Method and equipment for improving dispersity of ceramic sintering powder

Abstract

The invention provides a method for improving dispersity of ceramic sintering powder. The method comprises the following steps: providing a sealed vacuum box in which an upper electrode, a lower electrode, an upper insulating medium plate and a lower insulating medium plate are arranged; laying ceramic sintering powder on the lower insulating dielectric plate; controlling the atmosphere in the sealed vacuum box; the alternating current power supply is turned on, and the upper electrode and the lower electrode generate dielectric barrier discharge plasma between the upper insulating dielectric plate and the lower insulating dielectric plate under the action of the alternating current power supply; and treating the ceramic sintering powder for a certain time by using the dielectric barrier discharge plasma. In addition, the invention further provides equipment for improving the dispersity of the ceramic sintering powder. By means of the method and equipment, the number of steps for improving the dispersity of the ceramic sintering powder is small, the equipment structure is simple, the overall production efficiency is greatly improved, and the ceramic sintering preparation cost is effectively reduced.

Description

Technical Field

[0001] The present application relates to the technical field of ceramic materials, and in particular to a method and a device for improving the dispersibility of ceramic sintered powder. Background Art

[0002] Ceramic materials are widely used in daily necessities, electric power industry, chemical industry, construction and other fields due to their excellent insulation, heat resistance, corrosion resistance and mechanical properties.

[0003] Sintering is a common method for preparing ceramics, and ceramic sintering powder is the key raw material for preparing ceramics by sintering. The performance of the powder has a significant impact on the subsequent sintering steps. Dispersibility is one of the key indicators to determine whether the powder is suitable for sintering. If the powder has good dispersibility, its powder particles are evenly dispersed. When it is used for sintering, the sintering temperature is low, the density of the sintered ceramic is high, and the grain size is evenly distributed, with excellent electrical, mechanical and thermal properties. On the contrary, if the powder has poor dispersibility and the powder particles agglomerate significantly, it will seriously affect the cost and product quality of preparing ceramics by sintering.

[0004] Compared with traditional engineering ceramics, nanoceramics have greatly improved properties such as strength, toughness and ductility, and have unique properties in electricity, heat, magnetism, light, etc., and have wide application potential. Nanopowder is the basic raw material for preparing nanoceramics, but nanopowder is very easy to agglomerate due to its high surface activity and poor dispersion, which is not conducive to subsequent sintering.

[0005] At present, methods to improve the dispersibility of ceramic sintered powders include passivation, additives, solvent storage and transportation, but they generally have problems such as high cost, low efficiency, and complex equipment. Summary of the invention

[0006] In view of this, it is necessary to provide a method and an apparatus for improving the dispersibility of ceramic sintered powder to solve the above problems.

[0007] Some embodiments of the present application provide a method for improving the dispersibility of ceramic sintered powder, the method comprising:

[0008] A sealed vacuum box is provided, wherein an upper electrode, a lower electrode, an upper insulating dielectric plate and a lower insulating dielectric plate are arranged in the sealed vacuum box, the upper insulating dielectric plate is spaced apart from and arranged opposite to the lower insulating dielectric plate, the upper electrode is connected to the upper insulating dielectric plate, the lower electrode is connected to the lower insulating dielectric plate, and the upper insulating dielectric plate and the lower insulating dielectric plate are both located between the upper electrode and the lower electrode, and the upper electrode and the lower electrode are respectively connected to an AC power supply;

[0009] Laying ceramic sintered powder on the lower insulating dielectric plate, wherein the ceramic sintered powder is located between the upper insulating dielectric plate and the lower insulating dielectric plate;

[0010] Controlling the atmosphere in the sealed vacuum box to be an inert atmosphere;

[0011] Turning on the AC power supply, the upper electrode and the lower electrode generate a dielectric barrier discharge plasma between the upper insulating dielectric plate and the lower insulating dielectric plate under the action of the AC power supply; and

[0012] The ceramic sintered powder is treated for a certain period of time using the dielectric barrier discharge plasma.

[0013] In some possible implementations, in the step of laying the ceramic sintered powder on the lower insulating dielectric plate, the ceramic sintered powder is a high-purity nano powder with a particle size of 10 nanometers to 20 nanometers.

[0014] In some possible implementations, in the step of laying the ceramic sintered powder on the lower insulating dielectric plate, the ceramic sintered powder is evenly laid on the lower insulating dielectric plate, and the thickness of the ceramic sintered powder is 0.2 mm-1 mm.

[0015] In some possible implementations, the dielectric barrier discharge plasma treats the ceramic sintered powder for 10 minutes to 30 minutes.

[0016] In some possible implementations, the method further includes: adjusting the voltage frequency of the AC power supply to 8 kHz-12 kHz and the voltage amplitude to 5 kilovolts-15 kilovolts.

[0017] In some possible implementations, the relationship between the change in the Zeta potential of the ceramic sintered powder before and after the dielectric barrier discharge plasma treatment and the voltage amplitude and treatment time is: Δζ=0.01356·V 1.8107 ·T 1.0798 , wherein Δζ is the Zeta potential difference of the ceramic sintered powder before and after being treated with the dielectric barrier discharge plasma, in millivolts, V is the voltage amplitude of the AC power supply, in kilovolts, and T is the treatment time of the ceramic sintered powder by the dielectric barrier discharge plasma, in minutes.

