CN210807712U

CN210807712U - High-voltage composite electrode pressure head structure for flash sintering

Info

Publication number: CN210807712U
Application number: CN201921526854.8U
Authority: CN
Inventors: 马付根; 江南; 宋茜茜
Original assignee: Anhui Chenxinwei Industrial Technology Co ltd; Ningbo Chenxin Vac Industrial Technology Co ltd
Current assignee: Anhui Chenxinwei Industrial Technology Co ltd; Ningbo Chenxin Vac Industrial Technology Co ltd
Priority date: 2019-09-12
Filing date: 2019-09-12
Publication date: 2020-06-19
Anticipated expiration: 2029-09-12

Abstract

The utility model relates to a flash sintering is with high-pressure composite electrode pressure head structure, in particular to flash sintering equipment field, including the pressure head body that has the inner chamber, wear to locate this internal wire electrode of pressure head and set up and be used for with the one end of pressing the material contact and with wire electrode fixed connection's electrode slice in the pressure head body, the outer wall cover that the wire electrode is located one section of pressure head body inner chamber is equipped with insulation support, be provided with the insulator between electrode slice and this tip of pressure head, wire electrode one end is passed pressure head body one end and insulation support and electrode slice fixed connection, and the wire electrode other end passes the pressure head body other end and is connected with the power. The utility model discloses not only can be integrated as a whole with electrode and pressure head, carry out effectual insulation protection to the electrode moreover, avoided voltage loss, guaranteed that the electrode possesses high temperature, high pressure, insulation protection's performance, satisfy flash sintering equipment to fine grain ceramic material's preparation requirement.

Description

High-voltage composite electrode pressure head structure for flash sintering

Technical Field

The utility model belongs to the technical field of flash sintering equipment and specifically relates to a flash sintering is with high-pressure composite electrode pressure head structure is related to.

Background

The fine-grained ceramic material has many advantages, and is a focus of research and development in recent years, and especially, the nano-ceramic material with the grain size below 100 nm has characteristics which are not possessed by the traditional ceramic, such as change of heat conductivity and electric conductivity, special melting point, mechanical properties, especially improvement of toughness and the like. The growth of crystal grains occurs in the ceramic sintering process, the high temperature provided by sintering and other driving forces such as atmosphere, pressure, electric field and the like promote the crystal grains to grow continuously in the process, and the inhibition of the growth of the crystal grains in the ceramic densification process becomes the key point of the research on the fine-grained ceramics.

Research has shown that sintering time is critical to control grain growth, providing sufficient driving force. The extremely short sintering time can better control the size of crystal grains, but in order to ensure high compactness of the ceramic at the same time, the instantaneous high driving force provided by sintering becomes the core technical requirement. To achieve this, researchers have changed the traditional sintering process, through atmosphere sintering and pressure-assisted sintering, and although the sintering time is reduced, the ability to control the grains is far from sufficient to meet the market demand. Spark Plasma Sintering (SPS) is a novel electric field assisted sintering mode, and combines ion activation, hot pressing and resistance heating, so that the sintering time can be greatly reduced (the sintering time is reduced to 1-5 minutes), and the grain growth is inhibited; however, SPS has a certain requirement for the conductivity of the material powder, so that it has a limited application in insulating ceramic materials. Different from a large-current small-voltage discharge mode of discharge plasma sintering, a novel large-voltage-assisted flash sintering mode is produced, and becomes a leading-edge hot topic of current international ceramic preparation. The flash sintering mode is that a strong driving force is generated by an electron avalanche effect formed by the high voltage breakdown of the insulating ceramic powder, and the nucleation incubation period is greatly shortened by combining the assistance of pressure and temperature, and finally, the ceramic sintering technology with high density and controllable crystal grains is realized within seconds. Electrodes are important components of flash sintering equipment (i.e., sintering equipment employing flash sintering processes) and have very stringent requirements for their preparation.

The Chinese patent application with the publication number of CN101505557A in the prior art discloses a composite electrode pressure head, which is made by compounding pressure heads with different conductive performances and electrodes, wherein the electrodes are completely covered in the pressure heads, and the conductive performances of the electrodes are superior to those of the pressure heads.

