CN115108833A

CN115108833A - Continuous casting graphite material and preparation method thereof

Info

Publication number: CN115108833A
Application number: CN202210926461.6A
Authority: CN
Inventors: 朱约辉; 廖仕明
Original assignee: Hubei Southeast Jiate Carbon New Material Co ltd
Current assignee: Hubei Southeast Jiate Carbon New Material Co ltd
Priority date: 2022-08-03
Filing date: 2022-08-03
Publication date: 2022-09-27
Anticipated expiration: 2042-08-03
Also published as: CN115108833B

Abstract

The invention discloses continuous casting graphite and a preparation method thereof, belonging to the technical field of material science. The continuous casting graphite material prepared by the method has high wear resistance, good sealing performance, good heat conduction and good physical, mechanical and chemical properties in the using process.

Description

Continuous casting graphite material and preparation method thereof

Technical Field

The invention relates to a graphite material and a preparation method thereof, in particular to continuous casting graphite and a preparation method thereof, and belongs to the field of special graphite.

Background

Continuous casting graphite (graphite for continuous casting mold) refers to a graphite product used in a continuous casting mold. The continuous casting technology is a new technology for directly forming materials by molten metal through a continuous casting crystallizer. Because it is directly finished without rolling, the secondary heating of metal is avoided, so that a large amount of energy can be saved.

The continuous casting graphite is prepared from carbonaceous raw materials (petroleum coke, pitch coke, coal pitch and the like) through a series of production process, wherein the compression molding process can respectively adopt a cold mould pressing molding process or a cold isostatic pressing molding process. The advanced high-tonnage cold isostatic pressing process is adopted, so that the continuous casting graphite with uniform, compact and high-strength texture can be produced. The addition of surface coating technology can prolong the service life of graphite crystallizer, improve the quality of continuous casting metal surface and raise the speed of continuous casting process.

In recent years, copper pipe molding continuous casting graphite is mainly suitable for copper drawing molding, more than 100% of high-end domestic continuous casting graphite still adopts imported materials, and products for replacing imported materials do not exist at home at present, but compared with similar products at home, the copper pipe molding continuous casting graphite has certain defects in the aspects of solving the problems of the stability of wear resistance, internal structure and friction coefficient of continuous casting graphite, particularly the stability of the internal structure and the wear resistance under the operation condition of copper drawing and the like. At present, the main material combination of petroleum coke and asphalt binder is generally adopted.

At present, continuous casting graphite is mainly researched on the basis of mould pressing, raw materials are limited in pitch coke series, the preparation method generally adopts the process flows of kneading, grinding, mould pressing, roasting, dipping and graphitizing, and the existing preparation method has the following technical defects: the operation process steps are complicated and complex, so that the preparation production time is long, the production cost is high, and the production efficiency is low; and the quality of the prepared product is unstable, and the product performance is poor.

Disclosure of Invention

The invention aims at solving the technical problems in the prior continuous casting graphite technology and provides copper pipe molding continuous casting graphite and a preparation method thereof.

In order to achieve the object of the present invention, in one aspect, the present invention provides a method for preparing a continuous casting graphite material, comprising the steps of:

1) adding continuous casting graphite raw materials of pitch coke, petroleum coke, artificial graphite and spray carbon black into a kneading pot with the temperature kept between 90 and 100 ℃ for first kneading treatment; uniformly mixing to prepare an asphalt coke-petroleum coke-graphite-carbon black mixture; then adding the raw materials of sulfur and molybdenum disulfide, heating and raising the temperature, and carrying out second kneading treatment; after uniform mixing, heating to 160-200 ℃, adding modified asphalt under the condition of keeping the temperature in the kneading pot at 160-200 ℃ for third kneading treatment to obtain a kneaded mixture;

2) crushing the kneaded mixture, and sieving to obtain a mixed crushed material;

3) grinding the mixed crushed material, and sieving to obtain mixed micropowder material;

4) placing the mixed micro powder material in a die of a press, and pressing to prepare a pressed blank;

5) placing the pressed blank in an isostatic pressing machine, and carrying out forming treatment to obtain a formed blank;

6) placing the formed blank in a roasting kiln, and carrying out first sintering treatment to prepare a first sintered blank;

7) putting the first sintered blank into an impregnation tank for vacuumizing until the vacuum degree in the impregnation tank is lower than 5torr (gauge pressure, preferably 3-5torr), adding molten medium-temperature asphalt into the impregnation tank, and then performing pressurization-impregnation treatment to obtain an impregnated blank;

8) placing the impregnated blank in a roasting kiln, and performing second sintering treatment to obtain a second sintered blank;

9) and placing the second sintering blank in a graphitization furnace for graphitization treatment to obtain the continuous casting graphite.