[0018] In some possible implementations, in the step of controlling the atmosphere in the sealed vacuum box, the atmosphere in the sealed vacuum box is adjusted to an inert atmosphere of 0.2 atm-1 atm.

[0019] The present application also provides a device for improving the dispersibility of ceramic sintered powder, the device comprising a sealed vacuum box, an AC power supply, a vacuum pump and a gas cylinder; an upper electrode, a lower electrode, an upper insulating dielectric plate and a lower insulating dielectric plate are arranged in the sealed vacuum box, the upper insulating dielectric plate and the lower insulating dielectric plate are spaced and arranged opposite to each other, the upper electrode is connected to the upper insulating dielectric plate, the lower electrode is connected to the lower insulating dielectric plate, and the upper insulating dielectric plate and the lower insulating dielectric plate are located between the upper electrode and the lower electrode, and the lower insulating dielectric plate is used to lay the ceramic sintered powder; the upper electrode and the lower electrode are respectively connected to the AC power supply; the vacuum pump is connected to the sealed vacuum box; the gas cylinder stores inert gas and is connected to the sealed vacuum box.

[0020] In some possible implementations, the AC power source has a voltage frequency of 8 kHz to 12 kHz and a voltage amplitude of 5 kilovolts to 15 kilovolts.

[0021] In some possible implementations, the thickness of the upper insulating dielectric plate is 0.5 mm-2 mm, the thickness of the lower insulating dielectric plate is 0.5 mm-2 mm, and the width of the air gap between the upper insulating dielectric plate and the lower insulating dielectric plate is 2 mm-4 mm.

[0022] Compared with the prior art, the aforementioned method and device of the present application uses dielectric barrier discharge plasma to treat and obtain ceramic sintered powder with high dispersibility in fewer steps, and the equipment structure for preparing dielectric barrier discharge plasma is simple, which greatly improves the overall production efficiency and effectively reduces the cost of ceramic sintering preparation. In addition, the treated ceramic sintered powder with high dispersibility can also improve the electrical, mechanical and thermal properties of sintered ceramic products. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0024] Figure 1 This is a flow chart of the steps of a method for improving the dispersibility of ceramic sintered powder according to some embodiments of the present application.

[0025] Figure 2 This is a schematic diagram of the structure of an apparatus for improving the dispersibility of ceramic sintered powder according to some embodiments of the present application.

[0026] Description of main component symbols:

[0027] DETAILED DESCRIPTION

[0028] The technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments.

[0029] It should be noted that when an element is referred to as being "fixed to" another element, it may be directly on the other element or there may also be a centered element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may also be a centered element. When an element is considered to be "set on" another element, it may be directly set on the other element or there may also be a centered element. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only.

[0030] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present application. The terms used herein in the specification of the present application are only for the purpose of describing specific embodiments and are not intended to limit the present application. The term "or / and" used herein includes any and all combinations of one or more related listed items.

[0031] Some embodiments of the present application are described in detail. In the absence of conflict, the following embodiments and features of the embodiments can be combined with each other.

[0032] See also Figure 1 and Figure 2 Some embodiments of the present application provide a method for improving the dispersibility of ceramic sintered powder, the method comprising the following steps:

[0033] S1: A sealed vacuum box 11 is provided, in which an upper electrode 22, a lower electrode 23, an upper insulating dielectric plate 12 and a lower insulating dielectric plate 13 are arranged, the upper insulating dielectric plate 12 and the lower insulating dielectric plate 13 are spaced apart and arranged opposite to each other, the upper electrode 22 is connected to the upper insulating dielectric plate 12, the lower electrode 23 is connected to the lower insulating dielectric plate 13, and the upper insulating dielectric plate 12 and the lower insulating dielectric plate 13 are both located between the upper electrode 22 and the lower electrode 23, and the upper electrode 22 and the lower electrode 23 are respectively connected to an AC power supply 21.

[0034] In some embodiments, the upper insulating dielectric plate 12 and the lower insulating dielectric plate 13 are aluminum oxide plates.

[0035] Of course, in other implementations, the upper insulating dielectric plate 12 and the lower insulating dielectric plate 13 may also be made of other insulating dielectric materials such as glass, ceramic, polymer, etc., which are not limited here.

[0036] In some embodiments, the thickness of the upper insulating dielectric plate 12 is 0.5 mm to 2 mm, and the thickness of the lower insulating dielectric plate 13 is 0.5 mm to 2 mm. Controlling the thickness of the insulating dielectric plate can avoid problems such as aggravated thermal effects and reduced material durability caused by too thin dielectric plates, and can also effectively avoid a series of problems such as a higher power supply voltage and poor discharge uniformity caused by too thick dielectric plates.

[0037] The specific sizes of the upper insulating dielectric plate 12 and the lower insulating dielectric plate 13 can be adaptively adjusted according to actual needs and are not limited here.

