CN117534500A - Purifying method of carbon-carbon composite material - Google Patents
Purifying method of carbon-carbon composite material Download PDFInfo
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- CN117534500A CN117534500A CN202311776232.1A CN202311776232A CN117534500A CN 117534500 A CN117534500 A CN 117534500A CN 202311776232 A CN202311776232 A CN 202311776232A CN 117534500 A CN117534500 A CN 117534500A
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- composite material
- freon
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- 239000002131 composite material Substances 0.000 title claims abstract description 50
- CREMABGTGYGIQB-UHFFFAOYSA-N carbon carbon Chemical compound C.C CREMABGTGYGIQB-UHFFFAOYSA-N 0.000 title claims abstract description 48
- 239000011203 carbon fibre reinforced carbon Substances 0.000 title claims abstract description 48
- 238000000034 method Methods 0.000 title claims abstract description 40
- 238000000746 purification Methods 0.000 claims abstract description 65
- XKRFYHLGVUSROY-UHFFFAOYSA-N argon Substances [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 claims abstract description 53
- 229910052786 argon Inorganic materials 0.000 claims abstract description 41
- 239000007789 gas Substances 0.000 claims abstract description 38
- 239000000203 mixture Substances 0.000 claims abstract description 23
- 238000010438 heat treatment Methods 0.000 claims abstract description 11
- 239000000463 material Substances 0.000 abstract description 17
- 239000012535 impurity Substances 0.000 abstract description 13
- 238000000605 extraction Methods 0.000 description 8
- 238000012360 testing method Methods 0.000 description 8
- 238000005086 pumping Methods 0.000 description 5
- 238000001816 cooling Methods 0.000 description 4
- 239000000126 substance Substances 0.000 description 4
- 230000000694 effects Effects 0.000 description 3
- 238000009991 scouring Methods 0.000 description 3
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 2
- 238000009529 body temperature measurement Methods 0.000 description 2
- 238000011161 development Methods 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 238000004321 preservation Methods 0.000 description 2
- HBMJWWWQQXIZIP-UHFFFAOYSA-N silicon carbide Chemical compound [Si+]#[C-] HBMJWWWQQXIZIP-UHFFFAOYSA-N 0.000 description 2
- OYPRJOBELJOOCE-UHFFFAOYSA-N Calcium Chemical compound [Ca] OYPRJOBELJOOCE-UHFFFAOYSA-N 0.000 description 1
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical compound C[C@@H]1CC[C@@]2(CC[C@@]3(C(=CC[C@H]4[C@]3(CC[C@@H]5[C@@]4(CC[C@@H](C5(C)C)OS(=O)(=O)[O-])C)C)[C@@H]2[C@]1(C)O)C)C(=O)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O)O)O.[Na+] DGAQECJNVWCQMB-PUAWFVPOSA-M 0.000 description 1
- FYYHWMGAXLPEAU-UHFFFAOYSA-N Magnesium Chemical compound [Mg] FYYHWMGAXLPEAU-UHFFFAOYSA-N 0.000 description 1
- ZLMJMSJWJFRBEC-UHFFFAOYSA-N Potassium Chemical compound [K] ZLMJMSJWJFRBEC-UHFFFAOYSA-N 0.000 description 1
- 238000002679 ablation Methods 0.000 description 1
- 229910052782 aluminium Inorganic materials 0.000 description 1
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 1
- 238000009835 boiling Methods 0.000 description 1
- 239000011575 calcium Substances 0.000 description 1
- 229910052791 calcium Inorganic materials 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 238000005229 chemical vapour deposition Methods 0.000 description 1
- 238000005520 cutting process Methods 0.000 description 1
- 230000007123 defense Effects 0.000 description 1
- 238000000151 deposition Methods 0.000 description 1
- 230000008021 deposition Effects 0.000 description 1
- 238000007598 dipping method Methods 0.000 description 1
- 230000002708 enhancing effect Effects 0.000 description 1
- 239000010439 graphite Substances 0.000 description 1
- 229910002804 graphite Inorganic materials 0.000 description 1
- 230000005484 gravity Effects 0.000 description 1
- 239000007791 liquid phase Substances 0.000 description 1
- 238000003754 machining Methods 0.000 description 1
- 239000011777 magnesium Substances 0.000 description 1
- 229910052749 magnesium Inorganic materials 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 238000005272 metallurgy Methods 0.000 description 1
- 229910021421 monocrystalline silicon Inorganic materials 0.000 description 1
- 239000011148 porous material Substances 0.000 description 1
- 239000011591 potassium Substances 0.000 description 1
- 229910052700 potassium Inorganic materials 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 230000002035 prolonged effect Effects 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 239000004065 semiconductor Substances 0.000 description 1
- 230000035939 shock Effects 0.000 description 1
- 229910052604 silicate mineral Inorganic materials 0.000 description 1
- 229910010271 silicon carbide Inorganic materials 0.000 description 1
- 239000011734 sodium Substances 0.000 description 1
- 229910052708 sodium Inorganic materials 0.000 description 1
- 239000002904 solvent Substances 0.000 description 1