The raw materials of the continuous casting graphite comprise asphalt coke, petroleum coke, artificial graphite, spray carbon black, sulfur, molybdenum disulfide, modified asphalt and medium temperature asphalt, wherein the raw materials comprise the following components in parts by weight:

artificial graphite: the granularity is-300 meshes, the carbon content is more than or equal to 99 percent, and the ash content is less than or equal to 1 percent; the artificial graphite has the characteristics of light weight, good electric conduction, heat conduction and lubricating properties, excellent machining performance and the like.

Modifying asphalt: the tar distillation residual liquid is 54-56% of tar, and is composed of aromatic compounds with more than three rings, heterocyclic compounds containing oxygen, nitrogen and sulfur and a small amount of high molecular carbon substances. Modifying asphalt: softening point: toluene insolubles at 105-112 ℃: 25-28%, quinoline insolubles: 6 to 12 percent; coking refers to: not less than 58%, volatile components: 50 to 55 percent. And plays a role as a binder in the material.

Pitch coke: the granularity is-300 meshes, the water content is less than or equal to 1 percent, the ash content is less than or equal to 1 percent, and the true density is more than or equal to 1.98g/cm ³ . Low-sulfur cooked coke blocks are adopted. The asphalt coke has the characteristics of wear resistance, stable friction coefficient and the like, so that the wear resistance of the material and the strength of the whole material can be improved by adding the asphalt coke, and the molten copper can not react with the asphalt coke in the drawing and forming process.

Petroleum coke: the granularity is-300 meshes, the water content is less than or equal to 1 percent, and the ash content is less than or equal to 1 percent. Low-sulfur cooked coke blocks are adopted. The petroleum coke has the characteristics of heat resistance, wear resistance, stable friction coefficient, low loss and the like, so the addition of the petroleum coke can improve the heat resistance and wear resistance of the material, improve the friction coefficient of the material and reduce the loss of the material.

Spray carbon black (i.e., powdered spray carbon black): the mesh number is-300 meshes, and the main purposes are to increase the wear resistance of the product and fill the pores in the product so as to prevent copper water from diffusing into the graphite during use to cause cracking of the continuous casting graphite.

Sulfur: the mesh number is-200 meshes, and the sulfur is mainly used for improving the carbon residue rate of the product and reducing the ash content.

Molybdenum disulfide: the mesh number is-2000 meshes, so that the lubricating oil has good lubricity and good wear resistance, can play a role in increasing friction at high temperature, and the wear resistance of the continuous casting graphite material is improved by adding molybdenum disulfide; and the molybdenum disulfide has high melting point, and is suitable for mechanical working states of high temperature, high pressure, high rotating speed and high load.

Particularly, the first kneading treatment temperature in the step 1) is 90-100 ℃; the second kneading treatment temperature is 160-180 ℃; the third kneading temperature was 160-.

In particular, the first kneading treatment temperature in step 1) is preferably 95 ℃; the first kneading treatment is carried out for at least 30min, preferably 30-60 min; the second kneading treatment temperature is preferably 170 ℃; the second kneading treatment is carried out for 30-50min, preferably 40 min; the third kneading treatment temperature is preferably 190 ℃; the third kneading treatment is carried out for 120-150min, preferably for 130 min.

Particularly, the method further comprises the step of stopping heating after the third kneading treatment is carried out for 120-150min, pouring the mixture into a material box after the temperature in the kneading pot is reduced to be below 100 ℃, and continuously cooling to the room temperature to obtain the kneaded mixture.

In particular, the kneader is heated until the temperature in the kneader reaches and is maintained at 90 to 100 ℃ before the pitch coke, petroleum coke, artificial graphite and spray carbon black are added into the kneader.

Particularly, the modified asphalt is molten modified asphalt, namely the modified asphalt is placed in an asphalt melting tank and heated to 160-200 ℃ so that the modified asphalt is melted into liquid; then adding the mixture into a kneading pot, and carrying out third kneading treatment.