[0038] In some embodiments, the width of the air gap between the upper insulating dielectric plate 12 and the lower insulating dielectric plate 13 is 2 mm to 4 mm.

[0039] In some embodiments, a support member 14 is further disposed in the sealed vacuum box 11, and the upper electrode 22 and the lower electrode 23 are disposed in the sealed vacuum box 11 by means of the support member 14. In addition, the support member 14 can also be used to adjust the relative position between the upper electrode 23 and the lower electrode 24, thereby adjusting the air gap width between the upper insulating dielectric plate 12 and the lower insulating dielectric plate 13.

[0040] Of course, in some other embodiments, the support member 14 may be omitted.

[0041] S2: laying the ceramic sintered powder 40 on the lower insulating dielectric plate 13 , wherein the ceramic sintered powder 40 is located between the upper insulating dielectric plate 12 and the lower insulating dielectric plate 13 .

[0042] In some embodiments, the ceramic sintered powder 40 is evenly spread on the lower insulating dielectric plate 13 , so that the ceramic sintered powder 40 is evenly processed, ensuring the efficiency and quality of the processing.

[0043] In some embodiments, the thickness of the ceramic sintered powder 40 laid on the lower insulating dielectric plate 13 is 0.2 mm-1 mm to ensure the efficiency and quality of the ceramic sintered powder 40. It can be understood that when the thickness of the ceramic sintered powder 40 is too thin, it will lead to a small single processing amount and low processing efficiency. If the efficiency of processing the same processing amount of ceramic sintered powder 40 is to be guaranteed when the thickness is too thin, a larger powder laying area is required, which will put higher requirements on the electrode and the insulating dielectric plate, and the processing cost of the ceramic sintered powder 40 will also increase significantly; and when the thickness of the ceramic sintered powder 40 is too thick, it will lead to poor processing uniformity, and it is impossible to obtain high-quality ceramic sintered powder 40 with good dispersion.

[0044] In some embodiments, the ceramic sintered powder 40 is a high-purity nano powder with a particle size of 10 nanometers to 20 nanometers.

[0045] The ceramic sintered powder 40 is not limited to high-purity zinc oxide nanopowder, but may also be other high-purity nanopowders such as silicon carbide and zirconium oxide, which are not limited here.

[0046] S3: Controlling the atmosphere in the sealed vacuum box 11, wherein the atmosphere is an inert atmosphere.

[0047] Furthermore, the atmosphere of the sealed vacuum box is adjusted to an inert atmosphere of 0.2atm-1atm to ensure discharge uniformity. It can be understood that appropriate low pressure is conducive to reducing the required power supply voltage and improving discharge uniformity; while too low pressure will lead to insufficient discharge power, and too high pressure will lead to concentrated and unstable discharge, affecting processing efficiency and quality.

[0048] The inert atmosphere is not limited to argon, but may also be other inert gases such as helium, which is not limited here.

[0049] In some embodiments, the sealed vacuum box 11 is also connected to a vacuum pump 31 and a gas cylinder 32, so that the atmosphere and pressure in the sealed vacuum box 11 can be controlled by means of the vacuum pump 31 and the gas cylinder 32. The gas cylinder 32 stores an inert gas.

[0050] Furthermore, air valves 33 are provided on the pipelines connecting the sealed vacuum box 11 and the vacuum pump 31, and on the pipelines connecting the sealed vacuum box 11 and the gas cylinder 32. The air valves 33 are used to control the opening and closing of the connected pipelines to adjust the air pressure in the sealed vacuum box 11 and the amount of inert gas injected. The sealed vacuum box 11 is also connected to a pressure gauge 34. The pressure gauge 34 is used to display the air pressure in the sealed vacuum box 11, so as to facilitate the control of the atmosphere in the sealed vacuum box 11.

[0051] S4: Turn on the AC power supply 21 , and the upper electrode 22 and the lower electrode 23 generate dielectric barrier discharge plasma between the upper insulating dielectric plate 12 and the lower insulating dielectric plate 13 under the action of the AC power supply 21 .

[0052] In some embodiments, the voltage frequency of the AC power supply 21 is 8-12 kHz, and the voltage amplitude is 5 kV-15 kV to avoid the high breakdown risk caused by using too high voltage, and the higher requirements for power supply and heat dissipation, which leads to increased processing costs and safety costs.

[0053] S5: The ceramic sintered powder 40 is treated by dielectric barrier discharge plasma for a certain period of time.

[0054] In some embodiments, the dielectric barrier discharge plasma treatment time of the ceramic sintered powder 40 is 10 minutes to 30 minutes.

[0055] It can be understood that the method for improving the dispersibility of ceramic sintered powder in some embodiments of the present application generates a dielectric barrier discharge plasma between the upper insulating medium 12 and the lower insulating medium plate 13 when the AC power supply is turned on by means of a dielectric barrier discharge device composed of various structures in the sealed vacuum box 11, and the steps of using the dielectric barrier discharge plasma to obtain ceramic sintered powder with high dispersibility are few, and the equipment structure for preparing the dielectric barrier discharge plasma is simple, which greatly improves the overall production efficiency and effectively reduces the cost of ceramic sintering preparation. In addition, the sintered ceramic products using the treated ceramic sintered powder with high dispersibility have greatly improved electrical, mechanical and thermal properties.

