CN107096919A - The equipment for sintering the method for conductive powder and performing methods described - Google Patents
The equipment for sintering the method for conductive powder and performing methods described Download PDFInfo
- Publication number
- CN107096919A CN107096919A CN201710089756.1A CN201710089756A CN107096919A CN 107096919 A CN107096919 A CN 107096919A CN 201710089756 A CN201710089756 A CN 201710089756A CN 107096919 A CN107096919 A CN 107096919A
- Authority
- CN
- China
- Prior art keywords
- sintering
- current density
- voltage
- activation
- powder
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 238000005245 sintering Methods 0.000 title claims abstract description 118
- 239000000843 powder Substances 0.000 title claims abstract description 78
- 238000000034 method Methods 0.000 title claims abstract description 41
- 230000004913 activation Effects 0.000 claims abstract description 90
- 238000009413 insulation Methods 0.000 claims abstract description 7
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical group [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 claims description 3
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical group [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims description 3
- 239000004411 aluminium Substances 0.000 claims description 2
- 229910052782 aluminium Inorganic materials 0.000 claims description 2
- 230000002045 lasting effect Effects 0.000 claims 6
- 239000000203 mixture Substances 0.000 claims 1
- 230000009466 transformation Effects 0.000 claims 1
- 239000002245 particle Substances 0.000 description 9
- 230000008569 process Effects 0.000 description 9
- 238000000280 densification Methods 0.000 description 8
- 238000005516 engineering process Methods 0.000 description 7
- 238000004519 manufacturing process Methods 0.000 description 7
- 230000008859 change Effects 0.000 description 5
- 238000002490 spark plasma sintering Methods 0.000 description 5
- 238000007088 Archimedes method Methods 0.000 description 4
- 239000000463 material Substances 0.000 description 4
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- 229910009043 WC-Co Inorganic materials 0.000 description 2
- 239000003990 capacitor Substances 0.000 description 2
- 238000007596 consolidation process Methods 0.000 description 2
- 230000009849 deactivation Effects 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 238000009826 distribution Methods 0.000 description 2
- 238000009706 electric current assisted sintering Methods 0.000 description 2
- 230000005611 electricity Effects 0.000 description 2
- 230000001788 irregular Effects 0.000 description 2
- 238000009707 resistance sintering Methods 0.000 description 2
- 239000010936 titanium Substances 0.000 description 2
- 229910052719 titanium Inorganic materials 0.000 description 2
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 239000011248 coating agent Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 239000010949 copper Substances 0.000 description 1
- 229910052802 copper Inorganic materials 0.000 description 1
- 238000005520 cutting process Methods 0.000 description 1
- 230000006378 damage Effects 0.000 description 1
- 230000005684 electric field Effects 0.000 description 1
- 230000007717 exclusion Effects 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 238000005457 optimization Methods 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 238000003825 pressing Methods 0.000 description 1
- 230000001681 protective effect Effects 0.000 description 1
- 238000011946 reduction process Methods 0.000 description 1
- 238000010301 surface-oxidation reaction Methods 0.000 description 1
Classifications
-
- 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
- B22F3/10—Sintering only
- B22F3/105—Sintering only by using electric current other than for infrared radiant energy, laser radiation or plasma ; by ultrasonic bonding
-
- 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
-
- 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
- B22F3/087—Compacting only using high energy impulses, e.g. magnetic field impulses
-
- 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
-
- 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
- B22F3/10—Sintering only
- B22F3/105—Sintering only by using electric current other than for infrared radiant energy, laser radiation or plasma ; by ultrasonic bonding
- B22F2003/1051—Sintering only by using electric current other than for infrared radiant energy, laser radiation or plasma ; by ultrasonic bonding by electric discharge
-
- 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
- B22F2201/00—Treatment under specific atmosphere
- B22F2201/50—Treatment under specific atmosphere air
-
- 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
- B22F2202/00—Treatment under specific physical conditions
- B22F2202/06—Use of electric fields
-
- 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
- B22F2301/00—Metallic composition of the powder or its coating
- B22F2301/15—Nickel or cobalt
-
- 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
- B22F2301/00—Metallic composition of the powder or its coating
- B22F2301/20—Refractory metals
- B22F2301/205—Titanium, zirconium or hafnium
-
- 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
- B22F2301/00—Metallic composition of the powder or its coating
- B22F2301/40—Intermetallics other than rare earth-Co or -Ni or -Fe intermetallic alloys
-
- 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
- B22F2998/00—Supplementary information concerning processes or compositions relating to powder metallurgy
- B22F2998/10—Processes characterised by the sequence of their steps
-
- 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
- B22F3/16—Both compacting and sintering in successive or repeated steps
- B22F3/164—Partial deformation or calibration
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C14/00—Alloys based on titanium
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C21/00—Alloys based on aluminium