Specifically, before the raw materials of pitch coke, petroleum coke, artificial graphite and spray carbon black are added in the step 1), the kneading pot is heated so that the temperature of the kneading pot reaches and is maintained at 90 to 100 ℃ (preferably 95 ℃), and then the raw materials are added to carry out the first kneading treatment.

Wherein the granularity of the mixed crushed material in the step 2) is less than or equal to 40 meshes.

Particularly, the kneaded mixture is placed in a crusher in the step 2) to be subjected to crushing treatment; the sieving treatment refers to sieving with a 30-50 mesh sieve after crushing, and the sieved material is the material passing through the sieve, namely the mixed crushed material.

Particularly, the mixture is sieved by a 40-mesh sieve to obtain a mixed crushed material with the granularity less than or equal to 40 meshes.

Wherein, the mixed crushed material is put into a pulverizer in the step 3) for pulverizing treatment.

In particular, the particle size of the mixed micropowder is 15-18 μm.

Wherein the pressure of the pressing treatment in the step 4) is 2-6MPa, preferably 2-5 MPa; the pressing treatment time is 25-40 min.

Particularly, before the pressing treatment, the method also comprises the step of putting the material micro powder into a V-shaped mixing pot for mixing for 2-4h, preferably 3 h.

In particular, the press is a model 1250t press.

Wherein the molding treatment time in the step 5) is 0.5-1h, preferably 0.8 h; the relative pressure of the molding treatment is 180-200MPa, preferably 190-200 MPa.

Particularly, the molding blank is placed in an isostatic pressing machine to carry out the molding treatment, wherein the molding pressure is 180-; the molding treatment time is 0.5 to 1 hour, preferably 0.8 hour.

Wherein, the first sintering temperature in the step 6) is 900-1000 ℃, preferably 900-950 ℃; the first sintering treatment time is 25 to 30 days, preferably 25 days.

Wherein the relative pressure of the pressure-impregnation treatment in the step 7) is 2-3.5MP, preferably 2-3.0 MPa; the pressure-impregnation treatment time is 8 to 10 hours, preferably 9 hours.

In particular, the pressure-impregnation treatment temperature is 180-.

In particular, the molten medium-temperature asphalt is prepared according to the following method: and (3) placing the medium-temperature asphalt into an asphalt melting tank, heating to 190 ℃ at 180 ℃, adding the medium-temperature asphalt for at least 6 hours, and melting the medium-temperature asphalt into liquid to obtain the asphalt.

In particular, the method also comprises the step of airing the impregnated blank at room temperature, wherein the airing time is at least 24 hours.

Wherein the temperature of the second sintering treatment in the step 8) is 900-1000 ℃, preferably 900-950 ℃; the second sintering time is 35 to 45 days, preferably 40 days.

In particular, the temperature of the graphitization treatment in the step 9) is 2700-; the graphitization treatment time is 600-650h, and preferably 600 h.

In another aspect, the present invention provides a continuous cast graphite material prepared according to any of the above methods.

Compared with the prior art, the continuous casting graphite has the following advantages:

1. in the preparation process of the continuous casting graphite, the operation process conditions are stable, the controllability is high, the equipment is stable, the raw material mixing uniformity is high, and the product quality is high;

2. the internal structure of the continuous casting graphite product prepared by the method is more uniform, and the product is simultaneously pressed and molded in different directions around the product through isostatic pressing, so that the internal structure compactness of the product is improved, and the density uniformity of the product is improved;

3. the roasting treatment of the method adopts a car bottom type roasting process instead of a ring furnace roasting mode, the temperature in the roasting treatment process is uniform, the temperature difference in the furnace is +/-10 ℃, circulating air is provided for circulation, the temperature in the product roasting process is uniform, and the product defects caused by stress due to the temperature difference are avoided;

4. the continuous casting graphite prepared by the method has good wear resistance and sealing performance; good heat conduction and good physical, mechanical and chemical properties.

5. The method of the invention is improved aiming at the prior process, mainly reduces the process flow, increases the isostatic pressing procedure, and mainly increases the combination of product density and granularity, so that the process parameter requirement can be met by one-time roasting, the process requirement can be met by one-time soaking, the time is shortened, the cost is reduced, and the foundation is made for later process improvement.

Drawings

FIG. 1 is a process flow diagram of the continuous casting graphite preparation method of the present invention.