[0056] In some embodiments, the relationship between the change in the Zeta potential of the ceramic sintered powder 40 before and after the dielectric barrier discharge plasma treatment and the voltage amplitude and treatment time is:

[0057] Δζ=0.01356·V 1.8107 ·T 1.0798

[0058] Among them, Δζ is the Zeta potential difference of the ceramic sintered powder 40 before and after the dielectric barrier discharge plasma treatment, in millivolts, V is the voltage amplitude of the AC power supply, in kilovolts, and T is the treatment time of the ceramic sintered powder 40 by the dielectric barrier discharge plasma, in minutes.

[0059] It can be understood that the higher the Zeta potential value, the better the powder dispersibility. Δζ increases with the increase of V and T, that is, the improvement effect of dielectric barrier discharge plasma treatment on the dispersibility of ceramic sintered powder 40 increases with the increase of voltage amplitude and treatment time.

[0060] In some embodiments, the method for improving the dispersibility of ceramic sintered powder further includes, before step S2: drying the ceramic sintered powder by baking or other methods, which can effectively improve the use efficiency of the ceramic sintered powder.

[0061] It can be understood that the method of improving the dispersibility of ceramic sintered powder in the present application is not limited by the order of the above step descriptions. As long as the treatment of the ceramic sintered powder 40 by the dielectric barrier discharge plasma can be completed, there is no limitation on the order of the steps.

[0062] The scheme of the present application will be explained below in conjunction with the embodiments. Those skilled in the art will understand that the following examples are only used to explain the present application and cannot be construed as limiting the present application. Unless otherwise stated, the reagents, software and instruments not specifically stated in the following embodiments are all conventional commercial products or open source.

[0063] Example 1

[0064] (1) A sealed vacuum box 11 is provided. An upper electrode 22, a lower electrode 23, an upper insulating dielectric plate 12, a lower insulating dielectric plate 13 and a support member 14 are arranged in the sealed vacuum box 11. The upper electrode 22 and the lower electrode 23 are both arranged on the support member 14 and are respectively connected to the AC power supply 21. The upper insulating dielectric plate 12 is connected to the upper electrode 22, and the lower insulating dielectric plate 13 is connected to the lower electrode 23. The upper insulating dielectric plate 12 and the lower insulating dielectric plate 13 are spaced and arranged opposite to each other, and the upper insulating dielectric plate 12 and the lower insulating dielectric plate 13 are located between the upper electrode 22 and the lower electrode 23. The air gap width between the upper insulating dielectric plate 12 and the lower insulating dielectric plate 13 is 3 mm. The upper insulating dielectric plate 12 and the lower insulating dielectric plate 13 are both aluminum oxide plates.

[0065] (2) Selecting a ceramic sintered powder with a particle size of 10 nanometers to 20 nanometers and drying it. The ceramic sintered powder in Example 1 is a high-purity zinc oxide nanopowder.

[0066] (3) The dried high-purity zinc oxide nanopowder is evenly spread on the lower insulating dielectric plate 13 of 50 mm×50 mm×1 mm. The thickness of the high-purity zinc oxide nanopowder spread on the lower insulating dielectric plate 13 is 0.5 mm.

[0067] (4) The atmosphere in the sealed vacuum box 11 is adjusted to an argon atmosphere of 0.5 atm.

[0068] (5) Turn on the AC power supply 21. Under the action of the AC power supply 21, the upper electrode 22 and the lower electrode 23 generate a dielectric barrier discharge plasma between the upper insulating dielectric plate 12 and the lower insulating dielectric plate 13. The voltage frequency of the AC power supply is 10 kHz and the voltage amplitude is 5 kilovolts.

[0069] (6) High-purity zinc oxide nanopowder was treated with dielectric barrier discharge plasma for 10 minutes.

[0070] (7) Turn off the power and collect the processed powder.

[0071] (8) Test the processed powder.

[0072] The ceramic sintered powder before and after treatment was tested by BET specific surface area analysis tester. The test showed that the specific surface area of ​​the ceramic sintered powder before treatment was 23.377m 2 g -1 The specific surface area of ​​the ceramic sintered powder after dielectric barrier discharge plasma treatment is 26.712m 2 g -1 It can be seen that the specific surface area of ​​the ceramic sintered powder treated with dielectric barrier discharge plasma is increased by 14.27% compared with the untreated ceramic sintered powder.

[0073] The dispersibility of the ceramic sintered powder before and after treatment was characterized by the determination of Zeta potential. Specifically, the ceramic sintered powder was dispersed in anhydrous ethanol, the pH value was adjusted with sodium hydroxide, and after magnetic stirring and ultrasonic dispersion treatment at room temperature, the Zeta potential value of the powder before and after dielectric barrier discharge plasma treatment was tested with a NanoZS Zeta potential meter. Among them, the Zeta potential value of the powder before the dielectric barrier discharge plasma treatment was -14.6mV, the Zeta potential value of the powder after the dielectric barrier discharge plasma treatment was -17.5mV, and the Zeta potential difference of the powder before and after the dielectric barrier discharge plasma treatment was 2.9mV.