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C29/00—Alloys based on carbides, oxides, nitrides, borides, or silicides, e.g. cermets, or other metal compounds, e.g. oxynitrides, sulfides
- C22C29/02—Alloys based on carbides, oxides, nitrides, borides, or silicides, e.g. cermets, or other metal compounds, e.g. oxynitrides, sulfides based on carbides or carbonitrides
- C22C29/06—Alloys based on carbides, oxides, nitrides, borides, or silicides, e.g. cermets, or other metal compounds, e.g. oxynitrides, sulfides based on carbides or carbonitrides based on carbides, but not containing other metal compounds
- C22C29/08—Alloys based on carbides, oxides, nitrides, borides, or silicides, e.g. cermets, or other metal compounds, e.g. oxynitrides, sulfides based on carbides or carbonitrides based on carbides, but not containing other metal compounds based on tungsten carbide
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C29/00—Alloys based on carbides, oxides, nitrides, borides, or silicides, e.g. cermets, or other metal compounds, e.g. oxynitrides, sulfides
- C22C29/02—Alloys based on carbides, oxides, nitrides, borides, or silicides, e.g. cermets, or other metal compounds, e.g. oxynitrides, sulfides based on carbides or carbonitrides
- C22C29/06—Alloys based on carbides, oxides, nitrides, borides, or silicides, e.g. cermets, or other metal compounds, e.g. oxynitrides, sulfides based on carbides or carbonitrides based on carbides, but not containing other metal compounds
- C22C29/10—Alloys based on carbides, oxides, nitrides, borides, or silicides, e.g. cermets, or other metal compounds, e.g. oxynitrides, sulfides based on carbides or carbonitrides based on carbides, but not containing other metal compounds based on titanium carbide
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C32/00—Non-ferrous alloys containing at least 5% by weight but less than 50% by weight of oxides, carbides, borides, nitrides, silicides or other metal compounds, e.g. oxynitrides, sulfides, whether added as such or formed in situ
- C22C32/0047—Non-ferrous alloys containing at least 5% by weight but less than 50% by weight of oxides, carbides, borides, nitrides, silicides or other metal compounds, e.g. oxynitrides, sulfides, whether added as such or formed in situ with carbides, nitrides, borides or silicides as the main non-metallic constituents
- C22C32/0052—Non-ferrous alloys containing at least 5% by weight but less than 50% by weight of oxides, carbides, borides, nitrides, silicides or other metal compounds, e.g. oxynitrides, sulfides, whether added as such or formed in situ with carbides, nitrides, borides or silicides as the main non-metallic constituents only carbides
Abstract
The invention provides a kind of method for sintering conductive powder and the equipment for performing methods described, this method includes：Powder is placed in electric insulation mould；Apply 100MPa to the pressure between 500MPa to powder；And apply sintering current density to powder with sintered powder under sintering voltage during sintering time.Before sintering current density is applied, during the soak time less than sintering time, under the activation voltage more than sintering voltage, apply the activation current density less than sintering current density to reduce the resistance of powder to powder.
Description
Technical field
The invention belongs to the field of the method for obtaining sintered component, methods described includes applying heat and pressure to powder
For finally obtaining compact components, especially, wherein obtaining heat via the electric current of conductive powder is forced past.
Background technology
ECAS (electric current assisted sintering, electric current assisted sintering) includes wherein machinery pressure
Power is combined to strengthen a series of consolidation methods of an interparticle bonding and densification with electric field and thermal field.Parent material can be powder
Or the form of green compact.The main purpose of the electric current of application is to provide the desired amount of resistance heat.
ECAS technologies can classify according to discharge time.Generally, 0.1s discharge time can be assumed as quick ECAS and
Threshold value between supper-fast ECAS.However, should avoid quick (fast) that names herein and in scientific literature often
Obscuring between the FAST acronyms (field activation/assisted sintering technology) run into.Here, quickly and easily referring to high disposal
Speed or reduction process time.
On the one hand, it is known that quick ECAS technologies depend primarily on current waveform and have different acronyms：SPS
(Spark Plasma Sintering, spark plasma sintering), PECS (Pulsed Electric Current
Sintering, pulse electric current sintering), RS (Resistance Sintering, electrical resistance sintering) etc..The process basis by
INOUE (US3241956A) is developed.Electric current applies usually as pulse, and it is also reported that can apply with different frequency
Various superimposed currents and the pressure in two stages are to increase densification.Application load is also described in US3508029A.This two
Kind of process be characterised by low intensive electric pulse (<1kA/cm2) and long duration circulation (from some seconds to some points
Clock).In addition, the manufacture of quick ECAS equipment is complicated, and need protective atmosphere (or vacuum).
On the other hand, supper-fast ECAS technologies are generally using one or for up to three times repetition (capacitor) electric discharges.Every time
Discharge period is less than 0.1s.Current impulse density can be about 10kA/cm2.Supper-fast ECAS is commonly known as electric discharge pressure
Real (EDC) or EFS (sintering is made in electro-forge).The representative illustration of these methods is explained in following patent：From Fais's
EP2198993A1, US4929415 and US4975412 from Okazaki.The subject matter of these methods is capacitor with prominent
Right uncontrolled mode discharges stored energy, and therefore they do not allow to adjust the power for being input to powder mass.
