CN114604866A - Method for preparing high-performance isostatic pressing graphite in short process - Google Patents
Method for preparing high-performance isostatic pressing graphite in short process Download PDFInfo
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Abstract
The invention belongs to the field of carbon product production, and provides a method for preparing high-performance isostatic pressing graphite in a short process. The method comprises the following steps: (1) preparing materials: the aggregate comprises: calcined asphalt coke, calcined petroleum coke and graphite additive; the graphite additive comprises isostatic pressing graphite, natural crystalline flake graphite or microcrystalline graphite; (2) hot mixing: adding asphalt after the aggregate is preheated, wherein the softening point of the asphalt is higher than 115 ℃, and the coking value of the asphalt is higher than 55%; (3) cold mixing: after the hot mixing is finished, discharging the hot pot paste material into a cooling pot for cold mixing to obtain a cold pot paste material; (4) grinding for the second time; (5) sieving and charging: (6) vibration and vacuum pumping: (7) isostatic pressing, forming and demoulding to obtain a green body: (8) primary roasting and graphitizing. The method provides a new production process, can overcome the defects of the prior art, and can be produced and prepared while the production period is obviously shortenedTo a bulk density higher than 1.80g/cm3And the bending resistance is higher than 45 MPa.
Description
Technical Field
The invention belongs to the field of carbon product production, and particularly relates to a method for preparing high-performance isostatic pressing graphite in a short process.
Background
The isostatic pressing graphite is a novel carbon graphite material, has the characteristics of high strength, high density, high purity, isotropy, homogeneous and compact structure and the like, is widely applied to the fields of photovoltaics, electric spark machining, metal continuous casting, chemical engineering, high-temperature furnaces, metallurgical jigs, war industry, semiconductors, nuclear energy and the like, and is a very important strategic basic material in economic development, technological progress and national defense construction.
The production of isostatic pressing graphite in China mainly takes petroleum coke or pitch coke as a main raw material and is processed by crushing, grinding, batching, kneading, flaking, secondary grinding, pre-molding, isostatic pressing, primary roasting, dipping, secondary roasting and graphitization.
The above-mentioned general production process has the following disadvantages:
(1) due to the limitation of a process line, the performance requirement on the raw coke is higher, and a product with proper performance can be produced only by the higher performance of the raw coke;
(2) the adopted kneading pot is a traditional heat-conducting oil heating kneading pot, the reamer is a separated unequal-speed sigma reamer, the heat-conducting oil heating temperature is limited and is difficult to exceed 220 ℃, so that only medium-temperature asphalt or modified asphalt with the softening point lower than 110 ℃ can be used, high-softening-point asphalt with higher service performance cannot be used, more mixing effects are realized in the kneading process due to the influence of the design pattern of the reamer, the kneading effect is very small, the full mixing and permeation of aggregate coke and binder asphalt cannot be guaranteed, the prepared paste has poor uniformity, low strength and high porosity, and the performance of a final product is influenced;
(3) in order to make up for the deficiency of the kneading process, the produced hot paste needs to be subjected to one or two times of sheet rolling treatment, namely a sheet rolling machine is used for rolling the paste into sheets with the thickness of 1-4mm under the condition of 150-200 ℃, so that the asphalt in a free state permeates into the aggregate, and because the sheet rolling machine has certain requirements on the plasticity of the incoming material, the paste cannot be normally rolled if the kneaded paste has poor plasticity, the thickness of the rolled sheet is adjusted roughly, or waste paste is generated, so that in order to ensure the normal operation of the rolled sheet, the kneading process usually needs to use a large amount of binder asphalt, and the kneading temperature and time are controlled in a lower range, which directly influences the exertion of the kneading process; meanwhile, the sheet rolling process is open operation, even if a flue gas collecting system and the like are arranged, the escape of flue gas is difficult to stop, and the working link is poor;
