CN203938607U - A kind of stupalith sintering oven - Google Patents

A kind of stupalith sintering oven Download PDF

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Publication number
CN203938607U
CN203938607U CN201420019268.5U CN201420019268U CN203938607U CN 203938607 U CN203938607 U CN 203938607U CN 201420019268 U CN201420019268 U CN 201420019268U CN 203938607 U CN203938607 U CN 203938607U
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sintering
electric field
stupalith
furnace body
heater
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CN201420019268.5U
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苏永东
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SUZHOU EVERBEST ENGINEERING CERAMICS Co Ltd
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SUZHOU EVERBEST ENGINEERING CERAMICS Co Ltd
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Abstract

The utility model discloses a kind of stupalith sintering oven, it is characterized in that, a kind of stupalith sintering oven comprises lower furnace body, thermopair, upper furnace body, battery lead plate, bench insulator, contact conductor, graphite packing, control electric field, rubber sealing boot, insulation ring seat, tensimeter, gas cylinder, air valve, compressor, gas inlet and outlet, impulse current generator, sintering controller and fixed feet; The field control sintering methods such as two, by base substrate being applied to the comprehensive action of the static pressure such as plasma discharging pulsed current, alternating electromagnetic field and gas, make both macro and micro stupalith be tending towards uniformity in heat energy, pressure and electromagnetic field transmission and direction; At stupalith microcosmic lattice, crystal boundary and dot matrix, there is even, isotropic sintering, thereby realize the raising of stupalith sintering properties.

Description

A kind of stupalith sintering oven
Technical field
The utility model relates to a kind of superhard wear stupalith manufacturing technology field, is specifically related to a kind of sintering process and technical equipment of stupalith, particularly a kind of stupalith sintering oven and etc. static-pressure field control plasma agglomeration method.
Background technology
Along with the develop rapidly of electronic industry and space industry in recent years, the manufacturer of ceramic part is also more and more.Particularly the development of superhard wear stupalith is faster, yet supplementary material formula, manufacture craft, moulding and the sintering method of superhard wear stupalith play a part very crucial to the quality of superhard wear stupalith and performance.Different according to product structure, specification, precision and performance, the conventional forming method of prior art has: the forming methods such as compression moulding, roll forming, extrusion molding, injection forming, hot-injection molding, injection molding and static pressure method.The new forming technique that development in recent years is got up: in-situ consolidation forming technology, rapid shaping technique and nano material forming technique; The conventional sintering method of prior art has: pressureless sintering, liquid phase sintering, reaction sintering, explosive sintering method, HIP sintering, microwave sintering method, laser sintered method, discharge plasma sintering method.
The sintering of pottery must possess two primary conditions: (1) exists the chance of material migration; (2) there is a kind of energy, as heat energy, promote and maintain the migration of material.The technology such as existing solid state sintering, liquid phase sintering, reaction sintering, the material structure utilizing and the motivating force of sintering are different, have their own characteristics each; Main sintering mechanism is liquid phase sintering and solid state sintering; The sintering of traditional ceramics and most electronic ceramics sintering depend on liquid phase sintering, viscous flow and dissolve deposition process again; The sintering of high-strength structure pottery be take solid state sintering as main, by crystal boundary, spreads or material migration is carried out in dot matrix diffusion, realizes sintering.
In prior art, forming method and sintering method, aspect the migration of material, use be the diffusion of External Force Acting or interior microscopic; Selected energy mode is heat energy, luminous energy, polarization energy, electric energy; The external pressure providing, take isostatic pressing technology as optimal selection; The energy mode providing be take plasma discharge technology as optimal selection; And the diffusion of inner crystal boundary and dot matrix is basic identical; The effect of its energy and external force is all subject to the restriction of conduction, directivity, functioning efficiency and can not have given play to effect completely, the defect place of existing moulding that Here it is and sintering technology development.Traditional method tends to cause material internal lack of homogeneity, formed precision low, and the problem such as amount of machining is large, causes stupalith defect many, and reliability is low, manufacturing cost is high, has seriously hindered high-performance ceramic industrialization and application.
Sintering is a kind of technology of utilizing heat energy to make powder green bodies densification.Its definition refers to that vesicular ceramic body is under hot conditions, the densification process that surface-area reduces, porosity reduces, mechanical property improves; The Macrocosm and microcosm mechanism of action and the Changing Pattern of base substrate in high temperature sintering process, is to improve the quality of products, and reduces fuel consumption, obtains the prerequisite of good economic benefit; Total be exactly the minimizing of sintering motivating force interfacial energy, the reduction of the densification of stupalith, grain growth, interfacial energy.
Pressureless sintering: simple high temperature sintering method, shortcoming is the effect that there is no external force, in simple base substrate, heat energy is on Macrocosm and microcosm impact in stupalith; Shortcoming is: pulling out gas and lattice, crystal boundary, to reset densification inadequate.
Hot pressed sintering: hot pressed sintering is blank to be exerted pressure in sintering process simultaneously, has accelerated the process of densification.So the temperature of hot pressed sintering is lower, sintering time is shorter.The existing many decades of hot-pressing technique is historical, for the preparation of wolfram varbide and the fine and close part of tungsten powder, has been widely used in the production of pottery, powder metallurgy and matrix material now the earliest; Shortcoming is: mechanical system is exerted pressure, and institute's applied pressure has directivity, and the pressure direction of macroscopic view causes the structural pressure of microcosmic inhomogeneous, makes sintered compact performance homogeneity bad.