- 230000008646 thermal stress Effects 0.000 description 1
- 235000012431 wafers Nutrition 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
- C04B35/71—Ceramic products containing macroscopic reinforcing agents
- C04B35/78—Ceramic products containing macroscopic reinforcing agents containing non-metallic materials
- C04B35/80—Fibres, filaments, whiskers, platelets, or the like
- C04B35/83—Carbon fibres in a carbon matrix
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Ceramic Engineering (AREA)
- Composite Materials (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Manufacturing & Machinery (AREA)
- Materials Engineering (AREA)
- Structural Engineering (AREA)
- Organic Chemistry (AREA)
- Carbon And Carbon Compounds (AREA)
Abstract
The invention belongs to the technical field of composite materials, and particularly relates to a purification method of a carbon-carbon composite material. The purification method of the carbon-carbon composite material provided by the invention comprises the following steps: placing the carbon-carbon composite material in a purification furnace, and heating to the purification temperature; the purification temperature is 2100-2400 ℃; vacuumizing the purification furnace until the pressure in the furnace is-88.8 to-85.8 kPa, and introducing freon-argon mixed gas until the pressure in the furnace is-69.8 to-65.8 kPa; and repeating the processes of vacuumizing and introducing the freon-argon gas mixture for 60-80 times to obtain the high-purity carbon-carbon composite material. The purification method provided by the invention can effectively reduce ash content of the carbon-carbon composite material product and reduce impurities, thereby reducing pollution to other materials in application.
Description
Technical Field
The invention belongs to the technical field of composite materials, and particularly relates to a purification method of a carbon-carbon composite material.
Background
With the rapid development of the photovoltaic industry, the application of carbon-carbon composite materials is becoming wider. Meanwhile, with the development of third generation semiconductor materials, particularly large-size monocrystalline silicon carbide (SiC), large-size thick-film SiC wafers place higher demands on the physicochemical properties of chemical vapor deposition/liquid phase dip products that can be epitaxially grown at high flow rates, high quality, and high speed.
The carbon-carbon composite material has the advantages of low density, high specific gravity, ablation resistance, small thermal expansion coefficient, excellent thermal shock resistance, good friction and wear performance and the like, and is widely applied to high-tech fields such as aviation, aerospace, machinery, chemical industry, electronics, metallurgy, medical use and the like and national defense industry. The carbon-carbon composite material has chemical components after high-temperature heat treatment, carbon element higher than 99%, low density and extremely strong affinity, and the room temperature strength can be kept to 2500 ℃ and is insensitive to thermal stress. The production of the carbon-carbon composite material has the advantages of less links, material saving, manufacturing cost saving, high safety and reliability, but the ash content and impurities of the product are correspondingly increased along with the increase of the gas flow, the change of the gas source and the influence of a processing environment and a clamp after a series of deposition, dipping and machining, so that the pollution to other materials in application can be caused.
Disclosure of Invention
The invention aims to provide a purification method of a carbon-carbon composite material, which can effectively reduce ash content of the carbon-carbon composite material and reduce product impurities.
In order to achieve the purpose of the invention, the invention provides the following technical scheme:
the invention provides a purification method of a carbon-carbon composite material, which comprises the following steps:
placing the carbon-carbon composite material in a purification furnace, and heating to the purification temperature; the purification temperature is 2100-2400 ℃;
vacuumizing the purification furnace until the pressure in the furnace is-88.8 to-85.8 kPa, and introducing freon-argon mixed gas until the pressure in the furnace is-69.8 to-65.8 kPa;
and repeating the processes of vacuumizing and introducing the freon-argon gas mixture for 60-80 times to obtain the high-purity carbon-carbon composite material.
Preferably, the purifying furnace is a lower air inlet upper air extraction purifying furnace.
Preferably, the method further comprises maintaining a constant pressure after introducing the freon-argon mixture; the time for keeping the constant pressure is 3-7 min.
Preferably, the charging time of the Freon-argon gas mixture is 2-4 min.
Preferably, the flow rate of the Freon-argon mixture is 180-220 slm.