(4) the pre-die pressing is to put the secondarily milled powder into a metal die and press the powder into a product with a certain shape through a die press; because the pressurization of the molding press is directional, the powder can generate directional arrangement in the molding process, which has great influence on the homogeneity and isotropy of the final product; meanwhile, due to the pressurizing principle of a molding press, the product is far away from the position of a mold pressure head, the density of the product is slightly poor, the homogeneity of the whole product is greatly influenced, and the isotropy is also reduced; even if the powder is subsequently densified again through cold isostatic pressing, the problem of directional arrangement generated in the powder molding process cannot be solved; the secondary forming mode of pre-molding and then isostatic pressing can only produce middle and low-end products, and cannot meet the requirements of high-end application fields such as semiconductors, 3D hot bending glass molds, nuclear energy and the like;
(5) the product obtained by primary roasting has low performance and the volume density is usually less than 1.80g/cm if the product is directly graphitized3The rupture strength is lower than 40MPa, and the application requirement cannot be met, so that the product performance needs to be improved in a dipping mode; impregnating is to inject impregnant into a baked product to achieve the purpose of filling gaps, pitch in the gaps is converted into carbon through secondary baking, and finally graphitization is performed; because the pitch in the gap can shrink after secondary roasting, the bonding strength between the pitch and a roasted product is not high, the body density of the product is obviously improved in an impregnation mode, but the strength of the product is improved in a limited manner. Partial products with poor performance can meet the use requirement even after secondary impregnation and three times of roasting; meanwhile, the risk of qualified rate is increased by impregnation, and the product is easy to crack in the secondary roasting or graphitization process because of no permeation;
(6) due to the existence of the procedures of dipping and secondary burning, the production period of the method is as long as 6-10 months, and the method is difficult to adapt to the rapid change of the market.
Due to the defects, only middle and low-end products can be produced in China, and the application field is greatly limited.
Disclosure of Invention
Aiming at the defects in the prior art, the invention aims to provide a method for preparing high-performance isostatic pressing graphite in a short process; the method provides a new production process, can overcome the defects of the prior art, and can produce and prepare the product with the volume density higher than 1.80g/cm while remarkably shortening the production period3And the bending resistance is higher than 45 MPa.
In order to achieve the above purpose, the solution adopted by the invention is as follows:
a method for preparing high-performance isostatic pressing graphite in a short process comprises the following steps: (1) preparing materials: the aggregate comprises: 0-96% of calcined asphalt coke, calcined petroleum coke and graphite additive in percentage by mass; the true density of the calcined asphalt coke and the calcined petroleum coke is more than 1.98g/cm3(ii) a The granularity of the calcined asphalt coke, the calcined petroleum coke and the graphite additive is D50 between 6 and 16 mu m, and D95 is less than 100 mu m; the graphite additive comprises waste products of isostatic pressing graphite, natural crystalline flake graphite or microcrystalline graphite; (2) hot mixing: after the aggregate is dry-mixed and preheated to 110-200 ℃, asphalt with the temperature higher than 190 ℃ is added into a kneading pot, the mass percentage of the asphalt is 30-45%, the softening point of the asphalt is higher than 115 ℃, the coking value of the asphalt is higher than 55%, and the volatile component of the thickener in the hot pot is controlled to be 8-16%; (3) cold mixing: after the hot mixing is finished, discharging the hot pot paste material into a cooling pot for cold mixing to obtain cold pot paste material, and crushing the cold pot paste material after the cold pot paste material is cooled to below 80 ℃; (4) secondary grinding: grinding the crushed cold pot paste for the second time, wherein the granularity of the secondary powder is D50 of 15-45 mu m, and D95 is less than 200 mu m; (5) sieving and charging: sieving the secondary powder to form pressed powder, and then filling the pressed powder into a rubber mold; (6) vibration and vacuum pumping: sequentially vibrating, vacuumizing and sealing the rubber mold; (7) isostatic pressing, forming and demoulding to obtain a green body: then placing the mixture into a cold isostatic press for primary isostatic pressing, and demoulding to produce a green body after the forming is finished; (8) primary roasting and graphitization: and directly graphitizing the green body by primary roasting to obtain the isostatic pressing graphite.