The inconsistent densification for the part for causing to manufacture using these consolidation processes using high current and high voltage and inhomogeneities, this
It is that because because the porosity between particle, surface oxidation, compacting or bonding cause the resistance of powder uneven, and many institutes are all
Know that electric current always follows most low-resistance path.Other problemses are that the size for the sample that can be manufactured is small and electric by high current and height
Press the spark in the electrode produced.
Other ultrafast processes use low-voltage equipment, such as by Cremer (US2355954), Knoess (US5529746) and
The patent of Bauer (US7361301) exploitations.Knoess and Bauer obtains good densification with highly conductive powder (such as iron and copper)
Change.Knoess using various very high currents (>100kA/cm2) pulse, and Bauer using about 1s sintering time, electric current
Intensity is less than 10kA/cm2Pulse, voltage be less than 10V.When manufacture high resistance sample when, due to powder high resistivity or
Due to the large scale of part, in fact it could happen that following problem：After closed circuit electric current can not be made to pass through whole material components.Therefore,
Using these technologies, due to using low-voltage, on the contrary it will not be possible to obtain consolidating for larger sample or the powder with higher electric resistivity
Knot.
The content of the invention
In order to overcome the shortcoming of prior art, the present invention proposes one kind and sinters conductive powder in air atmosphere to obtain
The method of sintered products, this method includes following series of steps：
A) powder is placed in electric insulation mould；
B) 100MPa is applied to the pressure between 500MPa to powder；And
C) sintering current density is applied to powder with sintered powder under sintering voltage during sintering time.
The method of the present invention includes：Between step b) and step c), during the soak time less than sintering time,
Under activation voltage more than sintering voltage, apply the activation current density less than sintering current density to reduce powder to powder
Resistance.
Activation current density and being applied to while applying pressure to powder for sintering current density perform.
Than step c) during short time than step c) in be used under the big voltage of the voltage that sinters, applied to powder
Plus activation current density produce oxide skin(coating) in following current discharge, the current discharge destruction powder surface, and
Bridge is set up between the particle of powder, so as to obtain the particle surface cleaned evenly and more, powder is flowed through it reduce electric current
Resistance so that powder of the sintering current density applied in the step c) in mould is more uniformly distributed.It therefore, it can
Sintering large-size components and the part being made up of the material with high resistivity.
Preferably, activation current density is more than 0.5kA/cm2, activation voltage is more than 10V, and soak time is less than
300ms, for producing low intensive current discharge under high voltages within the time significantly shortened, to ensure the uniform table of powder
Emaciated face oxygen and bridge is formed between particles.
According to the present invention, the time for removing activation current density and applying between sintering current density is less than 20ms to ensure
The optimal distribution of sintering current density.Most preferably, tightly (that is, just terminate after activation current density is applied in soak time
Apply sintering current density afterwards).
According to a preferred aspect of the present invention, activation current density and sintering current density are constant.
According to a preferred aspect of the present invention：
Apply activation current density by using the first power subsystem；
Apply sintering current density by using second source unit；And
First power subsystem and second source unit are operating independently.
The method of the present invention includes the control to two power subsystems, and this makes it possible to the optimization processing time and energy disappears
Consumption and installation cost.
In addition, it is allowed to the power being introduced into powder is programmed and monitored at any time, so as to allow applying work
The process is accurately and repeatedly controlled very much when both galvanic current density and application sintering current density.
Furthermore, it has been found that the accurate control realized by this method allows part dimension, its geometry and sinterable
Material type dramatically increase.
According to the preferred embodiment of the present invention：
Activation current density is included in 0.5kA/cm2To 5kA/cm2In the range of；
Activation voltage is included in the range of 10V to 100V；
Soak time is included in the range of 50ms to 300ms；
Sintering current density is included in 3kA/cm2To 15kA/cm2In the range of；
Sinter voltage and be less than 15V；And
Sintering time is included in the range of 500ms to 1500ms,
But these parameters must are fulfilled for following condition：The selective value for the sintering current density being applied on powder must be big
In the selective value of activation current density, and activate the selective value of voltage must be always greater than the sintering voltage applied.
According to the most preferred embodiment of the present invention：
Activation current density is included in 0.5kA/cm2To 4kA/cm2In the range of；
Activation voltage is included in the range of 10V to 100V；
Soak time is included in the range of 90ms to 200ms；
Sintering current density is included in 3kA/cm2To 10kA/cm2In the range of；
Sinter voltage and be less than 10V；And
Sintering time is included in the range of 500ms to 1500ms,
But these parameters must are fulfilled for following condition：The selective value for the sintering current density being applied on powder must be big
In the selective value of activation current density, and activate the selective value of voltage must be always greater than the sintering voltage applied.
Technical staff will select the exact value of these parameters for every kind of conductive powder, but keep firmly in mind be applied to a kind of conduction all the time
The activation current density of powder is necessarily less than applied sintering current density, and activates voltage more than sintering voltage.Therefore,
4kA/cm can not possibly be selected for activation current density2Value and for sintering current density select 3kA/cm2Value.This is same
Suitable for activation voltage and sintering voltage, wherein 10V activation voltage and 15V sintering voltage cannot be applied.Preferred real
Some examples of parameter selection are disclosed in the description for applying mode.