HIP sintering is that powder compact or the powder that packs jacket into are packed in high pressure vessel, makes powder stand the effect of high temperature and equalized pressure, is sintered into fine and close part.Using gas or liquid as pressure medium, make material (powder, base substrate or sintered compact) in heat-processed, stand each to balanced pressure, by the acting in conjunction of high temperature and high pressure, promote the densification of material, shortcoming is: by gas or liquid, workpiece is exerted pressure, the pressure of described gas or liquid is that isotropy equates, but described gas or liquid be by identical pressure-acting on the surface of workpiece, variation along with Workpiece structure and thickness, inside workpiece everywhere, the pressure that experience in the place of different structure shape is diverse, workpiece surface has been subject to identical pressure-acting in other words, but at inside workpiece or different depths, inside or microcosmic pressure that the identical pressure in surface produces are diverse, so simple hot isostatic pressing, it is the sintering under identical external pressure and identical outside thermodynamic activity, the heterogencity of sintered compact interior microscopic form will inevitably be caused, also the defect on ceramic material property will be caused.
Discharge plasma sintering is a kind of type material process of preparing that development in recent years is got up.Pulse electric current sintering is otherwise known as.The principal feature of this technology is to utilize body heating and surface active, realizes the supper-fast densification sintering of material; Shortcoming is: the product after sintering there will be performance profile inhomogeneous along current electric fields direction, because electric field magnetic line of force distributes, can produce Territorial Difference to stupalith; Utilize microcosmic heating plasma, microtexture lacks pressure-acting; The electric discharge applying or pulsed current have strong directivity or polarity, in base substrate, can form current channel Huo Shan road phenomenon, make the homogeneity of integral sintered body microtexture bad, cause sintered compact overall performance difference or directional difference.
Chinese patent CN1478757A, discloses a kind of method of preparing high-purity block titanium alumina-carbon material with discharge plasma sintering; Patent CN1817434A, discloses a kind of method of spark plasma sintering crystallization cubic boron nitride sintered body; All to utilize discharge plasma sintering technique, base substrate axially apply plasma pulse electric current, to the internal performance of sintered compact, can produce like this Gradient distribution difference of microcosmic.
Chinese patent CN103343249A, a kind of preparation method of electric field driven original position grade thermoelectric material is disclosed, the method utilizes directed resistance sintering to prepare grade thermoelectric material, make thermoelectric material under the effect in electric field and temperature field, the inner particles of material forms directivity Gradient distribution.
In sum, existing sintering method, pressure apply with the generation of transmission, heat with transmit the effect that does not all well realize the isotropy uniformity of whole workpiece sintering body, so, certainly can there is defect in various degree in institute's sintering stupalith out on the properties of Macrocosm and microcosm; In the directivity of pressure, heat energy, control the space that still exists technology to improve.
Utility model content
For solving the problems of the technologies described above, the utility model provide a kind of stupalith sintering oven and etc. static-pressure field control plasma agglomeration method, be called for short two control sintering that wait, ceramic sintering technology is combined with electric field controls technology, hot isostatic pressing and discharge plasma sintering technique are merged mutually, and electromagnetic field control techniques and the method for novelty design plasma discharging process, thereby improving pressure in existing sintering technology applies and transmits, heat energy produces the defect with transmission, make the pressure of both macro and micro, temperature, electric field is in controlled variation, formation microcosmic is truly respectively to homogeneity, control and the static pressure such as given play to, put ionic discharge, electromagnetic field is controlled the advantage of sintering, under electromagnetic field is controlled, plasma discharging is flow to horizontal deflection and movement, thereby the successful sintering of implementation structure pottery, obtain quality structure stupalith.
The gordian technique point that the utility model need to solve, that isostatic pressing technology is combined with discharge plasma sintering technique, and use electromagnetic field control techniques to carry out field control and skew to the pulsed current in discharge plasma sintering, overcome the deficiency of discharge plasma sintering, omnibearing stereo formula is burnt thoroughly, crystal boundary and dot matrix, Macrocosm and microcosm acting in conjunction, implementation structure forming process of ceramics and sintering technology new development.
For achieving the above object, the technical solution of the utility model is as follows: a kind of stupalith sintering oven and etc. static-pressure field control plasma agglomeration method, comprise ceramic body preparation, a control sintering oven such as two, ceramic sintered bodies processing, a control sintering method such as two, it is characterized in that:
Described ceramic body preparation, comprises that raw and auxiliary material, proportioning components, blank preparation, blank mix, prepared by powder, powder grinds, powder mixes and compression molding; Described raw and auxiliary material is one or more the mixture in natural mineral powder, oxide powder, carbide powder or nitride powder, and auxiliary agent: properties-correcting agent, lubricant, fluidizer etc., described additive is MgO, Y 2o 3, La 2o 3, ZrO 2in a kind of, or any two mixture wherein, or any three kinds of mixtures wherein; Described additive addition is 0.01%---0.5%.
According to proportioning components, prepare; By the raw material preparing carry out preliminary ground and mixed, high-pressure homogeneous after, through the spray tower granulation of dusting, through the powder dusting after granulation, through three-dimensional hybrid shredder ground and mixed, obtain uniform ceramic material powder, ceramic material powder is loaded in the mould of component to be processed, through shaped by fluid pressure, obtains the blank of compression molding.
Described two field control sintering oven that waits comprises that lower furnace body, thermopair, upper furnace body, battery lead plate, bench insulator, contact conductor, graphite packing, workpiece, cooling water outlet, control electric field, rubber sealing boot, insulation ring seat, tensimeter, gas cylinder, air valve, compressor, gas inlet and outlet, impulse current generator, sintering controller, cold water inlet, fixed feet, electric field go between and tongued and grooved flanges.
