In the process, the upper electrode 1, the lower electrode 2, the powder green compact 6 and the power supply 8 form a closed loop; then, the power supply 8 is turned on, and current is passed through the green powder compact 6, and a current-assisted molding and sintering integrated process (this step corresponds to b in fig. 1) is performed, in which the pre-pressing pressure is maintained.
(3) After the current-assisted forming and sintering integrated process is completed, the power supply is turned off, and the transmission unit 9 drives the upper electrode 1 and the lower electrode 2 to move upwards to demould the sintered body 7 (this step corresponds to c in fig. 1).
(4) The conveying platform 5 transports the sintered body 7 away, and the transmission unit 9 drives the lower electrode 2 to reset (this step corresponds to d in fig. 1).
(5) And (4) repeating the steps (1) to (4) to realize the continuous production of the powder metallurgy part integrating current auxiliary forming and sintering.
Further, the outer layer materials of the upper electrode 1, the lower electrode 2 and the die 3 comprise tungsten carbide cobalt hard alloy, tungsten-based alloy and nickel-based high-temperature alloy, wherein the electrodes are used for connecting the powder green body 6 to a circuit of a power supply 8 and injecting electric energy and pressure into the powder green body 6 in the pressing process.
Further, the material of the insulating layer inside the mold comprises silicon nitride, silicon carbide, aluminum nitride and zirconium oxide.
Further, the hopper 4 is controlled by a mechanical arm for feeding the mold 3 after the lower electrode 2 is reset.
Further, the conveying platform 5 is used for conveying the sintered body 7 after demoulding.
Further, the power supply 8 includes a dc power supply, an ac power supply, and a pulsed dc power supply.
Further, the transmission unit 9 includes a servo electric cylinder, a hydraulic transmission unit. The transmission unit 9 drives the upper electrode 1 and the lower electrode 2 to provide power for continuous forming, sintering and demoulding of the powder green body 6 and the sintered body 7.
Further, the production system is used for large-scale continuous production of various metal-based powder metallurgy parts, including metal-based powder metallurgy parts such as aluminum base, copper base, titanium base, iron base, hard alloy and the like.
Further, the atmosphere of the molding and sintering integrated process of the production system is optional and comprises air, vacuum and inert gas.
The invention can also place the multiple groups of electrodes and the die according to an array and connect with one or more power supplies and transmission units in parallel, thereby realizing the purpose of high-flux preparation.
Example 2:
the invention is suitable for the continuous production of high-performance powder metallurgy parts made of various materials, in the embodiment, an aluminum-based metal material, namely Al-12Si alloy is used as a model material, Al-12Si cylindrical parts with the diameter of 10mm are continuously produced, and the forming and sintering integrated process is carried out in the air. The hopper 4 is used for injecting Al-12Si alloy powder raw materials into the die 3; the transmission unit 9 drives the upper electrode 1 to move, and the powder green bodies 6 are pressed, wherein the pressing pressure is 100 MPa. In the process, the upper electrode 1, the lower electrode 2, the powder green compact 6 and the pulse direct-current power supply 8 form a closed loop; then, the pulse dc power supply 8 is turned on, and the power supply output parameters are set as follows: the current is 1500A, the voltage is 3V, the frequency is 31kHz, the current passes through the powder green compact 6, and the current auxiliary forming and sintering integrated process lasts for 10 s; after the current-assisted forming and sintering integrated process is finished, the power supply is turned off, the transmission unit 9 drives the upper electrode 1 and the lower electrode 2 to move upwards, and the Al-12Si powder metallurgy part 7 is demoulded; the conveying platform 5 transports the Al-12Si powder metallurgy part 7 away, the transmission unit 9 drives the lower electrode 2 to reset, and the lower electrode is cooled for 30 s; by repeating the steps, the continuous production of the Al-12Si powder metallurgy parts with the average density of 99.6 percent can be carried out.