By adopting the composite pressure head structure, although the pressure head can be utilized to completely coat the electrode, the electrode and the pressure head are integrated, and the conductive performance of the electrode is superior to that of the pressure head, so that most of current reaches the die through the electrode, the heat loss of the pressure head is reduced, and the problem that the pressure head is easy to damage due to overheating is avoided; however, since the insulation protection structure is not arranged between the electrode and the pressure head, the conductivity of the electrode cannot be effectively ensured, a part of voltage is lost through the pressure head all the time, the high-voltage performance of the electrode is reduced, and the sintering quality is affected. Even if the electrode and the pressure head are made of different conductive materials, the voltage loss is only reduced, the defect that the high-voltage performance of the electrode is reduced due to the voltage loss cannot be avoided, the requirement that the electrode needs high voltage and insulation protection in flash sintering cannot be met, and the difficulty in preparing the fine-grain ceramic material by flash sintering equipment is increased.

SUMMERY OF THE UTILITY MODEL

The utility model aims at providing a flash is high-pressure composite electrode pressure head structure for sintering not only can be integrated as a whole with electrode and pressure head, has carried out effectual insulation protection to the electrode moreover, has avoided voltage loss, has guaranteed that the electrode possesses high temperature, high pressure, insulation protection's performance, satisfies flash sintering equipment to fine grain ceramic material's preparation requirement.

The above utility model discloses an above-mentioned utility model purpose can realize through following technical scheme:

the utility model provides a flash is high-pressure composite electrode pressure head structure for sintering, including the pressure head body that has the inner chamber, wear to locate this internal wire electrode of pressure head and set up and be used for pressing the one end of material contact and with wire electrode fixed connection's electrode slice in the pressure head body, the outer wall cover that the wire electrode is located one section of pressure head body inner chamber is equipped with insulation support, be provided with the insulator between electrode slice and this end of the body of pressure head, wire electrode one end is passed pressure head body one end and insulation support and electrode slice fixed connection, and the wire electrode other end passes the pressure head body other end and is connected with the power.

By adopting the technical scheme, the pressure head body, the electrode wire and the electrode plate are integrated into a whole, so that the electrode wire can be protected by the pressure head body, the integral supporting strength is improved, and the service life of the electrode wire is prolonged; meanwhile, by arranging the insulating sleeve and the insulating base, the voltage of the electrode wire and the electrode plate can be completely prevented from flowing away through the pressure head body, the electrode is guaranteed to have high-temperature, high-voltage and insulating protection performances, and the preparation requirement of flash sintering equipment on fine-grained ceramic materials is met.

Furthermore, the pressure head body includes that inside is equipped with the depression bar that leads to the chamber along the axial and is fixed in pressure head seat and the shrouding at depression bar both ends respectively, the chamber that leads to of depression bar encloses the inner chamber that forms the pressure head body jointly with pressure head seat and shrouding.

By adopting the technical scheme, the electrode wire is convenient to install, and the pressure head body is convenient to carry out thermal protection.

Furthermore, the electrode wire axially penetrates through the through cavity of the pressing rod, and the pressing head seat, the pressing rod, the electrode wire, the insulating sleeve, the sealing plate, the insulating seat and the electrode plate are coaxially arranged.

Through adopting above-mentioned technical scheme, guarantee overall structure's uniformity, the assembly of being convenient for promotes performance.

Furthermore, the insulating seat is fixed on the end face of the sealing plate, and the electrode plate is fixed on the end face of the insulating seat through a high-temperature-resistant fastener I.

By adopting the technical scheme, the insulation protection between the electrode plate and the sealing plate is realized, the voltage of the electrode plate is prevented from being lost through the pressure head body, and the electrode plate is ensured to have high-temperature and high-voltage performance; meanwhile, the high-temperature-resistant fasteners I are adopted for connection and fixation, so that the high-temperature-resistant performance can be improved, the connection strength can be ensured, and the mounting, the dismounting and the replacement are convenient.