Described upper furnace body and lower furnace body form a control sintering body of heater such as two by tongued and grooved flanges, and described body of heater is provided with cooling water sandwich, and lower furnace body side is provided with cold water inlet, and upper furnace body side is provided with cooling water outlet, for adjusting and the control of furnace body temperature; Described upper furnace body side is provided with thermocouple probe, for temperature in body of heater is carried out to Real-Time Monitoring.Described body of heater inner top and bottom are respectively arranged with bench insulator, on described bench insulator, be provided with battery lead plate, described battery lead plate is connected with body of heater external pulse current generator by contact conductor, produces pulsed current, and then workpiece is carried out to discharge plasma sintering by impulse current generator; Described battery lead plate is upper and lower two, between described upper and lower two electrode plate, be provided with rubber sealing boot, in described rubber sealing boot, be filled with graphite packing, the effect of fixing internal workpiece and On current is played in described graphite packing, and described graphite packing center is mounted with workpiece to be sintered;
Described lower furnace body inside is provided with a plurality of control electric fields, described control electric field is flat structure, polylith is controlled the even annular of electric field and is arranged in body of heater middle part, described control electric field is by the dead ring seat supports of its bottom, described insulation ring seat is supported by a plurality of fixed feet, described fixed feet is fixedly welded on inboard wall of furnace body, described insulation ring seat and fixed feet are welded and fixed, in described insulation ring seat and fixed feet, be provided with inner sleeve, for the electric field of controlling electric field being drawn to body of heater outside, and be connected with sintering controller; Described workpiece to be sintered, is embedded in the middle of graphite packing.
Described body of heater is sealed high-voltage resistant structure, its bottom is provided with gas inlet and outlet, described gas inlet and outlet, be connected with gas cylinder with compressor respectively, between described gas inlet and outlet and compressor, gas cylinder, be provided with tensimeter and air valve, switch or relief pressure that described air valve is carried for controlling gas; In the time of in gas is passed into body of heater, body of heater inside produce high pressure, and the rubber seal that described high pressure puts in stove puts, and then pressure is put on graphite packing and workpiece to be sintered.
Described body of heater is outside equipped with impulse current generator and sintering controller, described contact conductor, electric field lead-in wire, thermopair are all communicated with sintering controller, described impulse current generator is communicated with electrode outlet line, by sintering controller, sintering process process is controlled, realized two control sintering that wait of stupalith base substrate.
Described ceramic sintered bodies processing, comprises the demoulding of sintered compact blank, blank shaping, roughing, precision work, component polishing and component finished product; Ceramic body two wait a control sintering oven in after sintering, workpiece becomes sintered compact, sintered compact is taken out from the field control sintering ovens such as two, after graphite packing collection and treatment, again utilize, the sintered compact demoulding and shaping, the workpiece of sintering is carried out to roughing and precision work by technological standards requirement, then grind and polishing, obtain component finished product.
Described twoly wait field to control sintering method to be: ceramic powder loads in rubber cuff or ceramic part is imbedded in powdered graphite; Pack two control sintering oven that wait into, pass into protective gas and apply isostatic pressure, according to different stupaliths, the gaseous tension applying is 10---100MPa; According to the actual requirement of material, apply pulse plasma electric current, according to temperature rise rate, be 70 ℃---700 ℃/min, control two temperature parameters that wait a control sintering oven; Adjust with control annular simultaneously and control the intensity of electric field and alternately variation, rising along with temperature in stove, the intensity of voltage stabilizing pulsed current can improve gradually, and the intensity of described control electric field also increases, guarantee peripheral electric field to the effect of base substrate inside plasma state material in significant condition; When the temperature in sintering oven reaches sintering temperature, common sintering temperature region is 1000 ℃---2000 ℃; Keep temperature 1min---25min; According to temperature conditions in sintering oven, by increasing pulsed current, increasing peripheral control strength of electric field, or sintering oven is carried out to cooling process, control the temperature variation in sintering process; After being incubated, close impulse current generator switch, closing control electric field switch, two control sintering oven naturally cooling or cooling by cooling sandwith layer that wait, after system cooling, release; From the field control sintering ovens such as two, take out sintered compact, carry out roughing and precision work.
The stupalith of the utility model institute sintering, bending strength or reach 500---900MPa; Fracture toughness property can reach 5---10MPam 1/2; Density can reach more than 99.0; Vickers' hardness can reach 20---50GPa.
Operating process of the present utility model is: according to working specification, pack workpiece to be sintered into two grade in a control sintering oven, by furnace sealing and adjust parameters to original state, connect and control power supply, check whole sintering system, open source of the gas, open compressor and control air valve, exert pressure to body of heater inside, when furnace pressure reaches preset pressure, open impulse current generator, progressively add load electric current to power-on and power-off pole plate, voltage stabilizing pulsed current is by graphite district, and act on base substrate to be sintered, because pulsed current causes the inner plasma discharging that occurs of base substrate, and heat up rapidly, reach after sintering temperature, inside workpiece and outside all obtain pulse current discharging effect, the static pressure External Force Actings such as generation and the effect of pulsed current internal discharge, in the time of sintering, sintering controller is controlled many groups electric field of annular spread, workpiece is applied to pulsed, the electric field action of alternation, by the impact of pulse alternating electric field, cause pulsed current and the electromagnetic field environment of inside workpiece, the power of following external electrical field changes with direction of an electric field and changes, synchronously carry out in real time multi-angle, multi-direction variation, thereby realize between inside workpiece lattice, between crystal boundary, melt between body, between molten matter and solvent, between solid phase and liquid phase, between gas phase and liquid phase, there is complicated exchange and fusion, and the specific surface area between ceramic particle and internal energy are fully optimized, thereby obtain high quality high performance structural stupalith.
Described two control sintering method that waits is at the inner Omnidirectional heating of body of ceramic material, Macrocosm and microcosm at material carries out whole surface activation, in inner phase change, lattice variations, crystal boundary changes and draws in gas process, the whole mode of action is three-dimensional, multi-direction, carry out at many levels, therefore at electric field, apply direction and changes of magnetic field effect, heat energy produces and propagates, under impressed pressure and inner moment plasma discharge pressure acting in conjunction, the general effect embodying is exactly in sintering process, each of Macrocosm and microcosm is to homogeneity and consistence, thereby make sintered compact obtain excellent ceramic material property performance, and the performance uniformity of the performance of the stupalith obtaining in all directions.