The invention further relates to a kind of equipment for being used to perform the sintering of conductive powder in air atmosphere, including：Electric insulation
Mould, it can be filled with powder；Two relative electrodes, it can be coupled to mould；Apply for the powder into mould
The device of pressure, and for providing the device of current density and voltage by electrode.It is close for providing electric current according to the present invention
The device of degree and voltage includes：
First power subsystem, it is arranged under activation voltage (living to powder offer activation current density by electrode
Change step)；And
Second source unit, it is arranged under sintering voltage (is burnt by electrode to powder offer sintering current density
Tie step),
Activation current density is less than sintering current density, and activates voltage more than sintering voltage.
According to the present invention, the equipment also includes：
For the device switched between the first power subsystem and second source unit；
For the activation current density for controlling to be provided by the first power subsystem and the duration of activation voltage (during activation
Between) device；And
For the sintering current density for controlling to be provided by second source unit and the duration of sintering voltage (during sintering
Between) device,
Sintering time is more than soak time.
This device for being specially designed for performing the inventive method can be realized with the business equipment of low cost.
In embodiments of the present invention, the first power subsystem is arranged to during the soak time less than 300ms
There is provided and be more than 0.5kA/cm2Activation current density and activation voltage more than 10V, within the time significantly shortened
Low intensive current discharge is produced under high voltage, to ensure the uniform outer surface deoxidation of powder.
In a preferred embodiment of the invention, the first power subsystem is configured to provide in 0.5kA/cm2To 5kA/cm2
Between activation current density and in 10V to the activation voltage between 100V, and second source unit is configured to provide
In 3kA/cm2To 15kA/cm2Between sintering current density and sintering voltage less than 15V.
According to preferred embodiment, equipment of the invention includes switching device, and it allows the first power subsystem of control and the
The startup of two power subsystems and deactivation so that preferably tight (just to terminate after activation current density is removed in soak time
Apply sintering current density afterwards), and preferably, between the startup of the deactivation and second source unit of the first power subsystem
Time is less than 20ms to ensure the optimal distribution of sintering current density.
First power subsystem may be configured to provide constant activation current density or constant activation voltage, and the
Two power subsystems may be configured to provide constant sintering current density.
Activation current density and the device of the duration of activation voltage for controlling to be provided by the first power subsystem can
The predetermined discharge time (soak time) in the range of 50ms to 300ms is included in control.
Sintering current density and the device of the duration of sintering voltage for controlling to be provided by second source unit can
The predetermined discharge time (sintering time) in the range of 500ms to 1500ms is included in control.
In a preferred embodiment, each power subsystem includes transformer and inverter.
Preferably, two power subsystems are by control unit control, and control unit is programmable logic controller (PLC).
Control unit can include：
For the device switched between the first power subsystem and second source unit；
For the activation current density and the device of the duration of activation voltage for controlling to be provided by the first power subsystem；With
And
For the sintering current density and the device of the duration of sintering voltage for controlling to be provided by second source unit.
Brief description of the drawings
In order to complete description and more fully understand that there is provided one group of accompanying drawing to the present invention to provide.The accompanying drawing
The part of this specification is formed, and shows embodiments of the present invention, it is not necessarily to be construed as the limitation present invention's
Scope, and only it is the example how present invention can perform.Accompanying drawing includes the following drawings：
Fig. 1 is the block diagram of the equipment according to preferred embodiment；And
Fig. 2 be the present invention method be applied to WC-Co powder when pressure and voltage/current time diagram.
Embodiment
Figure 2 illustrates with according to the present invention be used for obtain sintering WC-Co method embodiment it is corresponding when
Between pressure/current/voltage figure.
The process starts from the step being placed on conductive powder in electric insulation mould.
Then 100MPa is applied in mould to the pressure between 500MPa, it is preferred to use two pistons, in this feelings
Pressure is about 300MPa under condition.
Then activation step is performed, the activation step is to apply activation current density continuous activation under activation voltage
Time and performed by using the first power subsystem 2.As shown, in this step, low current density (about 2kA/ is applied
cm2) and high voltage (about 30V).Pulse is about 2/10ths seconds.
Then waiting step is performed, does not apply electric current and/or voltage in this step.The step is cutting for power subsystem
Change, i.e., switch to another power subsystem 3 from power subsystem 2.It by control unit 4 (is to compile in the current situation that stand-by period, which is,
Journey logic controller (PLC)) perform time needed for the switching.In fig. 2, switching time is about 2/10ths seconds.Technology
On can likely use single power subsystem, but with instantaneous variable electric current and voltage.However, for electric current and electricity
The control requirement of voltage level and discharge time will imply that extremely complex equipment, and this will cause this method on industrial level
It is uneconomical.
Then, appropriate sintering step is carried out, the sintering step is in the burning performed by using second source unit 3
Apply sintering current density under sintering voltage during the knot time.In this case, intensity is higher (about 10kA), but voltage drop
It is low to arrive 5V.
Apply current density using two relative electrodes.In embodiments, piston may be used as relative electrode.
As shown in figure 1, and according to preferred embodiment, the invention further relates to a kind of method for being used to perform the present invention
Equipment 1.