[0074] The voltage amplitude V in Example 1 is 5 kV, the treatment time is 10 minutes, and Δζ=0.01356·V 1.8107 ·T 1.0798 The calculated Δζ is 3.00389 mV.

[0075] Example 2

[0076] (1) A sealed vacuum box 11 is provided. An upper electrode 22, a lower electrode 23, an upper insulating dielectric plate 12, a lower insulating dielectric plate 13 and a support member 14 are arranged in the sealed vacuum box 11. The upper electrode 22 and the lower electrode 23 are both arranged on the support member 14 and are respectively connected to the AC power supply 21. The upper insulating dielectric plate 12 is connected to the upper electrode 22, and the lower insulating dielectric plate 13 is connected to the lower electrode 23. The upper insulating dielectric plate 12 and the lower insulating dielectric plate 13 are spaced and arranged opposite to each other, and the upper insulating dielectric plate 12 and the lower insulating dielectric plate 13 are located between the upper electrode 22 and the lower electrode 23. The air gap width between the upper insulating dielectric plate 12 and the lower insulating dielectric plate 13 is 3 mm. The upper insulating dielectric plate 12 and the lower insulating dielectric plate 13 are both aluminum oxide plates.

[0077] (2) Selecting a ceramic sintered powder with a particle size of 10 nanometers to 20 nanometers and drying it. The ceramic sintered powder in Example 2 is a high-purity zinc oxide nanopowder.

[0078] (3) The dried high-purity zinc oxide nanopowder is evenly spread on the lower insulating dielectric plate 13 of 50 mm×50 mm×1 mm. The thickness of the high-purity zinc oxide nanopowder spread on the lower insulating dielectric plate 13 is 0.5 mm.

[0079] (4) The atmosphere in the sealed vacuum box 11 is adjusted to an argon atmosphere of 0.5 atm.

[0080] (5) Turn on the AC power supply 21. Under the action of the AC power supply 21, the upper electrode 22 and the lower electrode 23 generate a dielectric barrier discharge plasma between the upper insulating dielectric plate 12 and the lower insulating dielectric plate 13. The AC power supply has a voltage frequency of 10 kHz and a voltage amplitude of 10 kilovolts.

[0081] (6) High-purity zinc oxide nanopowder was treated with dielectric barrier discharge plasma for 10 minutes.

[0082] (7) Turn off the power and collect the processed powder.

[0083] (8) Test the processed powder.

[0084] The ceramic sintered powder before and after treatment was tested by BET specific surface area analysis tester. The test showed that the specific surface area of ​​the ceramic sintered powder before treatment was 22.835m 2 g -1 The specific surface area of ​​the ceramic sintered powder after dielectric barrier discharge plasma treatment is 27.681m 2 g -1 It can be seen that the specific surface area of ​​the ceramic sintered powder treated by dielectric barrier discharge plasma is increased by 21.22% compared with the untreated ceramic sintered powder.

[0085] The dispersibility of the ceramic sintered powder before and after treatment was characterized by the determination of Zeta potential. Specifically, the ceramic sintered powder was dispersed in anhydrous ethanol, the pH value was adjusted with sodium hydroxide, and after magnetic stirring and ultrasonic dispersion treatment at room temperature, the Zeta potential value of the powder before and after dielectric barrier discharge plasma treatment was tested with a NanoZS Zeta potential meter. Among them, the Zeta potential value of the powder before the dielectric barrier discharge plasma treatment was -13.4mV, the Zeta potential value of the powder after the dielectric barrier discharge plasma treatment was -24mV, and the Zeta potential difference of the powder before and after the dielectric barrier discharge plasma treatment was 10.6mV.

[0086] The voltage amplitude V in Example 2 is 10 kV, the treatment time is 10 minutes, and Δζ=0.01356·V 1.8107 ·T 1.0798 The calculated Δζ is 10.53803 mV.

[0087] Example 3

[0088] (1) A sealed vacuum box 11 is provided. An upper electrode 22, a lower electrode 23, an upper insulating dielectric plate 12, a lower insulating dielectric plate 13 and a support member 14 are arranged in the sealed vacuum box 11. The upper electrode 22 and the lower electrode 23 are both arranged on the support member 14 and are respectively connected to the AC power supply 21. The upper insulating dielectric plate 12 is connected to the upper electrode 22, and the lower insulating dielectric plate 13 is connected to the lower electrode 23. The upper insulating dielectric plate 12 and the lower insulating dielectric plate 13 are spaced and arranged opposite to each other, and the upper insulating dielectric plate 12 and the lower insulating dielectric plate 13 are located between the upper electrode 22 and the lower electrode 23. The air gap width between the upper insulating dielectric plate 12 and the lower insulating dielectric plate 13 is 3 mm. The upper insulating dielectric plate 12 and the lower insulating dielectric plate 13 are both aluminum oxide plates.

[0089] (2) Selecting a ceramic sintered powder with a particle size of 10 nanometers to 20 nanometers and drying it. The ceramic sintered powder in Example 3 is a high-purity zinc oxide nanopowder.

[0090] (3) The dried high-purity zinc oxide nanopowder is evenly spread on the lower insulating dielectric plate 13 of 50 mm×50 mm×1 mm. The thickness of the high-purity zinc oxide nanopowder spread on the lower insulating dielectric plate 13 is 0.5 mm.

[0091] (4) The atmosphere in the sealed vacuum box 11 is adjusted to an argon atmosphere of 0.5 atm.

[0092] (5) Turn on the AC power supply 21. Under the action of the AC power supply 21, the upper electrode 22 and the lower electrode 23 generate a dielectric barrier discharge plasma between the upper insulating dielectric plate 12 and the lower insulating dielectric plate 13. The voltage frequency of the AC power supply is 10 kHz and the voltage amplitude is 5 kilovolts.

[0093] (6) High-purity zinc oxide nanopowder was treated with dielectric barrier discharge plasma for 30 minutes.

[0094] (7) Turn off the power and collect the processed powder.

[0095] (8) Test the processed powder.

[0096] The ceramic sintered powder before and after treatment was tested by BET specific surface area analysis tester. The specific surface area of ​​the ceramic sintered powder before treatment was 23.102m 2 g -1 The specific surface area of ​​the ceramic sintered powder after dielectric barrier discharge plasma treatment is 31.397m 2 g -1 It can be seen that the specific surface area of ​​the ceramic sintered powder treated with dielectric barrier discharge plasma is increased by 35.91% compared with the untreated ceramic sintered powder.

[0097] The dispersibility of the ceramic sintered powder before and after treatment was characterized by the determination of Zeta potential. Specifically, the ceramic sintered powder was dispersed in anhydrous ethanol, the pH value was adjusted with sodium hydroxide, and after magnetic stirring and ultrasonic dispersion treatment at room temperature, the Zeta potential value of the powder before and after dielectric barrier discharge plasma treatment was tested with a NanoZS Zeta potential meter. Among them, the Zeta potential value of the powder before the dielectric barrier discharge plasma treatment was -13.3mV, the Zeta potential value of the powder after the dielectric barrier discharge plasma treatment was -23.2mV, and the Zeta potential difference of the powder before and after the dielectric barrier discharge plasma treatment was 9.9mV.

[0098] The voltage amplitude V in Example 3 is 5 kV, the treatment time is 30 minutes, and Δζ=0.01356·V 1.8107 ·T 1.0798 The calculated Δζ is 9.83740 mV.

[0099] Example 4

[0100] (1) A sealed vacuum box 11 is provided. An upper electrode 22, a lower electrode 23, an upper insulating dielectric plate 12, a lower insulating dielectric plate 13 and a support member 14 are arranged in the sealed vacuum box 11. The upper electrode 22 and the lower electrode 23 are both arranged on the support member 14 and are respectively connected to the AC power supply 21. The upper insulating dielectric plate 12 is connected to the upper electrode 22, and the lower insulating dielectric plate 13 is connected to the lower electrode 23. The upper insulating dielectric plate 12 and the lower insulating dielectric plate 13 are spaced and arranged opposite to each other, and the upper insulating dielectric plate 12 and the lower insulating dielectric plate 13 are located between the upper electrode 22 and the lower electrode 23. The air gap width between the upper insulating dielectric plate 12 and the lower insulating dielectric plate 13 is 3 mm. The upper insulating dielectric plate 12 and the lower insulating dielectric plate 13 are both aluminum oxide plates.

[0101] (2) Selecting a ceramic sintered powder with a particle size of 10 nanometers to 20 nanometers and drying it. The ceramic sintered powder in Example 4 is a high-purity zinc oxide nanopowder.

[0102] (3) The dried high-purity zinc oxide nanopowder is evenly spread on the lower insulating dielectric plate 13 of 50 mm×50 mm×1 mm. The thickness of the high-purity zinc oxide nanopowder spread on the lower insulating dielectric plate 13 is 0.5 mm.

[0103] (4) The atmosphere in the sealed vacuum box 11 is adjusted to an argon atmosphere of 0.5 atm.

[0104] (5) Turn on the AC power supply 21. Under the action of the AC power supply 21, the upper electrode 22 and the lower electrode 23 generate a dielectric barrier discharge plasma between the upper insulating dielectric plate 12 and the lower insulating dielectric plate 13. The AC power supply has a voltage frequency of 10 kHz and a voltage amplitude of 10 kilovolts.

[0105] (6) High-purity zinc oxide nanopowder was treated with dielectric barrier discharge plasma for 30 minutes.

[0106] (7) Turn off the power and collect the processed powder.

[0107] (8) Test the processed powder.

[0108] The ceramic sintered powder before and after treatment was tested by BET specific surface area analysis tester. The test showed that the specific surface area of ​​the ceramic sintered powder before treatment was 23.264m 2 g -1 The specific surface area of ​​the ceramic sintered powder after dielectric barrier discharge plasma treatment is 32.093m 2 g -1 It can be seen that the specific surface area of ​​the ceramic sintered powder treated by dielectric barrier discharge plasma is increased by 37.95% compared with the untreated ceramic sintered powder.