Describedly two wait the mechanism that sintering method is controlled in field to be: solid state sintering and liquid phase sintering are also deposited, microcosmic plasma discharge produces moment microexplosion and plasma gas phase, so in whole sintering process, solid phase, liquid phase, gas phase deposit under microstate, under electric field and magnetic field alternation effect, externally wait under static pressure and inner microexplosion pressure, thermal energy transfer makes ceramic lattice, crystal boundary, surface, interface under microstate that quick variation all occur uniformly.Under microstate, solid-state, liquid, gaseous state and the comprehensive action of plasma state material, reciprocal effect, microexplosion, micro-sudden strain of a muscle, micro-melting betide multi-directionly, have realized heat energy and have produced and the homogenizing of transmitting, electric field and magnetic field discharge homogenizing, the rearrangement restructuring homogenizing of microcosmic ceramic particle.
Described control electric field is at least set to two, and symmetrical annular is arranged in the periphery of workpiece to be sintered, the electric field that symmetry is circular layout, formed the three-dimensional induction areas that affects workpiece to be sintered, for upper/lower electrode plasma discharging pulsed current, produce huge effect, and there is synchronous displacement along with the alternation in exterior annular stereoscopic electric magnetic field, this multidirectional pulsed current displacement has produced the reactive force of multi-C stereo in microtexture; Under the control of sintering controller, control electric field and can change intensity, also may change direction of an electric field, more can change the symmetrical form of electric field, this diverse external electric field influence mode is the reason of the good sintering of stupalith.
Conventionally gas or liqu id plasmas are between electrode, make medium-gas or liquid, as nitrogen or air etc. by high current intensity, be ionized into negatively charged ion and positively charged ion, plasma inside is the aggregate of zwitterion, and totally keeps electric neutrality, is called plasma body; Described plasma body is along the electric field forming between electrode, i.e. magnetic line of force areal distribution; In conventional plasma agglomeration, be that electric field electrode is arranged to stupalith both sides, and electrode is directly contacted with material to be sintered, guarantee current lead-through; During sintering, on electrode, apply large strength of current, by electrode, convey electrical current in ceramic body to be sintered, when strong current is passed through ceramic body to be sintered, conducting material in ceramic body, in solid-state crystal boundary and microcosmic dot matrix region, is dissociated into isoionic state, and produces high temperature.
Action principle of the present utility model: in micro, electric discharge makes microcosmic particle produce plasma state, and occurs the microcosmic plasma clustering collective of High Temperature High Pressure; Under pulsed current and additional electromagnetic field effect, microcosmic plasma body is moved, distortion, microexplosion, micro-sudden strain of a muscle etc.; Microcosmic plasma body moving, distortion, microexplosion and micro-flashing in journey, electron opaque material is had an immense impact on, thermal energy transmits fast, high field polarization is torn, high pressure, high temperature and high magnetic field intensity; After the field control conversion of moment, the migration of the melt of microcosmic part, decompression, cooling, make system transform towards more stable state; Macroscopic field control makes microcosmic plasma body generation remotely migrating, the population equilibrium of increase system, microcosmic plasma body is subject to the restriction of microcosmic crystal boundary and dot matrix, microexplosion, micro-sudden strain of a muscle and a control effect, can force microcosmic plasma body to break through the potential energy barrier of crystal boundary and dot matrix, thereby obtain the good sintering of ultra-hard abrasive material, greatly improve the property indices of ultra-hard abrasive material.
The mechanism of the utility model field control techniques: owing to having used electric field controls technology, in original sintering process, outside plasma electrode, be provided with control electric field, in plasma agglomeration process, by extra electric field, solid state plasma body is applied to electric field influence effect, the plasma body producing during sintering, will, at originally fixing crystal boundary region and dot matrix region isoionic state particle, be offset, vibrate, recombinate; The variation of the skew that this solid state plasma occurs under DC Electric Field, vibration, restructuring, on region, be that stereo directional occurs, the amount of skew and vibration is subject to the restriction of electric field strength, and the action direction that the direction of skew and vibration is also subject to extra electric field affects; Restructuring changes relevant with dot matrix microenvironment to the crystal boundary of solid state plasma, the component of the temperature in micro, adjacent crystal boundary and dot matrix, the kind of non-electric conductivity particle are all relevant with character, and final result is: under the effect of external electric field, skew, vibration and restructuring that solid state plasma occurs, accelerated the speed of plasma agglomeration stupalith, improved the quality of plasma agglomeration stupalith, improve the properties of plasma agglomeration stupalith, increased hardness, wear resistance, preservative property of stupalith etc.
The combination of the utility model isostatic pressing technology and plasma sintering technique, not only when stupalith sintering, the variation of the plasma body of generation microtexture and the micro-skew of various microcosmic, vibration, restructuring, but also can be to wait static pressure mode, in macroscopic view, plasma applies huge pressure, by macroscopical hydrostatic pressure, the high pressure action of plasma generation to solid-state lower microcosmic liquefaction, makes stupalith to be sintered be subject to the impact of another reactive force.