The equipment includes：
Device for applying electric current and from voltage to powder, described device is represented by power subsystem 2,3；And
Electric insulation mould 5 comprising conductive powder 6, the electric insulation mould 5 is in its end by for applying mechanical pressure
Two pistons close and yet forms both electrode 7.
As shown in figure 1, being the first power subsystem 2 for the device that electric current and voltage are provided for activation step, and it is used for
The device that electric current and voltage are provided for sintering step is second source unit 3.
First power subsystem 2, which is arranged to provide by electrode 7, is included in 0.5kA/cm2To 5kA/cm2Between activation
Current density and 10V is included in the activation voltage between 100V, and second source unit 3 is arranged to by electrode 7
Offer is included in 3kA/cm2To 15kA/cm2Between sintering current density and sintering voltage less than 15V.These scopes
Allow the conduction that most of commercial interests are sintered with individual machine (parameter of the machine must be set before sintering)
Powder is used to typically apply.
The equipment also includes：
For the device switched between the first power subsystem 2 and second source unit 3；
For the current density and the device of the duration of voltage for controlling to be provided by the first power subsystem 2；
For the current density and the device of the duration of voltage for controlling to be provided by second source unit 3；
The connector 23,33 of each in power subsystem 2,3 between the electrode 7 of mould 5；And
Apply the device of stressed piston in a mold for control.
Current density and the device of the duration of voltage for controlling to be provided by the first power subsystem 2 can control quilt
It is included in the predetermined discharge time (soak time) in the range of 50ms to 300ms, and for controlling by second source unit 3
The device of the current density of offer and the duration of voltage can control to be included in pre- in the range of 500ms to 1500ms
Determine discharge time (sintering time).
Each power subsystem 2,3 includes transformer 21,31 and inverter 22,32, and two power subsystems 2,3 are by single
Control unit 4 is controlled, and the single control unit 4 is preferably programmable logic controller (PLC) (PLC).
The PLC includes：
For the device switched between the first power subsystem 2 and second source unit 3；
For the electric current and the device of the duration of voltage for controlling to be provided by the first power subsystem 2；
For the electric current and the device of the duration of voltage for controlling to be provided by second source unit 3；And
Apply the device of stressed piston in a mold for control.
Now, the method for the present invention is applied to the specific example of different metal powder by description.
Example 1：WC-6Co/WC-10Co
Use WC-6Co the or WC-10Co pieces that disclosed device fabrication thickness is 16mm and a diameter of 22mm.Reunite
Powder be it is spherical, wherein particle size be less than 100 microns.
In activation step, 2kA/cm is applied to during 100ms to 200ms2To 4kA/cm2Between current density with
Activated powder.The activation step needs 15V to the voltage between 50V.
In subsequent sintering stage, 6kA/cm is applied to during 500ms to 1000ms2To 10kA/cm2Between electricity
Current density, to obtain the sample of densification under the voltage less than 10V.Between activation stage and sintering stage, 10ms is established
Minimum time.Apply 100MPa to 500MPa pressure at the very start from the process.
The density of the final piece measured by Archimedes method is about 13g/cm3To 14.8g/cm3.It can obtain with about
The complete fully dense sample of 1800HV30 to 2100HV30 hardness.
Example 2：Titanium
Use the titanium sheet that disclosed device fabrication thickness is 10mm and a diameter of 22mm.The shape of powder particle is not
Rule, wherein maximum particle size is about 75 microns.
In activation step, 1kA/cm is applied to during 90ms to 100ms2To 3kA/cm2Between current density with work
Change powder.Activation stage needs 10V to the voltage between 50V.
In sintering stage, 4kA/cm is applied to during 500ms to 1000ms2To 7kA/cm2Between current density,
To obtain the sample of densification under the voltage less than 10V.Between these activation stages and sintering stage, 10ms is established most
The small time.Apply 100MPa to 500MPa pressure at the very start from the process.
The density of the final piece measured by Archimedes method is about 3.5g/cm3To 4.4g/cm3.Complete cause can be obtained
Close sample.
Example 3：TiC-25Ni and TiC-25Fe
Use TiC-25Ni the and TiC-25Fe pieces that disclosed device fabrication thickness is 16mm and a diameter of 22mm.Group
Poly- powder is irregular, and wherein particle size is less than 30 microns.
In activation step, 1kA/cm is applied to during 100ms to 200ms2To 3kA/cm2Between current density with
Activated powder.The activation stage needs 15V to the voltage between 50V.
In subsequent sintering step, 6kA/cm is applied to during 500ms to 1000ms2To 9kA/cm2Between electric current
Density, to obtain the sample of densification under the voltage less than 10V.Between activation stage and sintering stage, establish 10ms's
Minimum time.Apply 100MPa to 500MPa pressure at the very start from the process.
The density of the final piece measured by Archimedes method is about 5.1g/cm for TiC-25Ni3To 5.5g/cm3, and
And be 5.1g/cm for TiC-25Fe3To 5.4g/cm3.Hardness can be obtained completely fine and close in about 1600HV30 to 2000HV30
Sample.