Further, the shrouding center is equipped with the via hole that supplies the wire electrode to pass through, pressure headstock center is equipped with the axial shoulder hole that supplies the wire electrode to pass through, insulating tube one end is passed the via hole butt in insulating seat terminal surface, and the other end inserts in the axial shoulder hole to the butt is equipped with on being used for carrying out the seal assembly sealed to axial shoulder hole and wire electrode on the pressure headstock.

By adopting the technical scheme, the insulation sleeve is fixed, the insulation sleeve is used for isolating the electrode wire from the inner cavity of the pressure head body, the insulation protection performance is improved, the voltage of the electrode wire is prevented from being lost through the pressure head body, and the electrode wire is ensured to have high-temperature and high-voltage performance; meanwhile, the sealing assembly is arranged to seal the axial stepped hole and the electrode wire.

Furthermore, one end of the axial stepped hole, which is close to the pressure rod, is a small-diameter section, one end of the axial stepped hole, which is far away from the pressure rod, is a large-diameter section, the sealing assembly is located at one end of the pressure head seat, which is close to the large-diameter section of the axial stepped hole, and the sealing assembly is sleeved outside the electrode wire.

By adopting the technical scheme, the axial stepped hole and the electrode wire are sealed, and the sealing performance is ensured.

Further, seal assembly is including annular seal receptacle I and annular seal receptacle II of coaxial setting, the longitudinal section of annular seal receptacle I and annular seal receptacle II is T shape structure, and the vertical section of annular seal receptacle I inserts in the major diameter section of axial shoulder hole, and the vertical section terminal surface and the insulating tube terminal surface butt of annular seal receptacle I, the vertical section of annular seal receptacle II inserts in the annular mounting groove that the horizontal segment center of annular seal receptacle I was equipped with, the horizontal segment of annular seal receptacle I and annular seal receptacle II is fixed in the pressure head seat terminal surface through high temperature resistant fastener II.

By adopting the technical scheme, the sealing structure formed by the double annular sealing seats can improve the sealing effect, so that the inner cavity of the pressure head body can form a vacuum cavity, the insulating sleeve can be compressed and positioned, and the structure is reasonable; meanwhile, the high-temperature-resistant fasteners II are adopted for connection and fixation, so that the high-temperature-resistant performance can be improved, the connection strength can be ensured, and the mounting, the dismounting and the replacement are convenient.

Further, a gap space is reserved between the end face of the II vertical sections of the annular sealing seats and the bottom of the annular mounting groove, a sealing ring used for sealing the electrode wire is arranged in the gap space, the inner wall of the sealing ring is abutted to the outer wall of the electrode wire, the outer wall of the sealing ring is abutted to the side wall of the annular mounting groove, gaskets are arranged between the end faces of the two ends of the sealing ring and the end faces of the II vertical sections of the annular sealing seats and the bottom of the annular mounting groove respectively, and the electrode wire is sleeved with the gaskets.

Through adopting above-mentioned technical scheme, can utilize sealing washer and gasket, realize sealing and the location to the wire electrode to promote sealed effect.

Further, a liquid inlet channel and a liquid outlet channel which are communicated with the pressure rod through cavity are respectively arranged on two sides of the pressure head seat along the radial direction, the inlet end of the liquid inlet channel is connected with a liquid inlet joint, the outlet end of the liquid inlet channel is fixedly provided with a liquid inlet pipe which extends into the pressure rod through cavity along the axial direction, and the outlet end of the liquid outlet channel is connected with a liquid outlet joint; the insulating sleeve is sleeved with a liquid-isolating sleeve for preventing liquid from entering the insulating sleeve, and two ends of the liquid-isolating sleeve are respectively and hermetically fixed on the pressure head seat and the sealing plate.

By adopting the technical scheme, the liquid inlet channel, the liquid inlet pipe and the liquid outlet channel can be utilized to introduce cooling liquid into the pressure head body, so that the thermal protection of the pressure head body is realized, and the service life of the pressure head body is prolonged; through setting up liquid separation sleeve pipe to it is intraductal to completely cut off coolant liquid entering insulation sleeve, guarantees insulation sleeve's normal use.