Further, in a preferred embodiment of the present invention, in the step (1), the aggregate further comprises other additives; other additives include reinforcing materials such as carbon black or carbon fibers.
Further, in the preferred embodiment of the present invention, in the step (2), the electric heating kneading pot is used for the thermal mixing, the temperature range is 200-; the kneading temperature is 190-300 ℃, and the kneading time is 2.5-8 h. In the present application, an electrically heated kneading pot is used, high-performance asphalt having a softening point higher than 120 ℃ can be used, and kneading time, temperature, negative pressure and the like can be freely set without considering the single requirement of the post-process on paste plasticity. The special reamer of the kneading pot is beneficial to improving the kneading efficiency, enhancing the infiltration and permeation effects between the asphalt and the aggregate coke, and the produced paste has high strength, density, uniformity and other performances.
Further, in the preferred embodiment of the present invention, in the step (3), the reamer of the cooling pan is a constant speed crossed S-shaped reamer, and the cooling water is introduced into the pan wall and the reamer for forced cooling. The hot paste processing is carried out by adopting a cooling and kneading mode, and compared with the rolling piece, the hot paste processing device has the characteristics of high production efficiency, uniform and compact paste structure, high automation degree, friendly working environment and the like.
Further, in a preferred embodiment of the present invention, in steps (2) and (3), the volatile components are controlled by: the hot mixing pot and the cooling pot are connected with an exhaust valve to exhaust the smoke in the pot.
Further, in the preferred embodiment of the present invention, in the step (5), the mesh number of the secondary powder sieved by the sieve is not less than 35 meshes.
Further, in the preferred embodiment of the present invention, in the step (5), a steel mold is sleeved outside the rubber mold.
Further, in the preferred embodiment of the present invention, in the step (6), the vibration time is 10-200 seconds, and the frequency of the vibration table is 20-60 hz. The vibrating charging process can ensure that the powder has higher compactness before isostatic pressing.
Further, in the preferred embodiment of the present invention, in the step (7), the molding pressure is 120-. In the application, the isostatic pressing molding is adopted for one time, and compared with the secondary molding of firstly molding and then isostatic pressing, the isostatic pressing molding has the characteristics of compact product structure mean value, isotropy, high product performance and the like.
Further, in the preferred embodiment of the present invention, in step (8), the primary firing is performed by using a single furnace or a ring furnace, the green compact is placed in a firing pot or a saggar, the exterior is filled with a filler, and the graphitization is performed by using an acheson furnace or an internal thermal series graphitization furnace.
The method for preparing the high-performance isostatic pressing graphite in a short process has the beneficial effects that:
(1) by adopting the short-flow preparation method of the isostatic pressing graphite, the production period is 3-4 months, which is only half of the production period of the traditional process;
(2) the method for preparing the isostatic pressing graphite by adopting the short process has low requirement on the performance of the raw coke, and the volume density of the prepared isostatic pressing graphite is higher than 1.80g/cm even if the prepared ordinary pitch coke is adopted3And the bending resistance is higher than 45 MPa;
(3) the method for preparing the isostatic pressing graphite by adopting the short process does not need the steps of dipping and secondary roasting, can reduce the processing cost of dipping and secondary roasting, reduces the qualification rate risk of dipping and secondary roasting, reduces the potential risk of dipping on graphitization, and simultaneously saves the production period by 1-2 months.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. The examples, in which specific conditions are not specified, were conducted under conventional conditions or conditions recommended by the manufacturer. The reagents or instruments used are not indicated by the manufacturer, and are all conventional products available commercially.
The features and properties of the present invention are described in further detail below with reference to examples.