Example 4：Aluminium
Use the aluminium flake that disclosed device fabrication thickness is 12mm and a diameter of 12mm.Powder be it is irregular, its
Middle particle size is less than 150 microns.
In activation step, 0.5kA/cm is applied during 100ms to 200ms2To 2kA/cm2Between current density with
Activated powder.The activation stage needs 30V to the voltage between 80V.
In subsequent sintering stage, 3kA/cm is applied during 500ms to 1000ms2To 4kA/cm2Between electric current it is close
Degree, to obtain the sample of densification under the voltage less than 10V.Between activation stage and sintering stage, 10ms is established most
The small time.Apply 100MPa to 300MPa pressure at the very start from the process.
The density of the final piece measured by Archimedes method is about 2.5g/cm3To 2.7g/cm3。
Herein, term " comprising " and its derivative should not understand in the sense that exclusion, that is to say, that these arts
Language, which is not construed as excluding described and definition content, can include the possibility of other element, step etc..
Present invention is obviously not limited to embodiments described herein, and it is included in what claims were limited
The admissible any change of those skilled in the art in the case of in the general range of the present invention.
Claims (15)
1. a kind of sinter method of the conductive powder to obtain sintered products in air atmosphere, methods described includes following series step
Suddenly：
A) powder is placed in electric insulation mould；
B) 100MPa is applied to the pressure between 500MPa to the powder；And
C) sintering current density is applied to the powder to sinter the powder under sintering voltage during sintering time,
Characterized in that, between step b) and step c), during less than the soak time of the sintering time, more than institute
Under the activation voltage for stating sintering voltage, apply the activation current density less than the sintering current density to reduce to the powder
The resistance of the powder.
2. according to the method described in claim 1, wherein, the activation current density be more than 0.5kA/cm2, the activation voltage
More than 10V, and the soak time is less than 300ms.
3. according to any method of the preceding claims, wherein：
The application of the sintering current density and the sintering voltage is performed by using the first power subsystem (2)；
The application of the activation current density and the activation voltage is performed by using second source unit (3)；And
First power subsystem (2) and the second source unit (3) are operating independently.
4. according to any method of the preceding claims, wherein：
The activation current density is included in 0.5kA/cm2To 5kA/cm2In the range of；
The activation voltage is included in the range of 10V to 100V；
The soak time is included in the range of 50ms to 300ms；
The sintering current density is included in 3kA/cm2To 15kA/cm2In the range of；
The sintering voltage is less than 15V；And
The sintering time is included in the range of 500ms to 1500ms,
And wherein, the activation current density is less than the sintering current density, and the activation voltage is more than described burn
Junction voltage.
5. method according to any one of claim 1 to 4, wherein：
The powder is WC-6Co powder or WC-10Co powder；
The activation current density is included in 2kA/cm2To 4kA/cm2In the range of；
The activation voltage is included in the range of 15V to 50V；
The soak time is included in the range of 100ms to 200ms；
The sintering current density is included in 6kA/cm2To 10kA/cm2In the range of；
The sintering voltage is less than 10V；And
The sintering time is included in the range of 500ms to 1000ms.
6. method according to any one of claim 1 to 4, wherein：
The powder is titanium powder；
The activation current density is included in 1kA/cm2To 3kA/cm2In the range of；
The activation voltage is included in the range of 10V to 50V；
The soak time is included in the range of 90ms to 110ms；
The sintering current density is included in 4kA/cm2To 7kA/cm2In the range of；
The sintering voltage is less than 10V；And
The sintering time is included in the range of 500ms to 1000ms.
7. method according to any one of claim 1 to 4, wherein：
The powder is the mixture of TiC-25Ni powder and TiC-25Fe powder；
The activation current density is included in 1kA/cm2To 3kA/cm2In the range of；
The activation voltage is included in the range of 15V to 50V；
The soak time is included in the range of 100ms to 200ms；
The sintering current density is included in 6kA/cm2To 9kA/cm2In the range of；
The sintering voltage is less than 10V；And
The sintering time is included in the range of 500ms to 1000ms.
8. method according to any one of claim 1 to 4, wherein：
The powder is aluminium powder；
The activation current density is included in 0.5kA/cm2To 2kA/cm2In the range of；
The activation voltage is included in the range of 30V to 80V；
The soak time is included in the range of 100ms to 200ms；
The sintering current density is included in 3kA/cm2To 4kA/cm2In the range of；
The sintering voltage is less than 10V；And
The sintering time is included in the range of 500ms to 1000ms.
9. a kind of equipment (1) for being used to perform the sintering of conductive powder in air atmosphere, including：Be electrically insulated mould, and it can
Filled with the powder；Two relative electrodes, it, which can be coupled to the mould, is used for the powder into the mould
Apply current density；Stressed device is applied for the powder into the mould；And for being carried by the electrode
The device of current density of powering and voltage, it is characterised in that the described device for providing current density and voltage includes：
First power subsystem (2), it is arranged under activation voltage and provides activation current density to the powder；And
Second source unit (3), it is arranged under sintering voltage and provides sintering current density to the powder,
The activation current density is less than the sintering current density, and the activation voltage is more than the sintering voltage,
The equipment also includes：
For the device switched between first power subsystem (2) and the second source unit (3)；
For control by first power subsystem (2) provide the activation current density and the activation voltage it is lasting when
Between device；And
For control by the second source unit (3) provide the sintering current density and the sintering voltage it is lasting when
Between device,
The soak time is less than the sintering time.