Example 3:
the invention is suitable for continuous production of high-performance powder metallurgy parts made of various materials, in the embodiment, a titanium-based metal material, namely Ti-6Al-4V alloy is used as a model material, Ti-6Al-4V gear parts with addendum circle diameter of 10.5mm and tooth number of 15 are continuously produced, and the forming and sintering integrated process is carried out in the inert atmosphere of argon. The hopper 4 is used for injecting Ti-6Al-4V alloy powder raw materials into the die 3; the transmission unit 9 drives the upper electrode 1 to move, and the powder green bodies 6 are pressed, wherein the pressing pressure is 600 MPa. In the process, the upper electrode 1, the lower electrode 2, the powder green compact 6 and the pulse direct-current power supply 8 form a closed loop; then, the pulse dc power supply 8 is turned on, and the power supply output parameters are set as follows: the current is 600A, the voltage is 10V, the frequency is 50kHz, the current passes through the powder green compact 6, and the current auxiliary forming and sintering integrated process lasts for 60 s; after the current-assisted forming and sintering integrated process is finished, the power supply is turned off, the transmission unit 9 drives the upper electrode 1 and the lower electrode 2 to move upwards, and the Ti-6Al-4V powder metallurgy parts 7 are demoulded; the conveying platform 5 transports the Ti-6Al-4V powder metallurgy parts 7 away, the transmission unit 9 drives the lower electrode 2 to reset, and the lower electrode is cooled for 65 s; the above steps are repeated, and the continuous production of Ti-6Al-4V powder metallurgy parts with the average density of 98.1 percent can be carried out.
Example 4:
the invention is suitable for continuous production of high-performance powder metallurgy parts made of various materials, in the embodiment, a hard alloy, namely WC-10% Co is used as a model material, cylindrical parts with the diameter of 25mm are continuously produced, and the forming and sintering integrated process is carried out in vacuum. The hopper 4 is used for injecting WC-10% Co alloy powder raw materials into the die 3; the transmission unit 9 drives the upper electrode 1 to move, and the powder green bodies 6 are pressed, wherein the pressing pressure is 1000 MPa. In the process, the upper electrode 1, the lower electrode 2, the powder green compact 6 and the alternating current power supply 8 form a closed loop; then, the ac power supply 8 is turned on, and the power supply output parameters are set as follows: the current is 5000A, the voltage is 20V, the frequency is 1kHz, the current passes through the powder green compact 6, and the integrated process of current auxiliary forming and sintering is carried out for 180 s; after the current-assisted forming and sintering integrated process is finished, the power supply is turned off, the transmission unit 9 drives the upper electrode 1 and the lower electrode 2 to move upwards, and the WC-10% Co powder metallurgy parts 7 are demoulded; the conveying platform 5 transports the WC-10% Co powder metallurgy parts 7 away, the transmission unit 9 drives the lower electrode 2 to reset, and the lower electrode is cooled for 50 s; the steps are repeated, so that the continuous production of WC-10% Co powder metallurgy parts with the average density of 99.4% can be carried out.
Example 5:
the invention is suitable for continuous production of high-performance powder metallurgy parts made of various materials, in the embodiment, an iron-based metal material, namely a titanium carbide reinforced high-speed steel composite material (the content of titanium carbide is 40 wt.%) is used as a model material, cylindrical parts with the diameter of 6mm are continuously produced, and the forming and sintering integrated process is carried out in air. The hopper 4 is a raw material of titanium carbide reinforced high-speed steel composite powder injected into the die 3; the transmission unit 9 drives the upper electrode 1 to move, and the powder green bodies 6 are pressed, wherein the pressing pressure is 1500 MPa. In the process, the upper electrode 1, the lower electrode 2, the powder green compact 6 and the direct current power supply 8 form a closed loop; then, the dc power supply 8 is turned on, and the power supply output parameters are set as follows: the current 275A, the voltage 50V and the current pass through the powder green compact 6 to carry out the integrated process of current-assisted molding and sintering for 420 s; after the integrated process of current-assisted forming and sintering is completed, the power supply is turned off, the transmission unit 9 drives the upper electrode 1 and the lower electrode 2 to move upwards, and the titanium carbide reinforced high-speed steel composite material powder metallurgy part 7 is demoulded; the conveying platform 5 transports the titanium carbide reinforced high-speed steel composite material powder metallurgy parts 7 away, the transmission unit 9 drives the lower electrode 2 to reset, and the parts are cooled for 50 s; by repeating the steps, the continuous production of the titanium carbide reinforced high-speed steel composite material powder metallurgy parts with the average density of 99.7 percent can be carried out.