Example 1
The embodiment provides a method for preparing high-performance isostatic pressing graphite in a short process, which comprises the following steps:
(1) preparing materials: the aggregate comprises: 50% of calcined asphalt coke, 28% of calcined petroleum coke, 20% of isostatic pressing graphite waste product and 2% of carbon black; the granularity of the calcined asphalt coke, the calcined petroleum coke and the graphite additive is D50 of 13 mu m, and the granularity of the carbon black is D50 smaller than 60 nm;
(2) hot mixing: after dry mixing of aggregate, preheating to 120 ℃, adding liquid asphalt at 205 ℃ into a kneading pot, wherein the asphalt accounts for 35% of the total amount of the paste, the softening point of the asphalt is 118 ℃, the coking value of the asphalt is 58%, wet mixing is carried out for 4h, and the volatile content of the paste is 14.5%;
(3) cold mixing: after the hot mixing is finished, discharging the hot pot paste material into a cooling pot for cold mixing to obtain a cold pot paste material;
(4) secondary grinding: secondarily grinding the crushed cold pot paste into powder, wherein the particle size of the secondary powder is D50 and is 23 mu m;
(5) sieving and charging: after the secondary powder passes through a 50-mesh rotary vibration sieve, 900kg of the secondary powder is weighed and loaded into a rubber mold with the diameter phi of 1100 mm;
(6) vibration and vacuum pumping: vibrating for 60s at the frequency of 60hz by using a vibrating table, sealing the rubber sleeve, and vacuumizing for 60min until the vacuum degree reaches-0.09 MPa;
(7) isostatic pressing, forming and demoulding to obtain a green body: after vacuumizing, placing the die into a cold isostatic press for molding, keeping the highest molding pressure at 135MPa for 15min, and demolding to obtain a green body after molding;
(8) primary roasting and graphitizing: and roasting the green body by adopting a ring furnace, and graphitizing by adopting an Acheson graphitizing furnace to obtain the isostatic pressure graphite.
And (3) measuring: the volume density of the isostatic pressing graphite is 1.82g/cm3The resistivity was 13.5. mu. omega. m, and the flexural strength was 46 MPa.
Example 2
The embodiment provides a method for preparing high-performance isostatic pressing graphite in a short process, which comprises the following steps:
(1) preparing materials: the aggregate comprises: 55 mass percent of calcined asphalt coke, 40 mass percent of calcined petroleum coke and 5 mass percent of microcrystalline graphite; the granularity of the calcined petroleum coke is D50 of 12 mu m, the granularity of the calcined petroleum coke is D50 of 16 mu m, and the granularity of the microcrystalline graphite is D50 of 10 mu m;
(2) hot mixing: after dry mixing of aggregate, preheating to 140 ℃, adding 220 ℃ liquid asphalt in a kneading pot, wherein the asphalt accounts for 36% of the total amount of the paste, the softening point of the asphalt is 122 ℃, the coking value of the asphalt is 60%, wet mixing is carried out for 5.5h, and the volatile content of the paste is 14%;
(3) cold mixing: after the hot mixing is finished, discharging the hot pot paste material into a cooling pot for cold mixing to obtain a cold pot paste material;
(4) and (3) secondary grinding: secondarily grinding the crushed cold pot paste into powder, wherein the particle size of the secondary powder is D50 and is 33 mu m;
(5) sieving and charging: after the secondary powder passes through a 75-mesh rotary vibration sieve, 800kg of the secondary powder is weighed and loaded into a rubber mold with the diameter phi of 900 mm;
(6) vibration and vacuum pumping: vibrating for 120s at 45hz by using a vibrating table, sealing the rubber sleeve, and vacuumizing for 80min until the vacuum degree reaches-0.092 MPa;
(7) isostatic pressing, forming and demoulding to obtain a green body: after the vacuumizing is finished, the die is placed into a cold isostatic press for forming, the highest forming pressure is 145MPa, the pressure is maintained for 12min, and demoulding is carried out after the forming is finished to obtain a green body;
(8) primary roasting and graphitization: and roasting the green body by using a ring furnace, and graphitizing by using an Acheson graphitizing furnace to obtain the isostatic pressing graphite.
And (3) measuring: volume density of isostatic pressing graphite 1.83g/cm3Resistivity of 12.5 mu omega m and breaking strength of 48 MPa.