Detailed Description

The invention will be further described with reference to specific embodiments, and the advantages and features of the invention will become apparent as the description proceeds. These examples are illustrative only and do not limit the scope of the present invention in any way. It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention, and that such changes and modifications may be made without departing from the spirit and scope of the invention.

Example 1

1. Preparing materials (kg) according to the following weight ratio:

wherein the modified asphalt has a softening point: 105 to 112 ℃; toluene insolubles: 25 to 28 percent; quinoline insoluble matter: 6 to 12 percent; coking refers to: not less than 58%, volatile components: 50-55 percent;

the particle size of the asphalt coke is-300 meshes, the water content is less than or equal to 1 percent, the ash content is less than or equal to 1 percent, and the true density is more than or equal to 1.98g/cm ³ ；

The granularity of the petroleum coke is-300 meshes, the water content is less than or equal to 1 percent, and the ash content is less than or equal to 1 percent;

spraying carbon black: the mesh number is-300 meshes; sulfur: the mesh number is-200 meshes;

molybdenum disulfide: the mesh number is-2000 meshes

2. Starting a kneading pot, heating to raise the temperature, adding raw materials of asphalt coke, petroleum coke, artificial graphite and spray carbon black into the kneading pot when the temperature in the kneading pot reaches and is kept at 95 ℃ (usually 90-100 ℃), carrying out primary kneading treatment, and mixing for 30min (usually at least 30min, preferably 30-60min) to prepare an asphalt coke-petroleum coke-graphite-carbon black mixture;

in the embodiment, the temperature for adding the raw materials of the pitch coke, the petroleum coke, the artificial graphite and the spray carbon black is 95 ℃ for example, and other temperatures are 90-100 ℃; the first kneading temperature is 95 ℃ for example, and other temperatures are 90-100 ℃; the mixing time is 30min, and other times are more than 30 min.

3. Adding sulfur and molybdenum disulfide into the asphalt coke-petroleum coke-graphite-carbon black mixture in the kneading pot, continuously heating until the temperature in the kneading pot is raised to 170 ℃ (usually 160-;

in this embodiment, the temperature for adding the raw materials of sulfur and molybdenum disulfide is 170 ℃, and other temperatures are 160 ℃ and 180 ℃; the second kneading temperature is 170 ℃, and other temperatures are 160 ℃ and 180 ℃; the second kneading time is 40min, and the other times are 30-50 min.

In the invention, the raw materials of the continuous casting graphite are added separately and mixed uniformly, the raw material with high dosage is added and mixed first, and the raw material with low dosage is added after the raw material with high dosage is mixed uniformly, so that the uneven mixing of the materials can be prevented; the raw material sulfur is added in the subsequent high-temperature stage, so that sulfur bonds can be formed in the carbon material by the sulfur, the wetting and the coating of the binder on the carbon material are facilitated, the sulfur can exist in the form of functional groups such as carbon groups and the like, and the carbon formation can be facilitated to a certain extent; after the sulfur is added, the temperature is raised again, so that the sulfur content in the sulfur is volatilized, the combination with the raw materials is promoted, and the carbonization is facilitated; in addition, the temperature is increased again, which is beneficial to the emission of volatile components and meets the process requirements.

4. After the second kneading for 40min, heating to 190 ℃ (usually 160-;

in this embodiment, the temperature for adding the raw material modified asphalt is 190 ℃, and other temperatures are 160 ℃ and 200 ℃; the third kneading temperature is 190 ℃, and other temperatures are 160 ℃ and 200 ℃; the third kneading time is 130min for example, and the other times 120-150min are all applicable.

The modified asphalt is subjected to melting treatment to remove impurities in the modified asphalt, so that the impurities in the modified asphalt are prevented from being mixed into raw materials to cause cracking of a prepared product; and the modified asphalt is favorable for being mixed with the raw materials after being melted and is uniformly mixed.

5. Putting the kneaded mixture cooled to room temperature in the material box into a crusher for crushing treatment, and sieving with a 40-mesh sieve (usually 30-50-mesh sieve) to obtain a mixed crushed material;

in the invention, the 40-mesh sieve is taken as an example for sieving after crushing treatment, and other 30-50-mesh sieves are all suitable.

The sieving mainly comprises the step of re-crushing the sieved particles, because coarse particles cannot be directly fed into the superfine pulverizer, and the particle size of the particles sieved by a 40-mesh sieve is suitable for the next superfine pulverizer treatment process.