Furthermore, the surface of the pressure lever is coated with an insulating coating, and a furnace chamber insulating sealing seat which is used for being in sealing connection with a furnace chamber of the flash sintering equipment is sleeved outside the pressure lever.

Through adopting above-mentioned technical scheme to guarantee the insulation protection performance of depression bar, promote holistic performance.

To sum up, the utility model discloses a beneficial technological effect does:

1. the pressure head body, the electrode wire and the electrode plate are integrated into a whole, so that the electrode wire can be protected through the pressure head body, the integral supporting strength is improved, and the service life of the electrode wire is prolonged;

2. by arranging the insulating sleeve and the insulating seat, the voltage of the electrode wire and the electrode plate can be completely prevented from losing through the pressure head body, the electrode is ensured to have the performances of high temperature, high voltage and insulating protection, and the preparation requirement of flash sintering equipment on fine-grain ceramic materials is met;

3. by arranging the double annular sealing seats, the sealing effect can be improved, the inner cavity of the pressure head body can form a vacuum cavity, the insulating sleeve can be compressed and positioned, and the structure is reasonable;

4. by arranging the liquid inlet channel, the liquid inlet pipe and the liquid outlet channel, cooling liquid can be introduced into the pressure head body, so that the thermal protection on the pressure head body is realized, and the service life of the pressure head body is prolonged; meanwhile, the liquid isolating sleeve is arranged to isolate cooling liquid from entering the insulating sleeve, and normal use of the insulating sleeve is guaranteed.

Drawings

Fig. 1 is a schematic view of the overall structure of the upper pressure head body of the present invention;

FIG. 2 is a cross-sectional view taken along line A-A of FIG. 1;

FIG. 3 is an enlarged schematic view of portion B of FIG. 2;

FIG. 4 is a schematic view of the installation structure of the flash sintering apparatus of the present invention;

fig. 5 is a micro-topography of a ceramic material prepared using a flash sintering apparatus according to the present invention.

In the figure, 1, a wire electrode; 2. an electrode sheet; 3. an insulating sleeve; 4. an insulating base; 5. a pressure lever; 5a, passing through the cavity; 6. a press head seat; 6a, an axial stepped hole; 6b, a liquid inlet channel; 6c, a liquid outlet channel; 7. closing the plate; 7a, a via hole; 8. an upper ram body; 9. a lower pressure head body; 10. an annular sealing seat I; 11. an annular seal seat II; 12. an insulating sealing seat of the furnace chamber; 13. a seal ring; 14. a gasket; 15. a liquid inlet joint; 16. a liquid inlet pipe; 17. a liquid outlet joint; 18. a liquid-proof sleeve.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings.

Referring to fig. 1 and 2, the utility model discloses a high-pressure composite electrode pressure head structure for flash sintering, including the pressure head body that has the inner chamber, wear to locate electrode silk 1 in the pressure head body and be fixed in the pressure head body and be used for with the one end of pressing the material contact and with electrode silk 1 fixed connection's electrode slice 2, the tip of electrode silk 1 has the connector of outband screw thread in this embodiment, open on the electrode slice 2 with the screw hole of connector screw-thread fit, electrode silk 1 is through the connector with the screw hole threaded connection on the electrode slice, the installation of being convenient for; the electrode wire is made of platinum, niobium or copper, the electrode plate 2 is made of tungsten, molybdenum, tantalum, niobium, chromium or zirconium, the electrode wire 1 is made of platinum materials, and the electrode plate 2 is made of tungsten materials, so that a composite electrode structure is realized, and the conductivity is improved; the electrode slice 2 is used for contacting with the pressing material, and the area of the electrode slice is larger than or equal to the pressing area. The outer wall cover that electrode silk 1 is located one section in the pressure head body inner chamber is equipped with insulation support 3, and is concrete, adopts clearance fit between insulation support 3 and the electrode silk 1, and insulation support 3 internal diameter is greater than 1 diameter of electrode silk. Be fixed with insulator seat 4 between electrode slice 2 and the pressure head body tip, 1 one end of wire electrode passes pressure head body one end and insulator seat 4 and electrode slice 2 fixed connection, the 1 other end of wire electrode passes the pressure head body other end and is connected with power (not shown in the figure), the power adopts direct current high voltage power supply in this embodiment, in order to provide plus high voltage electric field, exert direct current pulse voltage between powder granule and obtain powerful drive power in the puncture in the twinkling of an eye and improve the powder density, and greatly shorten the sintering time, realize second level sintering process, effective control ceramic grain obtains fine grain ceramic material. In this embodiment, the insulating sleeve 3 is made of alumina, nylon, polytetrafluoroethylene, or polyphenylene sulfide, and the insulating base 4 is made of boron nitride, alumina, yttria, beryllia, or magnesia, wherein the insulating sleeve 3 is made of an alumina material, and the insulating base 4 is made of a boron nitride material, so as to ensure insulating performance.