Example 3
The embodiment provides a method for preparing high-performance isostatic pressing graphite in a short process, which comprises the following steps:
(1) preparing materials: the aggregate comprises: 35% of calcined asphalt coke, 50% of calcined petroleum coke and 15% of microcrystalline graphite by mass; the granularity of the calcined petroleum coke is D50 being 8 μm, the granularity of the calcined petroleum coke is D50 being 12 μm, and the granularity of the microcrystalline graphite is D50 being 8 μm;
(2) hot mixing: after dry mixing of aggregate, preheating to 160 ℃, adding 230 ℃ liquid asphalt in a kneading pot, wherein the asphalt accounts for 35% of the total amount of the paste, the softening point of the asphalt is 130 ℃, the coking value of the asphalt is 62%, wet mixing is carried out for 3.5h, and the volatile content of the paste is 13%;
(3) cold mixing: after the hot mixing is finished, discharging the hot pot paste material into a cooling pot, and performing cold mixing to obtain a cold pot paste material;
(4) and (3) secondary grinding: secondarily grinding the crushed cold pot paste into powder, wherein the particle size of the secondary powder is D50 and is 28 mu m;
(5) sieving and charging: after the secondary powder passes through a rotary vibration sieve of 100 meshes, 600kg of the secondary powder is weighed and loaded into a rubber mold with the diameter phi of 600 mm;
(6) vibration and vacuum pumping: vibrating for 80s at the frequency of 25hz by using a vibrating table, sealing the rubber sleeve, and vacuumizing for 60min until the vacuum degree reaches-0.09 MPa;
(7) isostatic pressing, forming and demoulding to obtain a green body: after vacuumizing, placing the die into a cold isostatic press for molding, keeping the highest molding pressure at 125 MPa for 10min, and demolding to obtain a green body after molding is finished;
(8) primary roasting and graphitization: and roasting the green body by adopting a ring furnace, and graphitizing by adopting an Acheson graphitizing furnace to obtain the isostatic pressure graphite.
And (3) measuring: the volume density of the isostatic pressing graphite is 1.86g/cm3The resistivity was 12.5. mu. omega. m, and the flexural strength was 52 MPa.
Example 4
The embodiment provides a method for preparing high-performance isostatic pressing graphite in a short process, which comprises the following steps:
(1) preparing materials: the aggregate comprises: 96% of calcined asphalt coke, 2% of calcined petroleum coke and 2% of natural crystalline flake graphite by mass percentage; the granularity of the calcined asphalt coke is D50 of 6 mu m, the granularity of the calcined petroleum coke is D50 of 16 mu m, and the granularity of the natural crystalline flake graphite is D50 of 8 mu m;
(2) hot mixing: after dry mixing of aggregate, preheating to 110 ℃, adding 195 ℃ liquid asphalt into a kneading pot, wherein the asphalt accounts for 30% of the total amount of the paste, the softening point of the asphalt is 116 ℃, the coking value of the asphalt is 56%, wet mixing is carried out for 2.5h, and the volatile content of the paste is 8%;
(3) cold mixing: after the hot mixing is finished, discharging the hot pot paste material into a cooling pot for cold mixing to obtain a cold pot paste material;
(4) secondary grinding: secondarily grinding the crushed cold pot paste into powder, wherein the particle size of the secondary powder is D50 and is 15 mu m;
(5) sieving and charging: after the secondary powder passes through a 35-mesh rotary vibration sieve, weighing 1000kg of the secondary powder and putting the secondary powder into a rubber mold with the diameter phi of 1200 mm;
(6) vibration and vacuum pumping: vibrating for 10s at the frequency of 60hz by using a vibrating table, sealing the rubber sleeve, and vacuumizing for 60min until the vacuum degree reaches-0.09 MPa;
(7) isostatic pressing, forming and demoulding to obtain a green body: after the vacuumizing is finished, the die is placed into a cold isostatic press for forming, the highest forming pressure is 120MPa, the pressure is maintained for 40min, and demoulding is carried out after the forming is finished to obtain a green body;
(8) primary roasting and graphitizing: and roasting the green body by adopting a ring furnace, and graphitizing by adopting an Acheson graphitizing furnace to obtain the isostatic pressure graphite.