6. Placing the mixed crushed material in an ultramicro powder mill, grinding the mixed crushed material into powder, and sieving the powder to obtain mixed micropowder material, wherein the particle size of the mixed micropowder material is 15-18 mu m;

7. putting the mixed micropowder into a V-shaped mixing pot, mixing for 3h (usually 2-4h), and then filling the mixed micropowder into a special material bag;

before the compression treatment, the mixing treatment time is 3 hours, and other mixing time is 2-4 hours.

8. Putting the mixed micro powder into a die of a press (model 1250t), and performing pressing treatment to prepare a pressed blank, wherein the absolute pressure of the pressing treatment is 4MPa (usually 2-6 MPa); the pressing treatment time is 30min (usually 25-40 min);

9. placing the pressed blank in an isostatic pressing machine, and carrying out forming treatment to obtain a formed blank; wherein the absolute pressure of the molding treatment is 190MPa (typically 180-200 MPa); the molding treatment time is 1h (usually 0.5-1 h);

in the invention, the absolute pressure of the pressing treatment is taken as 4MPa, and other pressures are all suitable for 2-6 MPa; the pressing time is 30min for example, and other pressing times of 25-40min are applicable. The absolute pressure of the molding treatment is 190MPa, and other pressures of 180-200MPa are all applicable; the molding treatment time is 1 hour, and other times are all applicable within 0.5-1 hour.

10. Placing the formed blank in a roasting kiln, and carrying out first sintering treatment to prepare a first sintered blank, wherein the temperature of the first sintering treatment is 950 ℃ (usually 900-1000 ℃); the first sintering treatment time is 25 days (usually 25-30 days);

in the embodiment of the invention, the first sintering temperature is 950 ℃, and other temperatures are 900 ℃ and 1000 ℃; the sintering time is for example 25 days, and other sintering times such as 25-30 days are suitable.

In the first sintering process, volatile matters generated by roasting are discharged, so that the structure of the graphite is changed in the high-temperature process, and sulfur and other volatile matters generated after the asphalt is roasted are combined with other materials to meet the process requirements.

11. Putting the first sintered blank into an impregnation tank, vacuumizing the impregnation tank until the vacuum degree in the impregnation tank reaches 4torr (gauge pressure, usually 3-5torr), adding medium-temperature asphalt liquid with the temperature kept at 185 ℃ (usually 180-; and pressurizing the impregnation tank until the relative pressure in the impregnation pipe reaches and is maintained at 3MPa (usually 2-3.5MPa), and performing pressure-impregnation treatment on the first sintered blank in the impregnation tank, wherein the pressure-impregnation treatment temperature is 185 ℃ (usually 180 DEG and 190 ℃, and the pressure-impregnation treatment time is 9h (usually 8-10h) to obtain the impregnated blank, wherein the molten medium-temperature asphalt liquid is obtained by putting the medium-temperature asphalt into an asphalt melting tank and heating to 180 DEG and 190 ℃ until the asphalt is melted into liquid, and the melting time is about 6 h.

In the embodiment of the invention, the vacuum degree of the vacuum pumping treatment in the impregnation tank is 4torr gauge pressure as an example, and other vacuum degrees are 3-5 torr; the relative pressure of the pressure-impregnation treatment is, for example, 3MPa, and other relative pressures such as 2 to 3.5MPa are applicable; the pressure-impregnation treatment time is 9 hours as an example, and other impregnation times such as 8-10 hours are applicable; the pressure impregnation temperature is 185 ℃ for example, and other temperatures 180 ℃ and 190 ℃ are suitable.

The invention carries out dipping treatment, which mainly increases the density, the breaking strength, the compression strength and the hardness index of the product so as to reach the required index standard; the vacuum pumping treatment is mainly to pump oxygen in the product to make the pitch dipping liquid easily enter the pores of the product structure in the pressurizing process to fill the pores, so as to achieve the weight gain rate required by the process.

12. Taking out the impregnated blank, airing at room temperature for 24h (airing for at least 24h, usually 24-36h), placing in a roasting kiln, and performing second sintering treatment to obtain a second sintered blank, wherein the second sintering treatment temperature is 950 ℃ (usually 900-1000 ℃); the second sintering treatment time is 40 days (usually 35-45 days);

in the embodiment of the invention, the second sintering temperature is 950 ℃, and other temperatures are 900 ℃ and 1000 ℃; the second sintering time is, for example, 40 days, and other sintering times, such as 35-45 days, are suitable.