[0109] The dispersibility of the ceramic sintered powder before and after treatment was characterized by the determination of Zeta potential. Specifically, the ceramic sintered powder was dispersed in anhydrous ethanol, the pH value was adjusted with sodium hydroxide, and after magnetic stirring and ultrasonic dispersion treatment at room temperature, the Zeta potential value of the powder before and after dielectric barrier discharge plasma treatment was tested with a NanoZS Zeta potential meter. Among them, the Zeta potential value of the powder before the dielectric barrier discharge plasma treatment was -14.2mV, the Zeta potential value of the powder after the dielectric barrier discharge plasma treatment was -48.8mV, and the Zeta potential difference of the powder before and after the dielectric barrier discharge plasma treatment was 34.6mV.

[0110] The voltage amplitude V in Example 4 is 5 kV, the treatment time is 10 minutes, and Δζ=0.01356·V 1.8107 ·T 1.0798 The calculated Δζ is 34.51082 mV.

[0111] Table 1, the processing conditions of the ceramic sintered powder in each embodiment and the test data before and after the processing.

[0112]

[0113] Combined with Examples 1-4, through the determination of specific surface area and Zeta potential, it can be seen that the use of dielectric barrier discharge plasma to treat ceramic sintered powder can effectively improve the dispersion performance of ceramic powder; and the improvement effect of dielectric barrier discharge plasma treatment on the dispersion of ceramic sintered powder increases with the increase of voltage amplitude and treatment time. Among them, the Zeta potential difference of the powder before and after dielectric barrier discharge plasma treatment is 2.9mV-35mV, and the specific surface area of ​​the ceramic sintered powder after dielectric barrier discharge plasma treatment is increased by 14%-40% compared with the untreated ceramic sintered powder.

[0114] See also Figure 2 Some embodiments of the present application also provide a device 100 for improving the dispersibility of ceramic sintered powder, including a sealed vacuum box 11, an AC power supply 21, a vacuum pump 31 and a gas cylinder 32. An upper electrode 23, a lower electrode 24, an upper insulating dielectric plate 12 and a lower insulating dielectric plate 13 are arranged in the sealed vacuum box 11. The upper insulating dielectric plate 12 and the lower insulating dielectric plate 13 are spaced and arranged opposite to each other, and the lower insulating dielectric plate 13 is used to lay the ceramic sintered powder. The upper electrode 22 is connected to the upper insulating dielectric plate 12, the lower electrode 23 is connected to the lower insulating dielectric plate 13, and the upper insulating dielectric plate 12 and the lower insulating dielectric plate 13 are both located between the upper electrode 22 and the lower electrode 23, and the upper electrode 22 and the lower electrode 23 are respectively connected to the AC power supply 21. The vacuum pump 31 is connected to the sealed vacuum box 11; the gas cylinder 32 stores inert gas, and the gas cylinder 32 is connected to the sealed vacuum box 11. The vacuum pump 31 and the gas cylinder 32 are used in conjunction to control the atmosphere in the sealed vacuum box 11.

[0115] In some embodiments, the device 100 for improving the dispersibility of ceramic sintered powder further includes a support member 14, which is installed in the sealed vacuum box 11, and the upper electrode 23 and the lower electrode 24 are fixed to the support member 14. The support member 14 can also be used to adjust the relative position between the upper electrode 23 and the lower electrode 24, thereby adjusting the air gap width between the upper insulating dielectric plate 12 and the lower insulating dielectric plate 13.

[0116] In some embodiments, the width of the air gap between the upper insulating dielectric plate 12 and the lower insulating dielectric plate 13 is 2 mm to 4 mm.

[0117] Of course, in some other embodiments, the support member 14 may be omitted.

[0118] In some embodiments, the device 100 for improving the dispersibility of ceramic sintered powder further includes two conductive pillars 22, and the two conductive pillars 22 are respectively connected to an AC power source 21; the conductive pillars 22 are arranged in the sealed vacuum box 11 and pass through the box. The upper electrode 23 is arranged between the upper insulating dielectric plate 12 and one conductive pillar 22 and connected in series with the two, and the lower electrode 24 is arranged between the lower insulating dielectric plate 13 and another conductive pillar 22 and connected in series with the two. The AC power source 21 is connected to the upper insulating dielectric plate 12 and the lower insulating dielectric plate 13 through the upper and lower electrodes, respectively. Turn on the AC power source 21, apply an AC voltage between the upper electrode 22 and the lower electrode 23, so that a dielectric barrier discharge plasma is generated between the upper insulating dielectric plate 12 and the lower insulating dielectric plate 13.

[0119] In some embodiments, the device 100 for improving the dispersibility of ceramic sintered powder further includes a pressure gauge 34 and two gas valves 33, which are respectively arranged on the pipeline connecting the sealed vacuum box 11 and the vacuum pump 31, and the pipeline connecting the sealed vacuum box 11 and the gas cylinder 32, to control the opening and closing of the two connecting pipelines, and adjust the air pressure and the amount of inert gas injected in the sealed vacuum box 11. The pressure gauge 34 is connected to the sealed vacuum box 11 to display the air pressure in the sealed vacuum box 11, so as to facilitate the control of the atmosphere in the sealed vacuum box 11.