The feature of this novel overall technical scheme is: (1) microcosmic plasma body moment high temperature, and by high temperature transferring heat energy radiation towards periphery, affect non-electricity and lead particle, form moment melting partial liquid phase region; (2) under the effect of microcosmic local plasma, form localized liquid stupalith region, it is the body region of microcosmic plasma body, formation due to partial liquid phase region, changed the solid-state balance of microcosmic regional area, and by partial liquid phase region, adjacent solid matter is exerted one's influence, improve the bonding tightness of stupalith; (3) under External Electrical Field, there is skew, vibration, the restructuring of crystal boundary and dot matrix in microcosmic crystal boundary and dot matrix, is the key of stupalith sintering and moulding; (4) change direction of extra electric field and change frequency effect, make above-mentioned each factor on the stereo directional of solid-state and partial liquid phase stupalith, constantly change and break through, and at each independently between regional area, formation punctures, micro-sudden strain of a muscle, microexplosion, electric discharge, resonance etc. micro-variations, bulk ceramics material is had on solid space to be homogenized, and near the non-conductive particle directly having influence on, be stupalith can be between different components in conjunction with and form the important factor of superhard wear high performance material; (5) the hydrostatic pressure effect of macroscopic view, make the outside isostatic pressure effect that waits sintered ceramic material to be continued, and the partial liquid phase region in solid-state ceramic material is exerted an influence, the skew of localized region, vibration, recombinate and puncture, the electrical phenomena such as micro-sudden strain of a muscle, microexplosion, electric discharge, resonance all produces more effectively promoter action, lasting isostatic pressure is constantly to change or stupalith regional area, microcosmic, submicroscopic region that moment occurs provide and tighten and the propulsion source of closely assembling; (6) controlled external electric field, peripheral distribution mode at strength of electric field, direction of an electric field, electric field change frequency, electric field, all controllable, directly have influence on the variation of stupalith Macrocosm and microcosm structure, the direction of the generation of the transmission of reciprocity static pressure, the transmission of high temperature heat, crystal boundary and dot matrix breakthrough, micro-sudden strain of a muscle microexplosion, skew vibration and restructuring has all played crucial effect; (7) the field control techniques of the static pressure such as gas or liquid and extra electric field acts on stupalith to be sintered, but do not affect the body of stupalith, solid-state under microstate, liquid, gaseous state and plasma state coexist, electric field magnetic field interacts, comprehensive action is also one of feature of the present utility model.
Pass through technique scheme, the beneficial effect of technical solutions of the utility model is: waiting static pressure three dimensional field control discharge plasma sintering is the plasma state based on material itself and generating heat, be essentially different with type of heating, polarization energy mode, luminous energy mode by external heat source, plasma discharging is compared and is had obvious advantage and feature with conventional energy presentation mode, as high in efficiency, capacity usage ratio is high, pollution-free, can whole rapid heating, sintering temperature reduces, the uniform microstructure of material etc.(1) heating and sintering velocity are exceedingly fast.The traditional heating of material is that by sample conduction from outward appearance to inner essence, to reach temperature even.Therefore due to the poor thermal conductivity of most stupaliths, heating and sintered ceramic need for a long time, generally in hour, large component institute's time spent is just longer.Two sintering such as grade are that material internal integral body heats simultaneously, heat-up rate is fast, thereby greatly shortened sintering time, the sintering to some stupaliths particularly, from being reduced in several days even several weeks of past, use two several minutes magnitudes that wait sintering, thereby greatly improved the utilization ratio of production efficiency and the energy.(2) instantaneity and pollution-free.In the sintering processes such as two owing to not passing through thermal conduction, thereby there is no thermal inertia, there is instantaneity, can instantaneous break thermal source and heating in time, embodied feature energy-conservation and that be easy to control.Meanwhile, two sintering that wait can not pollute the material of institute's sintering, can be conveniently implemented in the sintering under vacuum and various atmosphere and pressure, can not look like oil firing, gas, coal etc. yet and produce obnoxious flavour contaminate environment in sintering process.(3) energy-efficient.The sintering temperatures such as two are compared with normal sintering temperature, and maximum cooling extent can reach 500 left and right; The efficiency that is generally transformed into heat energy from plasma energy can reach more than 90%, in addition twoly waits the time of sintering short, therefore can greatly reduce energy consumption.(4) selective sintering.For heterogeneous mixing material, due to the difference of different media plasma ability, the plasma intensity of generation is different, and heat effect is also different, utilizes this point to carry out selective sintering to matrix material.(5) improve microstructure and the macro property of stupalith.Because the speed of two sintering such as grade is fast, the time is short, thereby avoid the abnormal growth of crystal grain in sintering process, finally can obtain the superfine crystal particle structural ceramic material with high strength and toughness.(6) moulding and sintering can be realized a step and complete, the regulation and control of gas-static and external electric field and plasma agglomeration combine, and make the moulding of ceramic structure material and sintering can realize a step and complete, and have improved efficiency, saved cost, closed product performance and obtain tremendous increase.(7) the utility model makes the moulding of stupalith and sintering shorten process time and cycle, thereby output in enormous quantities, raise labour efficiency, and the competitive power of increase enterprise.
Accompanying drawing explanation
In order to be illustrated more clearly in the utility model embodiment or technical scheme of the prior art, to the accompanying drawing of required use in embodiment or description of the Prior Art be briefly described below, apparently, accompanying drawing in the following describes is only embodiment more of the present utility model, for those of ordinary skills, do not paying under the prerequisite of creative work, can obtain according to these accompanying drawings other accompanying drawing.
Fig. 1 be the disclosed a kind of stupalith sintering oven of the utility model embodiment and etc. static-pressure field control plasma agglomeration method structural representation;
Fig. 2 be the disclosed a kind of stupalith sintering oven of the utility model embodiment and etc. static-pressure field control plasma agglomeration method A-A sectional view schematic diagram;
Fig. 3 be the disclosed a kind of stupalith sintering oven of the utility model embodiment and etc. static-pressure field control plasma agglomeration method process flow diagram;
Fig. 4 be the disclosed a kind of stupalith sintering oven of the utility model embodiment and etc. static-pressure field control plasma agglomeration method technical process mark figure;
Fig. 5 is the disclosed a kind of stupalith sintering oven electric field structure figure schematic diagram of the utility model embodiment 2;
Fig. 6 is the disclosed a kind of stupalith sintering oven electric field structure figure schematic diagram of the utility model embodiment 3.