Referring to fig. 2 and 4, the pressure head body includes a pressure rod 5 having a through cavity 5a along an axial direction inside, and a pressure head seat 6 and a sealing plate 7 welded and fixed to two ends of the pressure rod 5, wherein the through cavity 5a of the pressure rod 5, the pressure head seat 6 and the sealing plate 7 together enclose an inner cavity of the pressure head body. The pressure head body is including last pressure head body 8 and the lower pressure head body 9 of mutually supporting in this embodiment, it is the same with the component part of lower pressure head body 9 to go up pressure head body 8, the difference only lies in that the depression bar length of lower pressure head body 9 is greater than the depression bar length of last pressure head body 8, wherein go up pressure head body 8 be used for with the furnace frame fixed connection of flash sintering equipment, lower pressure head body 9 is used for being connected with flash sintering equipment's hydro-cylinder, during the use, it is motionless to go up pressure head body 8, lower pressure head body 9 can move along vertical direction under the drive of hydro-cylinder. In the embodiment, the pressure rod 5, the pressure head seat 6 and the sealing plate 7 are all made of stainless steel materials, so that the heat resistance is good, and the processing and the manufacturing are convenient.

Referring to fig. 2 and 3, the wire electrode 1 axially penetrates through the through cavity 5a of the press rod 5, the press head seat 6, the press rod 5, the wire electrode 1, the insulating sleeve 3, the sealing plate 7, the insulating seat 4 and the electrode plate 2 are coaxially arranged, the cross sections of the press head seat 6, the press rod 5, the wire electrode 1, the insulating sleeve 3, the sealing plate 7, the insulating seat 4 and the electrode plate 2 are all circular in the embodiment, and the diameters of the press rod 5, the sealing plate 7, the insulating seat 4 and the electrode plate 2 are the same so as to improve the integrity after assembly. Insulating seat 4 is fixed in 7 terminal surfaces of shrouding, and electrode slice 2 is fixed in 4 terminal surfaces of insulating seat through high temperature resistant fastener I (not shown in the figure), and insulating seat 4 is fixed in 7 terminal surfaces of shrouding through high temperature resistant fastener III in this embodiment, and high temperature resistant fastener I and high temperature resistant fastener III can be tungsten bolt or molybdenum bolt or tantalum bolt, and high temperature resistant fastener I and high temperature resistant fastener III of this embodiment are the tungsten bolt. 7 centers of shrouding are equipped with the via hole 7a that supplies 1 electrode wire to pass through, 6 centers of pressure head seat are equipped with the axial shoulder hole 6a that supplies 1 electrode wire to pass through, via hole 7a butt is passed to 3 one end of insulating sleeve in 4 terminal surfaces of insulating seat, the other end inserts in axial shoulder hole 6a, and the butt is equipped with on pressure head seat 6 and is used for carrying out the seal assembly sealed to axial shoulder hole 6a and electrode wire 1, specifically, the one end that axial shoulder hole 6a is close to depression bar 5 is the path section, the one end of keeping away from depression bar 5 is the major diameter section, seal assembly is located the one end that pressure head seat 6 is close to the major diameter section of axial shoulder hole 6a, and seal assembly cover is located outside the electrode wire 1. A through hole for the electrode wire 1 to pass through is formed in the center of the insulating seat 4 in the embodiment, one end of the electrode wire 1 sequentially passes through the through hole 7a and the through hole and then is fixed with the electrode plate 2, and the other end of the electrode wire 1 passes through the axial stepped hole 6a and then is connected with a power supply; the one end terminal surface center that shrouding 7 is used for being connected with insulator seat 4 has recess I, and insulator seat 4 is used for having the one end terminal surface center of being connected with shrouding 7 with I complex boss I of recess, and insulator seat 4 is used for having recess II with the one end terminal surface center that electrode slice 2 is connected, and electrode slice 2 is used for having the one end terminal surface center of being connected with insulator seat 4 with II complex bosses II of recess, and the junction adopts unsmooth complex mode, is convenient for fix a position and assemble.

Referring to fig. 3, seal assembly includes annular seal receptacle I10 and annular seal receptacle II 11 of coaxial setting, the longitudinal section of annular seal receptacle I10 and annular seal receptacle II 11 is T shape structure, the vertical section of annular seal receptacle I10 inserts in the major diameter section of axial shoulder hole 6a, and the vertical section terminal surface of annular seal receptacle I10 and 3 terminal surface butts of insulating sleeve, the vertical section of annular seal receptacle II 11 inserts in the annular mounting groove that the horizontal section center of annular seal receptacle I10 was equipped with, the horizontal section of annular seal receptacle I10 and annular seal receptacle II 11 is fixed in pressure head seat 6 terminal surface through resistant high temperature fastener II (not shown in the figure). In the embodiment, the annular sealing seat I10 and the annular sealing seat II 11 are in clearance fit with the electrode wire 1, and the inner diameters of the annular sealing seat I10 and the annular sealing seat II 11 are larger than the diameter of the electrode wire 1; the vertical section of the annular sealing seat II 11 is in clearance fit with the annular mounting groove of the annular sealing seat I10, and the caliber of the annular mounting groove is equal to the outer diameter of the vertical section of the annular sealing seat II 11; the annular sealing seat I10 and the annular sealing seat II 11 are both made of insulating materials; a slot is formed in the center of one end, used for abutting against the insulating sleeve 3, of the annular sealing seat I10, and one end of the insulating sleeve 3 is inserted into and abutted against the slot; high temperature resistant fastener II is the tungsten bolt, set up the hole that supplies high temperature resistant fastener II to pass on annular seal receptacle I10 and the annular seal receptacle II 11 respectively, press headstock 6 terminal surface set up with II complex screw holes of high temperature resistant fastener, high temperature resistant fastener II pass in proper order on annular seal receptacle I10 and the annular seal receptacle II 11 behind the hole with the screw hole threaded connection of press headstock 6 terminal surface, realize that annular seal receptacle I10 and annular seal receptacle II 11 are fixed with being connected between the press headstock 6. Specifically, leave the clearance space between II 11 vertical section terminal surfaces of annular seal seat and the annular mounting groove tank bottom, install in this clearance space and be used for 1 sealed sealing washer 13 to the wire electrode, 13 inner wall butts of sealing washer are in 1 outer wall of wire electrode, 13 outer wall butts of sealing washer are in annular mounting groove lateral wall, install gasket 14 between 13 both ends terminal surfaces of sealing washer and II 11 vertical section terminal surfaces of annular seal seat and the annular mounting groove tank bottom respectively, 14 covers of gasket are located outside the wire electrode 1, during the installation, it is sealed to extrude sealing washer 13 through the gasket 14 that is located 13 both ends terminal surfaces and warp, with promote sealed effect, fix a position wire electrode 1 simultaneously. In this embodiment, the pad 14 is in clearance fit with the wire electrode 1, and the inner diameter of the pad 14 is larger than the diameter of the wire electrode 1.

Referring to fig. 2 and 3, a liquid inlet channel 6b and a liquid outlet channel 6c which are communicated with the through cavity 5a of the pressure lever are respectively arranged at two sides of the pressure head seat 6 along the radial direction, a liquid inlet joint 15 is connected with an inlet end of the liquid inlet channel 6b, a liquid inlet pipe 16 which axially extends into the through cavity 5a of the pressure lever is fixed at an outlet end of the liquid inlet channel 6b, and a liquid outlet joint 17 is connected with an outlet end of the liquid outlet channel 6c, wherein the liquid inlet joint 15 and the liquid outlet joint 17 are respectively in threaded connection with the liquid inlet channel 6b and the liquid outlet channel; the insulating sleeve 3 overcoat is equipped with liquid-proof sleeve 18 that is used for preventing liquid to get into insulating sleeve 3, and liquid-proof sleeve 18 both ends are sealed respectively and are fixed in on pressure head seat 6 and shrouding 7, and in this embodiment liquid-proof sleeve 18 one end welded seal is fixed in via hole 7a, and other end welded seal is fixed in the path section of axial shoulder hole 6a, and liquid-proof sleeve 18 adopts stainless steel material to make.

Referring to fig. 4, the surface of the compression bar 5 is coated with an insulating coating, a furnace chamber insulating sealing seat 12 for sealing connection with a furnace chamber of the flash sintering equipment is sleeved outside the compression bar 5, and in this embodiment, the insulating coating and the furnace chamber insulating sealing seat 12 are both made of alumina.

The above embodiments are applied to flash sintering equipment to prepare ceramic materials:

the pressure head seat of the upper pressure head body is fixed on a furnace frame of the flash sintering equipment, the pressure head seat of the lower pressure head body is connected with an oil cylinder through a connecting frame, and the pressure rods of the upper pressure head body and the lower pressure head body are respectively sealed with a furnace cavity of the flash sintering equipment through furnace cavity insulating sealing seats. Pressing materials into zirconia ceramic powder, placing the zirconia ceramic powder into a sintering mould of flash sintering equipment, preserving heat for one hour at 1300 ℃, then carrying out flash firing at the voltage of 1KV for 5 seconds, and sintering to obtain the high-density and fine-grain zirconia ceramic, wherein referring to fig. 5, the density reaches 99.99%, and the average grain size is 0.7 μm. Therefore, the utility model can realize the sintering condition requirements of DC power supply voltage of 0-1500V, temperature of 0-2000 ℃ and pressure of 0-500 MPa, and meet the preparation conditions of various ceramic materials; the method is energy-saving and environment-friendly, and compared with the conventional hot-pressing sintering technology, the sintering temperature for firing products with the same quality can be reduced by more than 300 ℃; the utility model can be applied to the preparation of different ceramic system materials by adjusting the value of the applied voltage and combining the pressure and the temperature.

The embodiment of this specific implementation mode is the preferred embodiment of the present invention, not limit according to this the utility model discloses a protection scope, so: all equivalent changes made according to the structure, shape and principle of the utility model are covered within the protection scope of the utility model.

Claims

1. The utility model provides a flash sintering is with high-pressure composite electrode pressure head structure which characterized in that: including the pressure head body that has the inner chamber, wear to locate this internal wire electrode (1) of pressure head and set up in the pressure head body be used for with press the material contact one end and with wire electrode (1) fixed connection's electrode slice (2), wire electrode (1) is located one section outer wall cover in pressure head body inner chamber and is equipped with insulation support (3), be provided with between electrode slice (2) and the pressure head body tip insulating seat (4), wire electrode (1) one end is passed pressure head body one end and insulating seat (4) and electrode slice (2) fixed connection, and the wire electrode (1) other end passes the pressure head body other end and is connected with the power.

2. The high-voltage composite electrode pressure head structure for flash sintering according to claim 1, wherein: the pressure head body comprises a pressure rod (5) which is internally provided with a through cavity (5 a) along the axial direction, and a pressure head seat (6) and a sealing plate (7) which are respectively fixed at two ends of the pressure rod (5), wherein the through cavity (5 a) of the pressure rod (5) and the pressure head seat (6) and the sealing plate (7) jointly enclose an inner cavity which forms the pressure head body.

3. The high-voltage composite electrode pressure head structure for flash sintering according to claim 2, wherein: the electrode wire (1) axially penetrates through a through cavity (5 a) of the pressing rod (5), and the pressing head seat (6), the pressing rod (5), the electrode wire (1), the insulating sleeve (3), the sealing plate (7), the insulating seat (4) and the electrode plate (2) are coaxially arranged.