And (3) measuring: the volume density of the isostatic pressing graphite is 1.81g/cm3The resistivity was 13.8. mu. omega. m, and the flexural strength was 46 MPa.
Example 5
The embodiment provides a method for preparing high-performance isostatic pressing graphite in a short process, which comprises the following steps:
(1) preparing materials: the aggregate comprises: 2% of calcined asphalt coke, 96% of calcined petroleum coke and 2% of microcrystalline graphite by mass; the granularity of the calcined asphalt coke is D50 being 16 mu m, the granularity of the calcined petroleum coke is D50 being 6 mu m, and the granularity of the microcrystalline graphite is D50 being 6 mu m;
(2) hot mixing: after dry mixing of aggregate, preheating to 200 ℃, adding liquid asphalt at 240 ℃ into a kneading pot, wherein the asphalt accounts for 45% of the total amount of the paste, the softening point of the asphalt is 135 ℃, the coking value of the asphalt is 65%, and wet mixing is carried out for 8h, wherein the volatile content of the paste is 16%;
(3) cold mixing: after the hot mixing is finished, discharging the hot pot paste material into a cooling pot for cold mixing to obtain a cold pot paste material;
(4) and (3) secondary grinding: secondarily grinding the crushed cold pot paste into powder, wherein the particle size of the secondary powder is D50 and is 45 mu m;
(5) sieving and charging: after the secondary powder passes through a 120-mesh rotary vibration sieve, 500kg of the secondary powder is weighed and loaded into a rubber mold with the diameter phi of 500 mm;
(6) vibration and vacuum pumping: vibrating for 200s at 20hz by using a vibrating table, sealing the rubber sleeve, and vacuumizing for 60min until the vacuum degree reaches-0.09 MPa;
(7) isostatic pressing, forming and demoulding to obtain a green body: after the vacuumizing is finished, the die is placed into a cold isostatic press for forming, the highest forming pressure is 180MPa, the pressure is maintained for 5min, and demoulding is carried out after the forming is finished to obtain a green body;
(8) primary roasting and graphitizing: and roasting the green body by using a ring furnace, and graphitizing by using an Acheson graphitizing furnace to obtain the isostatic pressing graphite.
And (3) measuring: the volume density of the isostatic pressing graphite is 1.85g/cm3The resistivity was 13.1. mu. omega. m, and the flexural strength was 47 MPa.
In conclusion, the invention provides a method for preparing high-performance isostatic pressing graphite in a short process, the method provides a novel production process, the defects of the existing process can be overcome, the production period can be obviously shortened, and meanwhile, the volume density of the prepared high-performance isostatic pressing graphite is higher than 1.80g/cm even if common asphalt coke is adopted3And the bending resistance is higher than 45 MPa.