10. equipment according to claim 9, wherein：
For control by first power subsystem (2) provide the activation current density and the activation voltage it is lasting when
Between described device can control to be included in the soak time in the range of 50ms to 300ms；And
For control by the second source unit (3) provide the sintering current density and the sintering voltage it is lasting when
Between described device can control to be included in the sintering time in the range of 500ms to 1500ms.
11. the equipment according to any one of claim 9 and 10, wherein, first power subsystem (2) can provide greatly
In 0.5kA/cm2Activation current density and activation voltage more than 10V.
12. the equipment according to any one of claim 9,10 and 11, wherein, first power subsystem (2) can carry
For in 0.5kA/cm2To 5kA/cm2Between activation current density and in 10V to the activation voltage between 100V, it is and described
Second source unit (3) can be provided in 3kA/cm2To 15kA/cm2Between sintering current density and sintering less than 15V
Voltage.
13. the equipment according to any one of claim 9 to 12, wherein, each power subsystem (2,3) includes transformation
Device (21,31) and inverter (22,32).
14. the equipment according to any one of claim 9 to 13, wherein, two power subsystems (2,3) and for described
Mould is applied stressed described device and controlled by control unit (4), preferably by PLC controls.
15. equipment according to claim 14, wherein, described control unit (4) includes：
For the device switched between first power subsystem (2) and the second source unit (3)；
For control by first power subsystem (2) provide the activation current density and the activation voltage it is lasting when
Between device；And
For control by the second source unit (3) provide the sintering current density and the sintering voltage it is lasting when
Between device.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| EP16382069.9 | 2016-02-19 | ||
| EP16382069.9A EP3208015B1 (en) | 2016-02-19 | 2016-02-19 | Method of sintering electrically conducting powders |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN107096919A true CN107096919A (en) | 2017-08-29 |
| CN107096919B CN107096919B (en) | 2021-04-06 |
Family
ID=55446727
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201710089756.1A Active CN107096919B (en) | 2016-02-19 | 2017-02-20 | Method for sintering conductive powder and apparatus for carrying out said method |
Country Status (5)
| Country | Link |
|---|---|
| US (1) | US20170259336A1 (en) |
| EP (1) | EP3208015B1 (en) |
| CN (1) | CN107096919B (en) |
| DK (1) | DK3208015T3 (en) |
| ES (1) | ES2738627T3 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111375758A (en) * | 2020-04-23 | 2020-07-07 | 王伟东 | Sintering method of titanium or titanium alloy powder |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP3702065A1 (en) * | 2019-02-28 | 2020-09-02 | Siemens Aktiengesellschaft | Sintering device with decoupled sinter pressure and sinter flow, method for producing an electric contact material using the sintering device, electric contact material and use of the electric contact material |
| CN111748717B (en) * | 2020-06-30 | 2021-06-08 | 马鞍山海华耐磨材料科技有限公司 | Wear-resistant casting made of metal-based ceramic composite material and machining process of wear-resistant casting |
Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3656946A (en) * | 1967-03-03 | 1972-04-18 | Lockheed Aircraft Corp | Electrical sintering under liquid pressure |
| JPH03236402A (en) * | 1990-02-13 | 1991-10-22 | Sumitomo Coal Mining Co Ltd | Electric discharge sintering apparatus |
| US5529746A (en) * | 1994-03-08 | 1996-06-25 | Knoess; Walter | Process for the manufacture of high-density powder compacts |
| CN1302707A (en) * | 2001-01-20 | 2001-07-11 | 昆明理工大学 | Plasma technology for activating sintered material |
| CN2471452Y (en) * | 2001-01-13 | 2002-01-16 | 昆明理工大学 | Plasma activating material sintering apparatus |
| US6612826B1 (en) * | 1997-10-15 | 2003-09-02 | Iap Research, Inc. | System for consolidating powders |
| CN1676250A (en) * | 2001-01-20 | 2005-10-05 | 昆明理工大学 | Nano zirconium oxide plasma activation sintering method |
| US20050237698A1 (en) * | 2004-04-23 | 2005-10-27 | Postage Bradley R | Reduced ESR through use of multiple wire anode |
| CN1959878A (en) * | 2005-11-02 | 2007-05-09 | 四川大学 | Method for preparing permanent magnetism block body of Nano crystal neodymium, boron |
Family Cites Families (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2355954A (en) | 1942-03-04 | 1944-08-15 | Hardy Metallurg Company | Powder metallurgy |
| US3241956A (en) | 1963-05-30 | 1966-03-22 | Inoue Kiyoshi | Electric-discharge sintering |
| US3508029A (en) | 1967-02-22 | 1970-04-21 | Lockheed Aircraft Corp | Servocontrol system for discharge sintering |