[0120] The above implementation modes are only used to illustrate the technical solutions of the present application and are not intended to limit the present application. Although the present application has been described in detail with reference to the above preferred implementation modes, a person skilled in the art should understand that the technical solutions of the present application may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present application.

Claims

1. A method for improving the dispersibility of ceramic sintered powder, characterized in that: The method comprises: A sealed vacuum box is provided, wherein an upper electrode, a lower electrode, an upper insulating dielectric plate and a lower insulating dielectric plate are arranged in the sealed vacuum box, the upper insulating dielectric plate is spaced apart from and arranged opposite to the lower insulating dielectric plate, the upper electrode is connected to the upper insulating dielectric plate, the lower electrode is connected to the lower insulating dielectric plate, and the upper insulating dielectric plate and the lower insulating dielectric plate are both located between the upper electrode and the lower electrode, and the upper electrode and the lower electrode are respectively connected to an AC power supply; Laying ceramic sintered powder on the lower insulating dielectric plate, wherein the ceramic sintered powder is located between the upper insulating dielectric plate and the lower insulating dielectric plate; Controlling the atmosphere in the sealed vacuum box to be an inert atmosphere; Turning on the AC power supply, the upper electrode and the lower electrode generate a dielectric barrier discharge plasma between the upper insulating dielectric plate and the lower insulating dielectric plate under the action of the AC power supply; and The ceramic sintered powder is treated for a certain period of time using the dielectric barrier discharge plasma.

2. The method for improving the dispersibility of ceramic sintered powder according to claim 1, characterized in that: In the step of laying the ceramic sintered powder on the lower insulating dielectric plate, the ceramic sintered powder is a high-purity nano powder with a particle size of 10 nanometers to 20 nanometers.

3. The method for improving the dispersibility of ceramic sintered powder according to claim 1, characterized in that: In the step of laying the ceramic sintered powder on the lower insulating dielectric plate, the ceramic sintered powder is evenly laid on the lower insulating dielectric plate, and the thickness of the ceramic sintered powder is 0.2 mm-1 mm.

4. The method for improving the dispersibility of ceramic sintered powder according to any one of claims 1 to 3, characterized in that: The dielectric barrier discharge plasma treats the ceramic sintered powder for 10 minutes to 30 minutes.

5. The method for improving the dispersibility of ceramic sintered powder according to claim 4, characterized in that: The method further comprises: The voltage frequency of the AC power supply is adjusted to 8 kHz-12 kHz, and the voltage amplitude is adjusted to 5 kilovolts-15 kilovolts.

6. The method for improving the dispersibility of ceramic sintered powder according to claim 5, characterized in that: The relationship between the change in the Zeta potential of the ceramic sintered powder before and after the dielectric barrier discharge plasma treatment and the voltage amplitude and treatment time is: Δζ=0.01356·V 1.8107 ·T 1.0798 , wherein Δζ is the Zeta potential difference of the ceramic sintered powder before and after being treated with the dielectric barrier discharge plasma, in millivolts, V is the voltage amplitude of the AC power supply, in kilovolts, and T is the treatment time of the ceramic sintered powder by the dielectric barrier discharge plasma, in minutes.

7. The method for improving the dispersibility of ceramic sintered powder according to claim 1, 2, 3, 5 or 6, characterized in that: In the step of controlling the atmosphere in the sealed vacuum box, the atmosphere in the sealed vacuum box is adjusted to an inert atmosphere of 0.2atm-1atm.

8. A device for improving the dispersibility of ceramic sintered powder, characterized in that: The device comprises: A sealed vacuum box, wherein an upper electrode, a lower electrode, an upper insulating dielectric plate and a lower insulating dielectric plate are arranged in the sealed vacuum box, the upper insulating dielectric plate and the lower insulating dielectric plate are spaced and arranged opposite to each other, the upper electrode is connected to the upper insulating dielectric plate, the lower electrode is connected to the lower insulating dielectric plate, and the upper insulating dielectric plate and the lower insulating dielectric plate are located between the upper electrode and the lower electrode, and the lower insulating dielectric plate is used to lay the ceramic sintered powder; An AC power source, the upper electrode and the lower electrode are respectively connected to the AC power source; a vacuum pump connected to the sealed vacuum box; and A gas cylinder stores inert gas, and the gas cylinder is connected to the sealed vacuum box.

9. The device for improving the dispersibility of ceramic sintered powder according to claim 8, characterized in that: The voltage frequency of the AC power supply is 8 kHz-12 kHz, and the voltage amplitude is 5 kilovolts-15 kilovolts.

10. The device for improving the dispersibility of ceramic sintered powder according to claim 8 or claim 9, characterized in that: The thickness of the upper insulating dielectric plate is 0.5 mm to 2 mm, the thickness of the lower insulating dielectric plate is 0.5 mm to 2 mm, and the width of the air gap between the upper insulating dielectric plate and the lower insulating dielectric plate is 2 mm to 4 mm.

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