The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (10)
1. A method for preparing high-performance isostatic pressing graphite in a short process is characterized by comprising the following steps: the method comprises the following steps:
(1) preparing materials: the aggregate comprises: 0-96% of calcined asphalt coke, calcined petroleum coke and graphite additive in percentage by mass; the particle size of the calcined asphalt coke, the calcined petroleum coke and the graphite additive is D50 between 6 and 16 mu m, and D95 is less than 100 mu m; the graphite additive comprises waste products of the isostatic pressing graphite, natural crystalline flake graphite or microcrystalline graphite;
(2) hot mixing: after the aggregate is dry-mixed and preheated to 110-200 ℃, adding asphalt with the temperature higher than 190 ℃ into a kneading pot, wherein the mass percent of the asphalt is 30-45%, the softening point of the asphalt is higher than 115 ℃, the coking value of the asphalt is higher than 55%, and the volatile component of the hot pot paste is controlled to be 8-16%;
(3) cold mixing: after the hot mixing is finished, discharging the hot pot paste material into a cooling pot for cold mixing to obtain a cold pot paste material, and crushing the cold pot paste material after the cold pot paste material is cooled to below 80 ℃;
(4) secondary grinding: secondarily grinding the crushed cold pot paste into powder, wherein the particle size of the secondary powder is D50 and D95 is smaller than 200 mu m, and the particle size of the secondary powder is 15-45 mu m;
(5) sieving and charging: sieving the secondary powder to form pressed powder, and then filling the pressed powder into a rubber mold;
(6) vibration and vacuum pumping: sequentially vibrating, vacuumizing and sealing the rubber mold;
(7) isostatic pressing, forming and demoulding to obtain a green body: then placing the mixture into a cold isostatic press for primary isostatic pressing, and demoulding to produce a green body after the forming is finished;
(8) primary roasting and graphitizing: and directly graphitizing the green body by primary roasting to obtain the isostatic pressing graphite.
2. The short-run method for preparing high-performance isostatic graphite according to claim 1, wherein: in the step (1), the aggregate also comprises other additives; the other additives include carbon black or carbon fiber.
3. The short-run method for preparing high-performance isostatic graphite according to claim 1, wherein: in the step (2), an electric heating kneading pot is adopted for hot mixing, the temperature range is 200-500 ℃, and the reamer of the kneading pot is a constant-speed intersected S-shaped reamer; the kneading temperature is 190-300 ℃, and the kneading time is 2.5-8 h.
4. The short-run method for preparing high-performance isostatic graphite according to claim 1, wherein: in the step (3), the reamer of the cooling pot is a constant-speed intersected S-shaped reamer, and cooling water is introduced into the pot wall and the reamer to carry out forced cooling.
5. The short-run method for preparing high-performance isostatic graphite according to claim 1, wherein: in the steps (2) and (3), the volatile components are controlled by: and connecting the hot mixing pot and the cooling pot with an exhaust valve to exhaust the smoke in the pot.
6. The short-run method for preparing high-performance isostatic graphite according to claim 1, wherein: in the step (5), the mesh number of the screen for sieving the secondary powder is not less than 35 meshes.
7. The short process preparation of isostatic graphite according to claim 1, wherein: in the step (5), a steel mould is sleeved outside the rubber mould.
8. The short-run method for preparing high-performance isostatic graphite according to claim 1, wherein: in the step (6), the vibration time is 10-200 seconds, and the frequency of the vibration table is 20-60 hz.
9. The short-process preparation method of isostatic graphite according to claim 1, wherein: in the step (7), the molding pressure is 120-.
10. The short-run method for preparing high-performance isostatic graphite according to claim 1, wherein: in the step (8), a monomer furnace or a ring furnace is adopted for primary roasting, the green body is placed into a burning tank or a saggar, the filler is filled outside the green body, and an Acheson furnace or an internal heating serial graphitization furnace is adopted for graphitization.
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| CN115353390A (en) * | 2022-08-09 | 2022-11-18 | 自贡东新电碳有限责任公司 | Preparation method of high-density carbon graphite composite material |
| CN116332650A (en) * | 2023-03-30 | 2023-06-27 | 青岛正望新材料股份有限公司 | Short-process near-net-shape manufacturing method of graphite product |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN107522196A (en) * | 2017-08-28 | 2017-12-29 | 成都炭素有限责任公司 | A kind of superhard isostatic pressing formed graphite and preparation method thereof |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN107522196A (en) * | 2017-08-28 | 2017-12-29 | 成都炭素有限责任公司 | A kind of superhard isostatic pressing formed graphite and preparation method thereof |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115353390A (en) * | 2022-08-09 | 2022-11-18 | 自贡东新电碳有限责任公司 | Preparation method of high-density carbon graphite composite material |
| CN116332650A (en) * | 2023-03-30 | 2023-06-27 | 青岛正望新材料股份有限公司 | Short-process near-net-shape manufacturing method of graphite product |
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