| US4975412A (en) | 1988-02-22 | 1990-12-04 | University Of Kentucky Research Foundation | Method of processing superconducting materials and its products |
| US4929415A (en) | 1988-03-01 | 1990-05-29 | Kenji Okazaki | Method of sintering powder |
| EP2198993B1 (en) | 2008-12-19 | 2012-09-26 | EPoS S.r.L. | Sintering process and corresponding sintering system |
-
2016
- 2016-02-19 ES ES16382069T patent/ES2738627T3/en active Active
- 2016-02-19 DK DK16382069.9T patent/DK3208015T3/en active
- 2016-02-19 EP EP16382069.9A patent/EP3208015B1/en active Active
-
2017
- 2017-02-19 US US15/436,844 patent/US20170259336A1/en not_active Abandoned
- 2017-02-20 CN CN201710089756.1A patent/CN107096919B/en active Active
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3656946A (en) * | 1967-03-03 | 1972-04-18 | Lockheed Aircraft Corp | Electrical sintering under liquid pressure |
| JPH03236402A (en) * | 1990-02-13 | 1991-10-22 | Sumitomo Coal Mining Co Ltd | Electric discharge sintering apparatus |
| US5529746A (en) * | 1994-03-08 | 1996-06-25 | Knoess; Walter | Process for the manufacture of high-density powder compacts |
| US6612826B1 (en) * | 1997-10-15 | 2003-09-02 | Iap Research, Inc. | System for consolidating powders |
| CN2471452Y (en) * | 2001-01-13 | 2002-01-16 | 昆明理工大学 | Plasma activating material sintering apparatus |
| CN1302707A (en) * | 2001-01-20 | 2001-07-11 | 昆明理工大学 | Plasma technology for activating sintered material |
| CN1676250A (en) * | 2001-01-20 | 2005-10-05 | 昆明理工大学 | Nano zirconium oxide plasma activation sintering method |
| US20050237698A1 (en) * | 2004-04-23 | 2005-10-27 | Postage Bradley R | Reduced ESR through use of multiple wire anode |
| CN1959878A (en) * | 2005-11-02 | 2007-05-09 | 四川大学 | Method for preparing permanent magnetism block body of Nano crystal neodymium, boron |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111375758A (en) * | 2020-04-23 | 2020-07-07 | 王伟东 | Sintering method of titanium or titanium alloy powder |
Also Published As
| Publication number | Publication date |
|---|---|
| US20170259336A1 (en) | 2017-09-14 |
| CN107096919B (en) | 2021-04-06 |
| DK3208015T3 (en) | 2019-07-29 |
| EP3208015A1 (en) | 2017-08-23 |
| ES2738627T3 (en) | 2020-01-24 |
| EP3208015B1 (en) | 2019-05-01 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP6811808B2 (en) | A method for manufacturing a support structure for supporting a three-dimensional object to be formed generatively. | |
| Samuel et al. | Power metallurgy tool electrodes for electrical discharge machining | |
| Orrù et al. | Consolidation/synthesis of materials by electric current activated/assisted sintering | |
| US10245640B2 (en) | Device and a method for consolidation of powder materials | |
| CN107096919A (en) | The equipment for sintering the method for conductive powder and performing methods described | |
| EP2198993B1 (en) | Sintering process and corresponding sintering system | |
| Liu et al. | An analysis of the discharge mechanism in electrochemical discharge machining of particulate reinforced metal matrix composites | |
| US3241956A (en) | Electric-discharge sintering | |
| WO2014109675A1 (en) | Method for producing a metal article from powdered material and apparatus for the implementation thereof | |
| EP2399696A1 (en) | Electrode manufacturing method and electric discharge surface treatment used therein | |
| JP4449847B2 (en) | Method of manufacturing discharge surface treatment electrode and apparatus for manufacturing the same | |
| CA2888299A1 (en) | Method and control unit for operating a plasma generation apparatus | |
| RU2007117508A (en) | METHOD FOR ELECTRIC HEATING ELEMENT FORMING BY METHOD AND / OR METAL-OXIDE MATERIAL FLAME SPRAYING METHOD | |
| Chalyi et al. | Heating of high current electric contacts under short-circuit shock currents | |
| Zhao et al. | Forming of micro-components by electrical-field activated sintering | |
| US11084112B2 (en) | Electrical discharge machine time slice power supply | |
| JPH03239509A (en) | Manufacture of molding die decorative plastics | |
| JP3377501B2 (en) | Thermal processing equipment | |
| Balaji et al. | Machining characteristics of aluminium oxide bioinert ceramics and optimization of ECDM process parameters | |
| JP2013177661A (en) | Power control automatic program | |
| Ha et al. | Energy-controlled Micro Electrical Discharge Machining for an Al 2 O 3-carbon Nanotube Composite | |
| Khan et al. | Surface modification by EDM using Co-Cr sintered powder metallurgy electrode | |
| JPH03236402A (en) | Electric discharge sintering apparatus | |
| JPH0841507A (en) | Electric sintering device | |
| UA106930C2 (en) | DEVICES FOR OBTAINING CONSOLIDATED POWDER MATERIALS |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |