CN216205255U

CN216205255U - Ultrafast heating sintering device and ultrafast intensification reation kettle

Info

Publication number: CN216205255U
Application number: CN202122655653.1U
Authority: CN
Inventors: 王立国
Original assignee: Shenzhen Guoxin Materials Technology Co ltd
Current assignee: Shenzhen Guoxin Materials Technology Co ltd
Priority date: 2020-11-26
Filing date: 2021-11-02
Publication date: 2022-04-05
Anticipated expiration: 2031-11-02
Also published as: CN112460996A

Abstract

The utility model discloses an ultrafast heating sintering device and an ultrafast heating reaction kettle, which can be used for ultrafast sintering, welding, smelting, reacting and the like of materials. The device includes: the electric insulation heating cavity is arranged on an electrode plate in the electric insulation heating cavity, and a power supply is electrically connected with the electrode plate; high-melting-point conductive powder is filled in the electric insulation heating cavity and is electrically connected with the electrode slice; and the pressing device is in stress contact with the high-melting-point conductive powder in the electric insulation heating cavity. The electrode plate needs to be inserted into a heating cavity filled with conductive powder, and the current of the conductive powder in the heating cavity is supplied by the electrode plate connected with a power supply, so that the workpiece is heated at an ultra-fast speed. The device has the advantages of simple structure, strong function, good controllability, low cost, suitability for industrial production and the like, and can be efficiently applied to the aspects of material sintering, welding, smelting, chemical reaction and the like.

Description

Ultrafast heating sintering device and ultrafast intensification reation kettle

Technical Field

The utility model belongs to the field of material thermal equipment, and particularly relates to an ultrafast heating sintering device and an ultrafast heating reaction kettle.

Background

The traditional heating device is difficult to generate a large-area high-temperature environment in a short time due to the limitation of a heating mode. With the rapid development of material science, many materials require a continuous high-temperature environment which is rapidly generated, and have higher requirements on the stability of the environment.

For example, dense ceramic bodies are traditionally produced by high temperature sintering of green powders, a time and energy intensive process. High energy is required to maintain the feedstock in a high temperature (e.g., greater than 1000 degrees celsius) environment for long periods of time (greater than 30 minutes).

There is currently a new sintering method based on ultra-fast sintering, which can sinter ceramics in a few seconds, the process time being much shorter than conventional sintering. The reason for this technique to achieve ultra-fast and energy-saving is due to the use of graphite felt as the heating material. However, this technique has strong limitations and is only suitable for samples having a thickness of about 1 mm. This technique cannot be applied to large size samples because the thermal gradients formed during the ultra-fast heating and cooling stages can crack the heated workpiece during heating and cooling.

Rapid heating provides the added benefits of shortened grain growth time (i.e., maintaining a refined microstructure), significantly reduced dense activation energy, and controlled reactivity. This has proven to be significant in limiting reactivity and maintaining the integrity of the thin layers that make up the solid-state battery, reducing volatilization of volatile elements (i.e., lithium, sodium) during thermal processing. In the context of the rapid sintering technique, flash firing techniques have been proposed, which greatly reduce the time required for sintering, to a minimum of only a few seconds. The prior art typically uses external heating to trigger flash firing, and although attempts have been made successfully at lower temperatures, flash firing techniques are sensitive to the conductivity of the workpiece material to be cured and the geometry of the sample, meaning that the technique is difficult to apply to large-scale industrial production.

Against this background, the core problem of the described technology is to have a simple, efficient and highly adaptable ultra-fast heating device. Therefore, the utility model relates to a simple high-efficient and suitable for the super rapid heating device of extensive industrial application, very necessary.

SUMMERY OF THE UTILITY MODEL

The utility model provides an ultrafast heating sintering device, which aims to solve the technical problems that the conventional ultrafast heating sintering device is narrow in application range, poor in sample sintering quality and incapable of being applied in large-scale industrialization.

In order to solve the above technical problem, the present invention provides an ultrafast heat sintering apparatus, comprising:

the electric insulation heating cavity is arranged on an electrode plate in the electric insulation heating cavity, and a power supply is electrically connected with the electrode plate; high-melting-point conductive powder is filled in the electric insulation heating cavity and is electrically connected with the electrode slice; the high-melting-point conductive powder is coated on a workpiece to be heated;

the conductive powder of the heating cavity needs to be coated with a workpiece to be heated, the electrode plate needs to be inserted into the heating cavity filled with the conductive powder, the conductive powder in the heating cavity is subjected to conductive heating through the electrode plate connected with a power supply, and heat is transferred to the workpiece through conduction and/or radiation and/or convection, so that the required workpiece is heated at an ultra-fast speed.

Preferably, the ultrafast thermal sintering apparatus further comprises a pressing device in stress contact with the electrically insulated heating chamber.

Preferably, the ultrafast heating sintering device further comprises a temperature control device in thermal contact with the high-melting-point powder in the heating cavity.

Preferably, an electric insulation and heat insulation structure layer is arranged outside the conductive heating cavity.

Preferably, the high melting point conductive powder material comprises any one or more of graphite, carbon black, graphene, carbon nanotubes, silicon carbide, refractory metals and borides, carbides of tantalum, tungsten, niobium, and molybdenum. The conductivity will be reduced by the addition of non-conductive powder to any one or more of the mixtures of high melting point conductive powders as described above.

Preferably, the thickness of the workpiece to be heated is 0.001 to 400 mm.

The utility model also provides an ultrafast temperature rise reaction kettle of the ultrafast heating device, which comprises a high-temperature reaction kettle as the workpiece to be heated.

Compared with the prior art, the ultra-fast heating sintering device is simple in structure, parameters such as heating speed, temperature and time can be accurately controlled by controlling the power supply and matching with the temperature measuring device, high-melting-point conductive powder in the heating cavity can be attached to a workpiece more tightly through the pressing device, and the heating effect is better. Energy loss can be reduced through the heating cavity electric insulation heat insulation layer, the temperature uniformity of the heating area is improved, and finally the quality of the heated workpiece is obviously improved. Therefore, the ultrafast heating sintering device has the advantages of simple structure, strong function and good controllability. The conductive powder not subjected to external pressure has a low thermal conductivity (less than 5W/mK), thereby achieving workpiece heating with low heat loss.

The ultrafast sintering process adopts the conductive powder to coat the workpiece and electrically heat, so that the whole temperature rising and lowering process and the temperature preservation temperature are controllable, the conductive powder can be repeatedly used, the cost is low, and the ultrafast sintering process is suitable for standardization and industrial popularization. The prior art adopts graphite felt, and large-area graphite felt is expensive, can't avoid damaging in the sintering process, need be changed after limited use number of times, greatly increased cost, and in order to guarantee sintering efficiency, two graphite felts can't be too far apart, therefore restricted the size of treating the sintered work piece, and thickness can only be about a millimeter at most. The conductive powder used in the utility model has low cost and can be recycled. Furthermore, carbon contamination can be reduced by using a lower carbon content conductive powder in the crucible in which the workpiece is placed (lower carbon content conductive powders include graphite, carbon black, graphene, carbon nanotubes, silicon carbide, refractory metals and borides, mixtures of any one or more of carbides of tantalum, tungsten, niobium, molybdenum). By adopting the coating process, the limitation on the size of the heated workpiece is reduced, and workpieces with the size of 0.001-400mm can be heated and sintered at an ultra-fast speed. Therefore, the ultra-fast sintering process disclosed by the utility model is more excellent than the process in the prior art in terms of cost, realizability, application range and industrialization prospect.

The ultrafast welding process has the greatest advantages that the temperature rise is rapid, and the control of the temperature rise process and the temperature far exceed that of the traditional welding process; in addition, the energy utilization rate is greatly improved because the treatment is carried out in a relatively closed space. Therefore, the application range of the ultra-fast welding process disclosed by the utility model is greatly expanded, and material welding which cannot be realized by the traditional welding process can be carried out.

Compared with the existing reaction kettle, the ultrafast temperature rise reaction kettle has the advantages of rapid temperature rise, high temperature upper limit, continuity, adjustability, fine control and the like, and therefore has an application prospect of implementing controllable chemical reaction.

Compared with the existing smelting process, the ultra-fast smelting process has the greatest advantages that high temperature can be achieved at ultrahigh heating efficiency, and accurate temperature control can be carried out in a high temperature range. The method is very important for melting materials such as metal or ceramic by adopting the crucible heated in the heating cavity, so that the ultra-fast melting process has good application prospect.

Drawings

FIG. 1 is a schematic structural diagram of an ultrafast heating sintering apparatus according to an embodiment of the present invention;

FIG. 2 is a schematic cross-sectional view of an apparatus for ultrafast thermal sintering according to an embodiment of the present invention;

FIG. 3 is a schematic view of a temperature control device of the ultrafast sintering apparatus according to an embodiment of the present invention;

FIG. 4 is a process flow diagram of an ultra-fast sintering process according to an embodiment of the present invention;

FIG. 5 is a schematic diagram of an ultrafast welding process according to an embodiment of the present invention;

FIG. 6 is a schematic diagram of an apparatus for ultrafast temperature rise reaction according to an embodiment of the present invention;

fig. 7 is a schematic diagram of a smelting process of the ultrafast heating apparatus according to an embodiment of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be described below clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be obtained by a person skilled in the art without inventive step based on the embodiments of the present invention, are within the scope of the present invention.

It should be noted that all the directional indicators (such as up, down, left, right, front, and rear … …) in the embodiment of the present invention are only used to explain the relative position relationship and movement of each component in a specific posture (as shown in the figure), and if the specific posture is changed, the directional indicator is changed accordingly.

It will also be understood that when an element is referred to as being "secured to" or "disposed on" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present.

In addition, the descriptions related to "first", "second", etc. in the present invention are for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicit indication of the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the feature. In addition, technical solutions between various embodiments may be combined with each other, but must be realized by a person skilled in the art, and when the technical solutions are contradictory or cannot be realized, such a combination should not be considered to exist, and is not within the protection scope of the present invention.

In one aspect of the present invention, there is provided an ultrafast heating sintering apparatus, as shown in fig. 1 and 2, comprising: the device comprises an electric insulation heating cavity 0, an electrode plate 3 electrically connected with the electric insulation heating cavity, and a power supply 4 electrically connected with the electrode plate; in a particular embodiment, the power supply 4 is an adjustable power supply that may be operated in either an AC or DC mode. The electric insulation heating cavity is filled with high-melting-point conductive powder 2, and the high-melting-point conductive powder material comprises any one or mixture of more of graphite, carbon black, graphene, carbon nano tubes, silicon carbide, refractory metals and boride, carbides of tantalum, tungsten, niobium and molybdenum. The conductivity will be reduced by the addition of non-conductive powder to any one or more of the mixtures of high melting point conductive powders as described above.

Graphite carbon black, graphene, carbon nanotubes, refractory metals and borides and carbides thereof are all materials with ultrahigh conductivity and high melting point, and the powder price thereof is relatively low, so the cost is controlled while the process requirement is met. The high-melting-point conductive powder is coated on the workpiece 1 to be heated; the size range of the workpiece 1 to be heated is 0.001-400 mm. The pressing device 7 is in stress contact with the high-melting-point conductive powder 2 in the electric insulation heating cavity, the temperature measuring device 6 is in thermal contact with the high-melting-point conductive powder, and the temperature measuring device 6 can directly measure the temperature of a workpiece through the conductive powder in specific operation so as to obtain more accurate real-time temperature;

and a heat insulation electric insulation layer 5 is arranged outside the electric insulation heating cavity 0, and the heat insulation electric insulation layer 5 comprises an electric insulation layer 51 and a heat insulation layer 52. The power supply 4 is connected to the electrode plate 3 inserted into the electric insulation heating cavity 0 to heat the high-melting-point conductive powder 2 by the aid of the electric electrode plate 3 through the working principle of current-joule effect, so that heat energy is transferred to the workpiece 1 to be sintered, which is coated by the conductive powder 2, and the workpiece 1 is heated and sintered at an ultra-fast speed. The temperature is controlled by adjusting the power of the power supply and by the real-time feedback of the temperature measuring device 6;

in this embodiment, the pressure applying device 7 is in stress contact with the high melting point conductive powder 2 in the electrically insulated heating cavity 0, and as shown in fig. 2d), pressure can be applied uniaxially between the two electrodes 3, so that the high melting point conductive powder 2 and the workpiece 1 to be sintered are bonded more tightly and the heat transfer efficiency is higher. The heat insulation electric insulation layer 5 is arranged in a space formed by the outer layer of the electric insulation heating cavity 0 and can be filled with air, or filled with inert gases such as nitrogen and argon, or kept in vacuum and the like, so that the effects of atmosphere protection, air pressure application, heat preservation, heat insulation and the like are achieved.

In this embodiment, preferably, the present invention further includes a temperature control device in thermal contact with the refractory powder in the heating chamber.

Referring to fig. 3, the temperature control device includes a controller 61, an adjustable power supply 62, a current-voltage temperature display 63, and an ultrafast heater 64; the adjustable power supply 62 provides power to the controller and the current-voltage-temperature display; the controller 61 controls the ultra-fast heater 64 through the current-voltage temperature display 63;

in this embodiment, the controller 61 controls the ultrafast heater 64 to heat, that is, the temperature control device controls the ultrafast heater 64 to heat through the controller 61.

In this embodiment, preferably, the ultrafast heater 64 further includes a temperature detector 65 and a temperature display device 66; the temperature detector 65 is used for detecting temperature; the temperature display device 66 is used for displaying the temperature state.

The ultrafast sintering process provided by the embodiment of the utility model adopts a conductive powder electric heating mode, forms a heating mode with a wider, more uniform and more fitting temperature zone, can accurately control the temperature by regulating and controlling the current, and greatly expands the types and the range of heated materials. In addition, the graphite felt is not relied on, but graphite powder, so the shape of the workpiece is not required to be finished, and the shape applicability of the workpiece is greatly expanded. But also the size of the workpiece is not restricted due to different heating modes. The application range of the method is expanded in multiple aspects, so that the high-efficiency ultra-fast sintering process can be widely applied.

The embodiment of the utility model also provides an ultrafast sintering process based on the ultrafast heating sintering device, which comprises the following steps:

s01: coating a workpiece to be sintered by using high-melting-point conductive powder;

s02: electrifying to quickly heat the conductive powder and quickly sintering the workpiece to be sintered.

Specifically, in step S01, the material of the workpiece to be sintered includes any one or more of ceramics, metals, metal compounds, and ceramic precursors. The sintering process has controllable and adjustable temperature, so the utility model has wide application range, and wide melting point range of ceramics, metals, metal compounds and ceramic precursors, but is still applicable.

Specifically, in the step S02, the power-on process uses a controllable power source. The control can be realized through conventional regulation control, and can also be more intelligently controlled by using a program. As shown in fig. 3, the output power of the power supply, i.e. the power supply voltage, can be controlled by a controller 61, specifically by a computer, and applied to the conductive powder, and feedback-regulated by a temperature control device.

Specifically, in the step S01, the thickness of the workpiece to be sintered is 0.001 to 400 mm. Due to the process characteristics of the utility model, the coated powder has no problem of rapid attenuation of thermal radiation when the distance is too large, so that the size of a workpiece can be larger; and the powder coating preparation process can be suitable for workpieces with various complex shapes.

Specifically, in step S01, the refractory conductive powder is pressed on the workpiece to be sintered. The process can also apply pressure to the conductive powder to enable the conductive powder to be tightly coated on the workpiece, so that the heat transfer efficiency is higher, and the sintering is quicker and more uniform. More specifically, the pressure applying mode can be realized by adopting uniaxial pressure or isostatic pressure pressurized gas, and the highest pressure can reach 200 MPa.

In particular embodiments, no or little pressure is typically applied, and pressurization is typically used in special cases. The process adopts the closed heat insulation cavity to prevent heat from overflowing, so that the energy use efficiency can be greatly improved, and the size range of the workpiece is greatly increased due to the extremely high heating efficiency and the action principle of conductive powder coating, so that the process has high universality and can sinter workpieces with complex shapes. The process is very suitable for welding, smelting, chemical reaction and other applications because the process can allow the byproduct gas to be freely discharged. The utility model has wider application range, uses the electric insulation heating cavity to finish the required process, and has the advantages of high safety and energy utilization rate, convenient adjustment, wide temperature range, wide application range, fineness, controllability and the like.

In a specific implementation, as shown in fig. 4, the method includes preparing ceramic powder, compacting the ceramic powder into a green heatable workpiece, and the process includes binder removal, drying, and the like. Then, the ultrafast sintering process is adopted to realize ultrafast sintering, and the ceramic product is obtained.

In another aspect of the embodiments of the present invention, an ultrafast welding process based on the ultrafast heating sintering apparatus is provided, where the workpiece to be heated is a workpiece to be welded. The schematic view is shown in fig. 5, 1 is a workpiece to be heated in the apparatus, here a workpiece to be welded. The specific operation and use adjustments are consistent with the rapid sintering process and will not be repeated here. Arrows indicate that heat is supplied electrically.

The embodiment of the utility model also provides an ultrafast heating reaction kettle based on the ultrafast heating sintering device, which comprises a high-temperature reaction kettle used as the workpiece to be heated; and heating the workpiece to be reacted in a high-temperature reaction kettle. Such a reactor is advantageously used for carrying out any chemical reaction at high temperatures, including solid or liquid calcination, carbothermal or borothermal reduction, etc. The schematic view is shown in fig. 6, 1 is a workpiece to be reacted in the device, and 102 is a workpiece to be heated, namely a high-temperature reaction kettle. The specific operation is consistent with the adjustment and the rapid sintering process, and the description is not repeated here. Arrows indicate that joule heat is supplied in an energized manner.

In addition, the embodiment of the utility model also provides a smelting process based on the ultrafast heating sintering device. The smelting material in the first embodiment includes any one or more of metal or ceramic. Such a melting apparatus may be used to melt any metallic or ceramic material. Working principle as shown in the schematic view of fig. 7, the workpieces 1 to be melted are placed in a crucible 103 and heated together in a workpiece 102 to be heated. The specific operation is consistent with the adjustment and the rapid sintering process, and the description is not repeated here. Arrows indicate that joule heat is supplied in an energized manner.

The ultrafast heating sintering device disclosed by the embodiment of the utility model is simple and has control devices for control, feedback regulation, pressure regulation and the like, the quality of a workpiece can be ensured, and the application range of the device can be expanded. Because no special requirements or special parts are required for the structure, the device is convenient to manufacture, high in cost performance, simple to operate, high in applicability and suitable for large-scale popularization and application of standardization and industrialization.

It should be noted that, for the sake of simplicity, all the aforementioned embodiments are expressed as one.

Series of acts may be combined, it will be appreciated by those skilled in the art that the present invention is not limited by the order of acts described, as some steps may occur in other orders or concurrently with other steps in accordance with the utility model. Further, those skilled in the art should also appreciate that the embodiments described in the specification are preferred embodiments and that the acts and modules referred to are not necessarily required by the utility model.

In the embodiments provided in the present application, it should be understood that the disclosed apparatus may be implemented in other manners. For example, the above-described embodiments of the apparatus are merely illustrative, and for example, the above-described division of the units is only one type of division of logical functions, and other divisions may be realized in practice, for example, a plurality of units or components may be combined or integrated into another system, or some features may be omitted, or not executed. In addition, the shown or discussed mutual coupling or communication connection may be an indirect coupling or communication connection between devices or units through some interfaces, and may be in a telecommunication or other form.

The units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of the embodiment.

The above examples are only used to illustrate the technical solution of the present invention, and do not limit the scope of the present invention. It is to be understood that the described embodiments are merely exemplary of the utility model, and not restrictive of the full scope of the utility model. All other embodiments, which can be derived by a person skilled in the art from these embodiments without making any inventive step, fall within the scope of the present invention. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art may still make various combinations, additions, deletions or other modifications of the features of the embodiments of the present invention according to the situation without conflict, so as to obtain different technical solutions without substantially departing from the spirit of the present invention, and these technical solutions also fall within the protection scope of the present invention.

Claims

1. An ultrafast thermal sintering apparatus, comprising:

the electric insulation heating cavity is arranged on an electrode plate in the electric insulation heating cavity, and a power supply is electrically connected with the electrode plate; high-melting-point conductive powder is filled in the electric insulation heating cavity and is electrically connected with the electrode slice; the high-melting-point conductive powder is coated on a workpiece to be heated.

2. The apparatus of claim 1, further comprising a pressing means in stress contact with the high melting point conductive powder.

3. The apparatus of claim 1, further comprising a temperature control device in thermal contact with said refractory conductive powder.

4. The apparatus according to claim 1, wherein the electrically insulating heating cavity is further provided with a heat insulating layer.

5. The ultrafast heating sintering apparatus of claim 1, wherein the thickness of the workpiece to be heated is 0.001-400 mm.

6. An ultrafast heating-up reaction kettle based on the ultrafast heating apparatus as claimed in any one of claims 1 to 5, wherein the workpiece to be heated is a high temperature reaction kettle.