Numeral and the represented corresponding component title of letter in figure:
1. raw and auxiliary material 2. proportioning components 3. blanks are prepared 4. blanks mixing
5. powder is prepared 6. powders and is ground 7. powders and mix 8. compression moldings
9. the control sintering 10. blank demoulding 11. blank shaping 12. roughing such as pair grade
13. precision work 14. component polishing 15. component finished product 16. lower furnace bodies
17. thermopair 18. upper furnace body 19. battery lead plate 20. bench insulators
21. contact conductor 22. graphite packing 23. workpiece 24. cooling water outlets
25. control electric field 26. rubber sealing boot 27. insulation ring seat 28. tensimeters
29. gas cylinder 30. air valve 31. compressor 32. gas inlet and outlets
33. impulse current generator 34. sintering controller 35. cold water inlet 36. fixed feet
37. electric fields, 38. tongued and grooved flanges that go between
Embodiment
Below in conjunction with the accompanying drawing in the utility model embodiment, this novel technical scheme is described, obviously, described embodiment is only the utility model part embodiment, rather than whole embodiment.Embodiment based in the utility model, those of ordinary skills are not making the every other embodiment obtaining under creative work prerequisite, all belong to the scope of the utility model protection.
According to Fig. 1, Fig. 2, Fig. 3 and Fig. 4, the utility model provide a kind of stupalith sintering oven and etc. static-pressure field control plasma agglomeration method, comprise ceramic body preparation, a control sintering oven such as two, ceramic sintered bodies processing, a control sintering method such as two, it is characterized in that:
The preparation of described ceramic body, comprises that raw and auxiliary material 1, proportioning components 2, blank preparation 3, blank mix 4, powder prepares 5, powder grinds 6, powder mixes 7 and compression molding 8; Described raw and auxiliary material 1 is one or more the mixture in natural mineral powder, oxide powder, carbide powder or nitride powder, and auxiliary agent: properties-correcting agent, lubricant, fluidizer etc., according to proportioning components 2, prepare;
Preferably, described additive is: ZrO 2, adding per-cent is 0.25%;
By the raw material preparing carry out preliminary powder grind 6 mix, high-pressure homogeneous after, through spray tower, dust and prepare 5 granulations, through the powder dusting after granulation, through three-dimensional hybrid powder, grind 6 machine ground and mixed, obtain uniform ceramic material powder, ceramic material powder is loaded in the mould of component to be processed, through shaped by fluid pressure, obtains the blank of compression molding 8.
Describedly two wait field control sintering oven to comprise lower furnace body 16, thermopair 17, upper furnace body 18, battery lead plate 19, bench insulator 20, contact conductor 21, graphite packing 22, workpiece 23, cooling water outlet 24, control electric field 25, rubber sealing boot 26, the ring seat 27 that insulate, tensimeter 28, gas cylinder 29, air valve 30, compressor 31, gas inlet and outlet 32, impulse current generator 33, sintering controller 34, cold water inlet 35, fixed feet 36, electric field go between 37 and tongued and grooved flanges 38; It is characterized in that:
Described upper furnace body 18 forms two control sintering body of heater that wait with lower furnace body 26 by tongued and grooved flanges 38, described body of heater is provided with cooling water sandwich, lower furnace body 16 sides are provided with cold water inlet 35, and upper furnace body 18 sides are provided with cooling water outlet 24, for adjusting and the control of furnace body temperature; Described upper furnace body 18 sides are provided with thermopair 17 probes, for temperature in body of heater is carried out to Real-Time Monitoring.Described body of heater inner top and bottom are respectively arranged with bench insulator 20, on described bench insulator, be provided with battery lead plate 19, described battery lead plate 19 is connected with body of heater external pulse current generator 33 by contact conductor 21, by impulse current generator 33, produce pulsed current, and then workpiece 23 is carried out to discharge plasma sintering; Described battery lead plate 19 is upper and lower two, between described upper and lower two electrode plate 19, be provided with rubber sealing boot 26, in described rubber sealing boot 26, be filled with graphite packing 22, the effect of fixing internal workpiece 23 and On current is played in described graphite packing 22, and described graphite packing 22 centers are equipped with workpiece 23 to be sintered.
Described lower furnace body 16 inside are provided with a plurality of control electric fields 25, described control electric field 25 is flat structure, polylith is controlled the even annular of electric field 25 and is arranged in body of heater middle part, described control electric field 25 is supported by the insulation ring seat 27 of its bottom, described insulation ring seat 27 is supported by a plurality of fixed feet 36, described fixed feet 36 is fixedly welded on lower furnace body 16 inwalls, described insulation ring seat 27 is welded and fixed with fixed feet 36, in described insulation ring seat 27 and fixed feet 36, be provided with inner sleeve, for the electric field lead-in wire 37 of controlling electric field 25 is drawn to lower furnace body 16 outsides, and be connected with sintering controller 34, described workpiece to be sintered 23, is embedded in the middle of graphite packing 22.
Described body of heater is sealed high-voltage resistant structure, its bottom is provided with gas inlet and outlet 32, described gas inlet and outlet 32 is connected with gas cylinder 29 with compressor 31 respectively, between described gas inlet and outlet 32 and compressor 31, gas cylinder 29, be provided with tensimeter 28 and air valve 30, switch or relief pressure that described air valve 30 is carried for controlling gas; In the time of in gas is passed into body of heater, body of heater inside produce high pressure, and described high pressure puts on the rubber sealing boot 26 in stove, and then pressure is put on graphite packing 22 and workpiece to be sintered 23.
Described body of heater is outside equipped with impulse current generator 33 and sintering controller 34, described contact conductor 37, electric field lead-in wire 21, thermopair 17 are all communicated with sintering controller 34, described impulse current generator 33 is drawn 37 lines with electrode and is communicated with, by 34 pairs of sintering process processes of sintering controller, control, realize two control sintering 9 that wait of stupalith base substrate.