Example 6:
the invention is suitable for the continuous production of high-performance powder metallurgy parts made of various materials, in the embodiment, a copper-based powder metallurgy friction material is used as a model material, the main alloy elements of the copper-based powder metallurgy friction material are tin, zinc, iron, nickel, phosphorus and the like, the cylindrical parts with the diameter of 35mm are continuously produced, and the forming and sintering integrated process is carried out in the air. The hopper 4 is used for injecting a copper-based powder metallurgy friction material powder raw material into the die 3; the transmission unit 9 drives the upper electrode 1 to move, and the powder green bodies 6 are pressed, wherein the pressing pressure is 760 MPa. In the process, the upper electrode 1, the lower electrode 2, the powder green compact 6 and the pulse direct-current power supply 8 form a closed loop; then, the pulse dc power supply 8 is turned on, and the power supply output parameters are set as follows: 8600A of current, 3.7V of voltage and 20kHz of frequency, wherein the current passes through the powder green compact 6 to carry out the integrated process of current-assisted molding and sintering for 300 s; after the integrated process of current-assisted forming and sintering is completed, the power supply is turned off, the transmission unit 9 drives the upper electrode 1 and the lower electrode 2 to move upwards, and the copper-based powder metallurgy friction material part 7 is demoulded; the conveying platform 5 transports the copper-based powder metallurgy friction material part 7 away, the transmission unit 9 drives the lower electrode 2 to reset, and the copper-based powder metallurgy friction material part is cooled for 64 s; the steps are repeated, and the continuous production of the copper-based powder metallurgy friction material part with the average density of 99.5 percent can be carried out.
The continuous production system and the production method integrating current-assisted molding and sintering provided by the embodiment of the application are described in detail above. The above description of the embodiments is only for the purpose of helping to understand the method of the present application and its core ideas; meanwhile, for a person skilled in the art, according to the idea of the present application, there may be variations in the specific embodiments and the application scope, and in summary, the content of the present specification should not be construed as a limitation to the present application.
As used in the specification and claims, certain terms are used to refer to particular components. As one skilled in the art will appreciate, manufacturers may refer to a component by different names. This specification and claims do not intend to distinguish between components that differ in name but not function. In the following description and in the claims, the terms "include" and "comprise" are used in an open-ended fashion, and thus should be interpreted to mean "include, but not limited to. "substantially" means within an acceptable error range, and a person skilled in the art can solve the technical problem within a certain error range to substantially achieve the technical effect. The description which follows is a preferred embodiment of the present application, but is made for the purpose of illustrating the general principles of the application and not for the purpose of limiting the scope of the application. The protection scope of the present application shall be subject to the definitions of the appended claims.
It is also noted that the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a good or system that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such good or system. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other like elements in a commodity or system that includes the element.
It should be understood that the term "and/or" as used herein is merely one type of association that describes an associated object, meaning that three relationships may exist, e.g., a and/or B may mean: a exists alone, A and B exist simultaneously, and B exists alone. In addition, the character "/" herein generally indicates that the former and latter related objects are in an "or" relationship.
The foregoing description shows and describes several preferred embodiments of the present application, but as aforementioned, it is to be understood that the application is not limited to the forms disclosed herein, but is not to be construed as excluding other embodiments and is capable of use in various other combinations, modifications, and environments and is capable of changes within the scope of the application as described herein, commensurate with the above teachings, or the skill or knowledge of the relevant art. And that modifications and variations may be effected by those skilled in the art without departing from the spirit and scope of the application, which is to be protected by the claims appended hereto.
Claims (10)
1. A continuous production system integrating current-assisted molding and sintering, which is characterized by comprising: the device comprises an upper electrode, a lower electrode, a die, a conveying platform, a transmission unit, an auxiliary unit and a power supply unit;
the upper electrode and the lower electrode are symmetrically arranged on the transmission unit, the conveying platform is arranged at the lower end of the transmission unit, and the power supply unit is respectively connected with the upper electrode and the lower electrode;
the die is fixed on the conveying platform, a through hole forming cavity is arranged on the die and is positioned between the upper electrode and the lower electrode, and an insulating layer is arranged on the inner wall of the through hole forming cavity;
the auxiliary unit is disposed at one side of the transfer platform.
2. The continuous production system according to claim 1, wherein the diameter of the through-hole forming cavity is 1 to 1.2 times the diameter of the upper electrode and the lower electrode.
3. The continuous production system of claim 1, wherein the power supply unit is a dc power supply, an ac power supply, or a pulsed dc power supply.