Preferably, the pressure of the freon in the freon-argon gas mixture is 0.2-0.4 MPa, and the flow rate is 40-60 slm.
Preferably, the flow rate of argon in the freon-argon mixture is 140-160 slm.
Preferably, the temperature is raised to the purification temperature and then the temperature is kept for 1 to 3 hours.
Preferably, the carbon-carbon composite material comprises one or more of a draft tube, a crucible, a heat preservation tube and a ring.
Preferably, the carbon-carbon composite material is assembled in a flat-laid manner or is assembled according to a caliber large-small ring sleeve.
The invention provides a purification method of a carbon-carbon composite material, which comprises the following steps: placing the carbon-carbon composite material in a purification furnace, and heating to the purification temperature; the purification temperature is 2100-2400 ℃; vacuumizing the purification furnace until the pressure in the furnace is-88.8 to-85.8 kPa, and introducing freon-argon mixed gas until the pressure in the furnace is-69.8 to-65.8 kPa; and repeating the processes of vacuumizing and introducing the freon-argon gas mixture for 60-80 times to obtain the high-purity carbon-carbon composite material. According to the method provided by the invention, high-temperature purification is adopted, the carbon-carbon composite material containing impurities is decomposed at high temperature, and freon and argon flow from the surface of the material, so that the material is subjected to deep extraction and scouring, impurities are separated from the material and taken away, various impurity elements and ash in the carbon-carbon composite material can be thoroughly separated along with the circulation of mixed gas under the high-temperature condition, and the highly pure carbon-carbon composite material is obtained. The purification method provided by the invention can effectively reduce ash content and impurities of the carbon-carbon composite material product, so that the pollution to other materials is reduced in application, and meanwhile, the toughness of the material can be enhanced, thereby prolonging the service life.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions of the prior art, the drawings that are needed in the embodiments will be briefly described below, it being obvious that the drawings in the following description are only some embodiments of the present invention, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.
FIG. 1 is a schematic process route of the purification method of the carbon-carbon composite material of example 1;
FIG. 2 is a schematic diagram of an assembly mode of the carbon-carbon composite material according to the invention according to the placement of the caliber-sized ring sleeve;
fig. 3 is a schematic diagram of an assembly mode of laying the carbon-carbon composite material according to the present invention.
Detailed Description
The invention provides a purification method of a carbon-carbon composite material, which comprises the following steps:
placing the carbon-carbon composite material in a purification furnace, and heating to the purification temperature; the purification temperature is 2100-2400 ℃;
vacuumizing the purification furnace until the pressure in the furnace is-88.8 to-85.8 kPa, and introducing freon-argon mixed gas until the pressure in the furnace is-69.8 to-65.8 kPa;
and repeating the processes of vacuumizing and introducing the freon-argon gas mixture for 60-80 times to obtain the high-purity carbon-carbon composite material.
In the present invention, all raw materials are commercially available products well known to those skilled in the art unless specified otherwise.
The invention puts the carbon-carbon composite material into a purifying furnace, and heats the material to the purifying temperature.
In the present invention, the diameter of the purification furnace is preferably 1100mm or more, preferably 1100 to 2000mm, more preferably 1100 to 1500mm; the height is preferably 800mm or more, preferably 800 to 1500mm, more preferably 800 to 1200mm; the purifying furnace is preferably a lower air inlet upper air extraction purifying furnace.
In the invention, in the lower air inlet upper air extraction purification furnace, heat is upwards transmitted, the temperature in the furnace is high, gas flows through the surface of a product after entering the furnace, and then quickly upwards reaches a proper range in the residence time of the surface of the product, so that the purification effect of a lower air inlet upper air extraction mode is optimal.
In the present invention, the carbon-carbon composite material preferably includes one or more of a guide cylinder, a crucible, a heat-insulating cylinder and a ring, and more preferably includes one or more of a guide cylinder, a crucible and a ring.
In the invention, the carbon-carbon composite material is preferably laid in a flat manner or is arranged according to a caliber-size ring sleeve; as shown in fig. 2, the ring sleeve placement according to the caliber is suitable for the assembly of one or more of a guide cylinder, a crucible and a heat preservation cylinder; as shown in fig. 3, the tiling is preferably suitable for ring assembly.
In the invention, the pressure maintaining test is also preferably included before the temperature is raised; and in the pressure maintaining test, the leak rate is lower than 150Pa for 30min and is qualified.
In the invention, thermocouple temperature measurement is preferably adopted below 800 ℃ in the heating process; infrared thermocouple temperature measurement is preferably adopted at the temperature of more than 800 ℃; the purification temperature is 2100 to 2400 ℃, preferably 2200 to 2300 ℃.