Described ceramic sintered bodies processing, comprises the sintered compact blank demoulding 10, blank shaping 11, roughing 12, precision work 13, component polishing 14 and component finished product 15; Ceramic body two wait a control sintering oven 9 in after sintering, workpiece 23 becomes sintered compact, sintered compact is taken out from two grade a control sintering oven 9, after graphite packing 22 collection and treatments, again utilize, the sintered compact demoulding and shaping, the workpiece of sintering is carried out to roughing 12 and precision work 13 by technological standards requirement, then grind and polishing, obtain component finished product 15.
Sintering method is controlled for alumina-ceramic powder packing is entered in rubber cuff in described two field of waiting; Pack two control sintering oven that wait into, pass into protectiveness nitrogen and apply isostatic pressure, the gaseous tension applying is 15---30MPa; According to the actual requirement of material, apply pulse plasma electric current, according to temperature rise rate, be 500 ℃---700 ℃/min, the temperature parameter of controlling the field control sintering ovens such as two is 1100 ℃---1450 ℃; Adjust with control annular simultaneously and control the intensity of electric field and alternately variation, rising along with temperature in stove, the intensity of voltage stabilizing pulsed current can improve gradually, and the intensity of described control electric field also increases, guarantee peripheral electric field to the effect of base substrate inside plasma state material in significant condition; When the temperature in sintering oven reaches sintering temperature, keep temperature 10min; According to the temperature conditions in sintering oven, by increasing pulsed current, increasing peripheral control strength of electric field, or sintering oven is carried out to cooling process, control the variation of temperature in sintering process; After being incubated, close impulse current generator switch, closing control electric field switch, two control sintering oven naturally cooling or cooling by cooling sandwith layer that wait, after system cooling, release; From the field control sintering ovens such as two, take out sintered compact, carry out roughing and precision work.
The stupalith of the utility model institute sintering, bending strength or reach 700MPa; Fracture toughness property can reach 8MPam 1/2; Density can reach more than 99.5; Vickers' hardness can reach 40GPa.
This Novel operating process is: according to working specification, pack workpiece to be sintered into two grade in a control sintering oven 9, by furnace sealing and adjust parameters to original state, connect and control power supply, check whole sintering system, open gas cylinder 29, open compressor 31 and control air valve 30, exert pressure to body of heater inside, when furnace pressure reaches preset pressure, open impulse current generator 33, progressively add load electric current to power-on and power-off pole plate 19, pulsed current is by graphite packing 22nd district, and act on base substrate to be sintered, because pulsed current causes the inner plasma discharging that occurs of base substrate, and heat up rapidly, reach after sintering temperature, workpiece 23 is inner all obtains pulse current discharging effect with outside, the static pressure External Force Actings such as generation and the effect of pulsed current internal discharge, in the time of sintering, sintering controller 34 is controlled many groups electric field 25 of annular spread, workpiece 23 is applied to pulsed, the electric field action of alternation, by the impact of pulse alternating electric field 25, cause pulsed current and the electromagnetic field environment of workpiece 23 inside, the power of following external electrical field 25 changes with direction of an electric field and changes, synchronously carry out in real time multi-angle, multi-direction variation, thereby realize between workpiece 23 internal crystal frameworks, between crystal boundary, melt between body, between molten matter and solvent, between solid phase and liquid phase, between gas phase and liquid phase, there is complicated exchange and fusion, and the surface-area between ceramic particle and internal energy are fully optimized, thereby obtain high quality high performance structural stupalith.
Embodiment 1, controls the two control sintering oven that wait of electric field for uniform six; As shown in Figure 2;
Embodiment 2, control the two control sintering oven that wait of electric field for uniform four; As shown in Figure 5;
Embodiment 3, and uniform three arcs are controlled the two control sintering oven that wait of electric field; As shown in Figure 6;
The static-pressure field control discharge plasma sinterings such as this new ceramic material are the plasma states based on material itself and generating heat, be essentially different with type of heating, polarization energy mode, luminous energy mode by external heat source, plasma discharging is compared and is had obvious advantage and feature with conventional energy presentation mode, as high in efficiency, capacity usage ratio is high, pollution-free, can whole rapid heating, sintering temperature reduces, the uniform microstructure of material etc.(1) heating and sintering velocity are exceedingly fast.The traditional heating of material is that by sample conduction from outward appearance to inner essence, to reach temperature even.Therefore due to the poor thermal conductivity of most stupaliths, heating and sintered ceramic need for a long time, generally in hour, large component institute's time spent is just longer.Two sintering such as grade are that material internal integral body heats simultaneously, heat-up rate is fast, thereby greatly shortened sintering time, the sintering to some stupaliths particularly, from being reduced in several days even several weeks of past, use two several minutes magnitudes that wait sintering, thereby greatly improved the utilization ratio of production efficiency and the energy.(2) instantaneity and pollution-free.In the sintering processes such as two owing to not passing through thermal conduction, thereby there is no thermal inertia, there is instantaneity, can instantaneous break thermal source and heating in time, embodied feature energy-conservation and that be easy to control.Meanwhile, two sintering that wait can not pollute the material of institute's sintering, can be conveniently implemented in the sintering under vacuum and various atmosphere and pressure, can not look like oil firing, gas, coal etc. yet and produce obnoxious flavour contaminate environment in sintering process.(3) energy-efficient.The sintering temperatures such as two are compared with normal sintering temperature, and maximum cooling extent can reach 500 left and right; The efficiency that is generally transformed into heat energy from plasma energy can reach more than 90%, in addition twoly waits the time of sintering short, therefore can greatly reduce energy consumption.(4) selective sintering.For heterogeneous mixing material, due to the difference of different media plasma ability, the plasma intensity of generation is different, and heat effect is also different, utilizes this point to carry out selective sintering to matrix material.(5) improve microstructure and the macro property of stupalith.Because the speed of two sintering such as grade is fast, the time is short, thereby avoid the abnormal growth of crystal grain in sintering process, finally can obtain the superfine crystal particle structural ceramic material with high strength and toughness.(6) moulding and sintering can be realized a step and complete, the regulation and control of gas-static and external electric field and plasma agglomeration combine, and make the moulding of ceramic structure material and sintering can realize a step and complete, and have improved efficiency, saved cost, closed product performance and obtain tremendous increase.(7) this novel moulding that makes stupalith is shortened process time and cycle with a sintering, thereby output in enormous quantities, raise labour efficiency, and increase enterprise competitiveness.