4. The continuous production system of claim 1, wherein the upper electrode, the lower electrode and the mold material are all high temperature and high strength alloys;
the insulating layer is one of silicon nitride, silicon carbide, aluminum nitride or zirconium oxide.
5. The continuous production system of claim 4, wherein the high temperature and high strength alloy is tungsten carbide cobalt cemented carbide, tungsten based alloy or nickel based superalloy.
6. A production method using the continuous production system according to any one of claims 1 to 5, characterized in that the production method specifically comprises the steps of:
s1) starting the auxiliary device to inject the raw material powder into the through hole forming cavity of the die through the hopper;
s2) starting the transmission unit to drive the upper electrode and the lower electrode to move, inserting the upper electrode and the lower electrode into the through hole forming cavity, and pre-pressing the powder raw material to obtain a powder green body;
s3), starting a power supply unit, and carrying out further current-assisted press forming and sintering on the powder green compact by using a current through an upper electrode and a lower electrode;
s4) after the current-assisted forming and sintering integrated process is finished, turning off a power supply, and driving an upper electrode and a lower electrode to move upwards through a transmission unit to demould the obtained sintered body;
s5) starting the conveying platform to convey the demolded sintered body away, driving the lower electrode to reset through the transmission unit, and repeating S1) -S4) to realize continuous production of the powder metallurgy parts.
7. The production method according to claim 6, wherein the raw material powder of S1) is an aluminum-based, copper-based, titanium-based, iron-based, or cemented carbide powder.
8. The production method as claimed in claim 6, wherein the prepressing pressure of S2) is: 100-1500 MPa.
9. The production method as claimed in claim 6, wherein the process parameters of the current-assisted forming and sintering of S3): the current is 100-10000A, the voltage is 3-50V, the frequency is 1-50kHz, and the sintering time is 5-600 s.
10. A powder metallurgical component, characterized in that it is produced by a production method according to any one of claims 6 to 9.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115351274A (en) * | 2022-09-09 | 2022-11-18 | 金堆城钼业股份有限公司 | Pressing and sintering integrated forming device and forming method for dispersed particle powder metallurgy |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1969347A (en) * | 2004-07-01 | 2007-05-23 | 因太金属株式会社 | Production method for magnetic-anisotropy rare-earth sintered magnet and production device therefor |
| CN107321987A (en) * | 2017-07-21 | 2017-11-07 | 四川大学 | Multiple physical field couples superfast sintering integrated equipment |
| CN108326297A (en) * | 2018-04-24 | 2018-07-27 | 中南大学 | A kind of building mortion of large-size ultra-thin powder metallurgy functionally gradient material (FGM) and application |
| CN109894615A (en) * | 2019-04-19 | 2019-06-18 | 扬州海昌新材股份有限公司 | Pulsed discharge flash sintering metal base components near-net-shape process |
| CN112410600A (en) * | 2020-10-30 | 2021-02-26 | 北京科技大学 | Flash sintering preparation method of uranium-zirconium hydride and uranium-yttrium hydride fuel pellets |
-
2021
- 2021-11-25 CN CN202111416720.2A patent/CN114101669B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1969347A (en) * | 2004-07-01 | 2007-05-23 | 因太金属株式会社 | Production method for magnetic-anisotropy rare-earth sintered magnet and production device therefor |
| CN107321987A (en) * | 2017-07-21 | 2017-11-07 | 四川大学 | Multiple physical field couples superfast sintering integrated equipment |
| CN108326297A (en) * | 2018-04-24 | 2018-07-27 | 中南大学 | A kind of building mortion of large-size ultra-thin powder metallurgy functionally gradient material (FGM) and application |
| CN109894615A (en) * | 2019-04-19 | 2019-06-18 | 扬州海昌新材股份有限公司 | Pulsed discharge flash sintering metal base components near-net-shape process |
| CN112410600A (en) * | 2020-10-30 | 2021-02-26 | 北京科技大学 | Flash sintering preparation method of uranium-zirconium hydride and uranium-yttrium hydride fuel pellets |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115351274A (en) * | 2022-09-09 | 2022-11-18 | 金堆城钼业股份有限公司 | Pressing and sintering integrated forming device and forming method for dispersed particle powder metallurgy |
| CN115351274B (en) * | 2022-09-09 | 2024-01-19 | 金堆城钼业股份有限公司 | Pressing and sintering integrated forming device and forming method for dispersion particle powder metallurgy |
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