In the present invention, the temperature is preferably kept for 1 to 3 hours, more preferably 2 to 3 hours after the temperature is raised to the purification temperature.
In the invention, the effect of heating to the purification temperature is to open pores on the surface of the product, so that the product can be purified better; the constant temperature is used for making the temperature uniformity in the furnace chamber better.
After the temperature is raised to the purification temperature, the purification furnace is vacuumized until the pressure in the furnace is-88.8 to-85.8 kPa, and the Freon-argon mixed gas is introduced until the pressure in the furnace is-69.8 to-65.8 kPa.
In the invention, the pressure in the furnace after vacuum pumping is-88.8 to-85.8 kPa, preferably-88.8 to-86.8 kPa, and more preferably-88.8 to-87.8 kPa.
In the invention, the inflow speed of the Freon-argon gas mixture is preferably 180-220 slm, more preferably 200-220 slm; the charging time is preferably 2 to 4 minutes, more preferably 3 to 4 minutes; the pressure of the freon in the freon-argon gas mixture is preferably 0.2-0.4 MPa, more preferably 0.2-0.3 MPa; the inlet flow rate is preferably 40 to 60slm, more preferably 50 to 60slm; the inflow rate of argon in the freon-argon mixture is preferably 140-160 slm, more preferably 150-160 slm.
In the invention, the pressure in the furnace after the Freon-argon mixture gas is introduced is-69.8 to-65.8 kPa, preferably-69.8 to-66.8 kPa, and more preferably-69.8 to-67.8 kPa.
In the invention, the method also preferably comprises keeping constant pressure after introducing the freon-argon gas mixture; the time for maintaining the constant pressure is preferably 3 to 7 minutes, more preferably 4 to 6 minutes.
The invention repeatedly carries out the process of vacuumizing and introducing the freon-argon gas mixture for 60-80 times to obtain the high-purity carbon-carbon composite material.
In the present invention, the process of evacuating and introducing the freon-argon mixture is repeated 60 to 80 times, preferably 70 to 80 times.
In the invention, the Freon has higher chemical inertia and low boiling point, can be used as an extractant and a solvent, takes away impurities and ash content in and on the product deeply, is mixed with argon, plays a role in scouring the product, and can protect a thermal field and the product.
In the invention, the process of vacuumizing and introducing the freon-argon gas mixture is repeatedly carried out, and then the temperature is reduced to below 100 ℃.
According to the method provided by the invention, high-temperature purification is adopted, the carbon-carbon composite material containing impurities is decomposed at high temperature, and freon and argon flow from the surface of the material, so that the material is subjected to deep extraction and scouring, impurities are separated from the material and taken away, various impurity elements and ash in the carbon-carbon composite material can be thoroughly separated along with the circulation of mixed gas under the high-temperature condition, and the highly pure carbon-carbon composite material is obtained. The purification method provided by the invention can effectively reduce ash content of carbon-carbon composite material products, and reduce metal impurities and silicate mineral impurities of elements such as potassium, sodium, magnesium, calcium, aluminum and the like, thereby reducing pollution to other materials in application, and enhancing toughness of the materials, so that the service life is prolonged.
In order to further illustrate the present invention, the following description is given in detail of the method for purifying a carbon-carbon composite material provided by the present invention with reference to the accompanying drawings and examples, which should not be construed as limiting the scope of the present invention.
Example 1
The guide cylinder and the crucible are arranged in a lower air inlet upper air extraction purification furnace from inside to outside, a plurality of product cutting sample blocks are arranged in the purification furnace, the loading capacity is 100kg, and the specification of the purification furnace is 1100 (phi) multiplied by 800 (H) (mm);
the purification furnace is closed, pressure maintaining test is carried out, and the leak rate is lower than 150Pa for 30 min;
heating to 2200 deg.C, measuring temperature below 800 deg.C, measuring temperature above 800 deg.C by infrared thermocouple, and keeping constant temperature for 2 hr;
pumping furnace pressure limiting vacuum to-88.8 kPa, introducing two paths of gases into a furnace chamber, wherein one path of argon gas has a flow rate of 60slm, and one path of mixed gas of freon and argon gas, the freon pressure is 0.25MPa, the flow rate of the mixed gas is 60slm, the argon gas has a flow rate of 100slm, continuously introducing the gases for 3min until the furnace pressure reaches-69.8 kPa, and then keeping the pressure constant for 5min; then pumping extreme vacuum, and carrying out the next round of purification, wherein the scheme is used for purifying 80 rounds; and (5) after purification, cooling, and opening a furnace cover to discharge after cooling to below 100 ℃.
Example 2
10 phi 163 rings are laid on the bottom plate of the lower air inlet upper air extraction purification furnace, a graphite liner is placed on the outer side of the bottom plate to prolong the time for the air to flow to the rear end, the loading capacity is 100kg, and the specification of the purification furnace is 1100 (phi) multiplied by 800 (H) (mm);
the purification furnace is closed, pressure maintaining test is carried out, and the leak rate is lower than 150Pa for 30 min;
heating to 2200 deg.C, measuring temperature below 800 deg.C, measuring temperature above 800 deg.C by infrared thermocouple, and keeping constant temperature for 2 hr;
pumping furnace pressure limiting vacuum to-88.8 kPa, introducing two paths of gases into a furnace chamber, wherein one path of argon gas has a flow rate of 60slm, and one path of mixed gas of freon and argon gas, the freon pressure is 0.25MPa, the flow rate of the mixed gas is 60slm, the argon gas has a flow rate of 100slm, continuously introducing the gases for 3min until the furnace pressure reaches-69.8 kPa, and then keeping the pressure constant for 5min; then pumping extreme vacuum, and carrying out the next round of purification, wherein the scheme is used for purifying 80 rounds; and (5) after purification, cooling, and opening a furnace cover to discharge after cooling to below 100 ℃.
Test case
The ash test was performed on the purified on-furnace nuggets of example 1 and the on-furnace rings of example 2, and the test results are shown in table 1.
Table 1 ash test results data for the furnace products provided in examples 1-2
As can be seen from table 1, the purification method provided by the invention can effectively reduce ash content of the carbon-carbon composite material product, thereby reducing pollution to other materials in application; the ash content of the carbon-carbon composite material purified by the method is low, the ash content of the embodiment 1 is 180ppm, and the ash content requirement of the chemical industry is met; the ash content of example 2 was 4ppm and was suitable for use in the field of high-precision tip materials. Therefore, the purification method has better purification effect and great popularization and application value.
Although the foregoing embodiments have been described in some, but not all, embodiments of the invention, it should be understood that other embodiments may be devised in accordance with the present embodiments without departing from the spirit and scope of the invention.
Claims (10)
1. A method for purifying a carbon-carbon composite material, comprising the steps of:
placing the carbon-carbon composite material in a purification furnace, and heating to the purification temperature; the purification temperature is 2100-2400 ℃;
vacuumizing the purification furnace until the pressure in the furnace is-88.8 to-85.8 kPa, and introducing freon-argon mixed gas until the pressure in the furnace is-69.8 to-65.8 kPa;
and repeating the processes of vacuumizing and introducing the freon-argon gas mixture for 60-80 times to obtain the high-purity carbon-carbon composite material.
2. The purification method according to claim 1, wherein the purification furnace is a lower-intake upper-suction purification furnace.
3. The method of claim 1, wherein the introducing the freon-argon mixture further comprises maintaining a constant pressure; the time for keeping the constant pressure is 3-7 min.
4. The purification method according to claim 1, wherein the freon-argon mixture is introduced for 2 to 4 minutes.
5. The purification method according to claim 1, wherein the flow rate of the freon-argon mixture is 180 to 220slm.
6. The purification method according to claim 1 or 5, wherein the freon-argon mixture has a freon pressure of 0.2 to 0.4MPa and a flow rate of 40 to 60slm.
7. The purification method according to claim 1 or 5, wherein the flow rate of argon in the freon-argon mixture is 140 to 160slm.
8. The method according to claim 1, wherein the heating to the purification temperature is followed by a constant temperature for 1 to 3 hours.
9. The purification method of claim 1, wherein the carbon-carbon composite comprises one or more of a draft tube, a crucible, a hold-down tube, and a collar.
10. The method of claim 1, wherein the carbon-carbon composite material is assembled by laying flat or by looping according to caliber.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311776232.1A CN117534500A (en) | 2023-12-21 | 2023-12-21 | Purifying method of carbon-carbon composite material |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311776232.1A CN117534500A (en) | 2023-12-21 | 2023-12-21 | Purifying method of carbon-carbon composite material |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN117534500A true CN117534500A (en) | 2024-02-09 |
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|---|---|---|---|
| CN202311776232.1A Pending CN117534500A (en) | 2023-12-21 | 2023-12-21 | Purifying method of carbon-carbon composite material |
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| Country | Link |
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| CN (1) | CN117534500A (en) |
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- 2023-12-21 CN CN202311776232.1A patent/CN117534500A/en active Pending
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