Above-mentioned explanation to the disclosed embodiments, makes professional and technical personnel in the field can realize or use the utility model.To the multiple modification of these embodiment, will be apparent for those skilled in the art, General Principle as defined herein can, in the situation that not departing from spirit or scope of the present utility model, realize in other embodiments.Therefore, the utility model will can not be restricted to these embodiment shown in this article, but will meet the widest scope consistent with principle disclosed herein and features of novelty.

Claims (3)

1. a stupalith sintering oven, it is characterized in that, comprise lower furnace body, thermopair, upper furnace body, battery lead plate, bench insulator, contact conductor, graphite packing, workpiece, cooling water outlet, control electric field, rubber sealing boot, insulation ring seat, tensimeter, gas cylinder, air valve, compressor, gas inlet and outlet, impulse current generator, sintering controller, cold water inlet, fixed feet, electric field lead-in wire and tongued and grooved flanges; Described upper furnace body and lower furnace body form a control sintering body of heater such as two by tongued and grooved flanges, and described body of heater is provided with cooling water sandwich and water coolant gangway; Described upper furnace body side is provided with thermocouple probe, and described body of heater inner top and bottom are respectively arranged with bench insulator, on described bench insulator, are provided with battery lead plate, and described battery lead plate is connected with body of heater external pulse current generator by contact conductor; Described battery lead plate is upper and lower two, between described upper and lower two electrode plate, be provided with rubber sealing boot, in described rubber sealing boot, be filled with graphite packing, the effect of fixing internal workpiece and On current is played in described graphite packing, and described graphite packing center is mounted with workpiece to be sintered.
2. a kind of stupalith sintering oven according to claim 1, it is characterized in that, described lower furnace body inside is provided with a plurality of control electric fields, described control electric field is flat structure, polylith is controlled the even annular of electric field and is arranged in body of heater middle part, described control electric field is by the dead ring seat supports of its bottom, described insulation ring seat is supported by a plurality of fixed feet, described fixed feet is fixedly welded on inboard wall of furnace body, described insulation ring seat and fixed feet are welded and fixed, in described insulation ring seat and fixed feet, be provided with inner sleeve, for the electric field of controlling electric field being drawn to body of heater outside, and be connected with sintering controller, described workpiece, is embedded in the middle of graphite packing.
3. a kind of stupalith sintering oven according to claim 1, it is characterized in that, described body of heater is sealed high-voltage resistant structure, its bottom is provided with gas inlet and outlet, described gas inlet and outlet, be connected with gas cylinder with compressor respectively, between described gas inlet and outlet and compressor, gas cylinder, be provided with tensimeter and air valve.
CN201420019268.5U 2014-01-14 2014-01-14 A kind of stupalith sintering oven Withdrawn - After Issue CN203938607U (en)

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CN103819202A (en) * 2014-01-14 2014-05-28 苏州永佳超硬耐磨材料有限公司 Ceramic material sintering furnace and isostatic pressing field-controlled spark pulse sintering method
CN105135873A (en) * 2015-08-05 2015-12-09 清华大学 Dynamic pressure electric pulse double-field control sintering furnace and sintering method
CN106714359A (en) * 2017-01-13 2017-05-24 盖健楠 Directional solidification ceramic sintering device and method based on discharge plasma
CN110650837A (en) * 2017-05-31 2020-01-03 昆特斯技术公司 Pressing equipment
CN113566559A (en) * 2021-08-05 2021-10-29 成都凯天电子股份有限公司 Sintering device for preparing low-temperature sintered piezoelectric ceramics

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103819202A (en) * 2014-01-14 2014-05-28 苏州永佳超硬耐磨材料有限公司 Ceramic material sintering furnace and isostatic pressing field-controlled spark pulse sintering method
CN103819202B (en) * 2014-01-14 2015-12-02 苏州永佳超硬耐磨材料有限公司 A kind of stupalith sintering oven and isostatic pressed field control plasma agglomeration method
CN105135873A (en) * 2015-08-05 2015-12-09 清华大学 Dynamic pressure electric pulse double-field control sintering furnace and sintering method
CN106714359A (en) * 2017-01-13 2017-05-24 盖健楠 Directional solidification ceramic sintering device and method based on discharge plasma
CN110650837A (en) * 2017-05-31 2020-01-03 昆特斯技术公司 Pressing equipment
CN110650837B (en) * 2017-05-31 2021-11-30 昆特斯技术公司 Pressing equipment
US11780192B2 (en) 2017-05-31 2023-10-10 Quintus Technologies Ab Pressing arrangement
CN113566559A (en) * 2021-08-05 2021-10-29 成都凯天电子股份有限公司 Sintering device for preparing low-temperature sintered piezoelectric ceramics
WO2023010769A1 (en) * 2021-08-05 2023-02-09 成都凯天电子股份有限公司 Sintering device for use in preparation of low-temperature sintered piezoelectric ceramics
CN113566559B (en) * 2021-08-05 2023-02-28 成都凯天电子股份有限公司 Sintering device for preparing low-temperature sintered piezoelectric ceramics

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