4. The high-voltage composite electrode pressure head structure for flash sintering according to claim 3, wherein: the insulating seat (4) is fixed on the end face of the sealing plate (7), and the electrode plate (2) is fixed on the end face of the insulating seat (4) through a high-temperature-resistant fastener I.

5. The high-voltage composite electrode pressure head structure for flash sintering according to claim 4, wherein: shrouding (7) center is equipped with via hole (7a) that supply wire electrode (1) to pass through, gland seat (6) center is equipped with axial shoulder hole (6a) that supply wire electrode (1) to pass through, via hole (7a) butt is passed to insulating sleeve (3) one end in insulating seat (4) terminal surface, and the other end inserts in axial shoulder hole (6a) to the butt is equipped with on gland seat (6) and is used for carrying out sealed seal assembly to axial shoulder hole (6a) and wire electrode (1).

6. The high-voltage composite electrode pressure head structure for flash sintering according to claim 5, wherein: one end of the axial stepped hole (6a) close to the pressure rod (5) is a small-diameter section, one end of the axial stepped hole (6a) far away from the pressure rod (5) is a large-diameter section, the sealing assembly is located at one end of the pressure head seat (6) close to the large-diameter section of the axial stepped hole (6a), and the sealing assembly is sleeved outside the electrode wire (1).

7. The high-voltage composite electrode pressure head structure for flash sintering according to claim 6, wherein: seal assembly is including annular seal receptacle I (10) and annular seal receptacle II (11) of coaxial setting, the longitudinal section of annular seal receptacle I (10) and annular seal receptacle II (11) is T shape structure, the vertical section of annular seal receptacle I (10) inserts in the big footpath section of axial shoulder hole (6a), and the vertical section terminal surface and insulating sleeve (3) terminal surface butt of annular seal receptacle I (10), the vertical section of annular seal receptacle II (11) inserts in the annular mounting groove that the horizontal segment center of annular seal receptacle I (10) was equipped with, the horizontal segment of annular seal receptacle I (10) and annular seal receptacle II (11) is fixed in pressure head seat (6) terminal surface through high temperature resistant fastener II.

8. The high-voltage composite electrode pressure head structure for flash sintering according to claim 7, wherein: leave clearance space between II (11) vertical section terminal surfaces of annular seal seat and the annular mounting groove tank bottom, be provided with in this clearance space and be used for sealing washer (13) to wire electrode (1), sealing washer (13) inner wall butt in wire electrode (1) outer wall, sealing washer (13) outer wall butt in annular mounting groove lateral wall, be provided with gasket (14) between sealing washer (13) both ends terminal surface and II (11) vertical section terminal surfaces of annular seal seat and the annular mounting groove tank bottom respectively, outside wire electrode (1) was located to gasket (14) cover.

9. The high-voltage composite electrode pressure head structure for flash sintering according to claim 2, wherein: a liquid inlet channel (6b) and a liquid outlet channel (6c) which are communicated with the compression bar through cavity (5 a) are respectively arranged at two sides of the compression bar seat (6) along the radial direction, a liquid inlet joint (15) is connected with the inlet end of the liquid inlet channel (6b), a liquid inlet pipe (16) which axially extends into the compression bar through cavity (5 a) is fixed at the outlet end of the liquid inlet channel (6b), and a liquid outlet joint (17) is connected with the outlet end of the liquid outlet channel (6 c); and a liquid-isolating sleeve (18) used for preventing liquid from entering the insulating sleeve (3) is sleeved outside the insulating sleeve (3), and two ends of the liquid-isolating sleeve (18) are respectively and hermetically fixed on the pressure head seat (6) and the sealing plate (7).

10. The high-voltage composite electrode pressure head structure for flash sintering according to claim 2, wherein: the surface of the pressure lever (5) is coated with an insulating coating, and a furnace chamber insulating sealing seat (12) which is used for being in sealing connection with a furnace chamber of the flash sintering equipment is sleeved outside the pressure lever (5).