The second sintering process removes the ash of the medium temperature pitch used in the impregnation process, and the pitch combines with the molecules in the original product.

The invention carries out the first and second sintering treatments to reduce ash content and volatile components of the raw materials, improve density and strength, reduce shrinkage of products, improve conductivity (by powder specific resistance), remove moisture in the raw materials (less than 0.3 percent), reduce oxygen, nitrogen and sulfur heteroatoms and facilitate graphitization.

13. Placing the second sintered blank into a graphitization furnace, and performing graphitization treatment to prepare continuous casting graphite, wherein the graphitization treatment temperature is 2750 ℃ (usually 2700-; the graphitization treatment time is 600h (usually 600-650 h).

The graphitization treatment on the second sintering blank is carried out by adopting a conventional graphitization method and an operation process in the field, and the graphitization treatment method and equipment in the continuous casting graphite preparation process in the field are all suitable for the invention. Graphitization treatment is used for improving the electrical conductivity and the thermal conductivity of the material; the thermal and chemical stability of the material is improved, such as oxidation resistance, corrosion resistance, reduction of thermal expansion coefficient and the like; impurities are removed, and the purity is improved; the ash content is reduced by 70%; the hardness is reduced, and the precision machining of the product is facilitated.

Example 2

The same procedure as in example 1 was repeated except that the following ingredients (kg) were prepared,

example 3

The same procedure as in example 1 was repeated except that the following ingredients (kg) were prepared in the following weight ratio,

comparative example

A continuous casting graphite product of Hill Tianbao carbon manufacturing Limited company, Henan province, was used as a control example.

Test examples Performance test

The following properties were measured for the continuous cast graphite prepared in example 1 and the continuous cast graphite of the comparative example, and the methods for measuring the properties were as follows:

breaking strength: GB/T3074.1-2021; compressive strength: GB/T1431-; shore hardness: GB/T39535-2020; bulk density: GB/T245728-2009; resistivity: GB/T24255-2009; coefficient of thermal expansion: GB/T3074.4-2016; thermal conductivity: GB/T8722 and 2019, namely a method for measuring the thermal conductivity of carbon materials; particle size: GB/T21354-.

The results are shown in Table 1.

TABLE 1 measurement results of Properties of continuously cast graphite

	Example 1	Comparative example
			Flexural strength (MPa)	50	35
Compressive strength (MPa)	85	60
			Shore hardness	65	45
Bulk Density (g/cm) ³ )	1.85	1.75
			Resistivity (u Ω m)	12	15
Coefficient of thermal expansion 10 ^-6 /℃	9.5	9.8
			Thermal conductivity w/(mk)	110	108
Average particle size (um)	15-17	16-18
			Application scope	Continuous casting graphite	Continuous casting graphite

As can be seen from the test results of table 1: the copper pipe molding continuous casting graphite has good physical, mechanical and chemical properties, and the breaking strength is high and reaches 50MPa or even above; the compressive strength is good and reaches 85MPa or even above; the hardness is high, and the Shore hardness reaches 70; the resistivity is low and is lower than 12u omega m; low coefficient of thermal expansion, less than 9.5X 10 ^-6 /° c; the thermal conductivity is high and reaches 110 w/(mk). The continuous casting graphite material has high wear resistance, good sealing performance and good heat conduction in the using process.

The terminology used herein is for the purpose of description and illustration, and is not intended to be limiting. As the present invention may be embodied in several forms without departing from the spirit or essential characteristics thereof, it should also be understood that the above-described embodiments are not limited by any of the details of the foregoing description, but rather should be construed broadly within its spirit and scope as defined in the appended claims, and therefore all changes and modifications that fall within the meets and bounds of the claims, or equivalences of such meets and bounds are therefore intended to be embraced by the appended claims.

Claims

1. A preparation method of a continuous casting graphite material is characterized by comprising the following steps:

7) putting the first sintered blank into an impregnation tank for vacuumizing until the vacuum degree in the impregnation tank is lower than 5torr (preferably 3-5torr), adding molten medium-temperature asphalt into the impregnation tank, and then performing pressurization-impregnation treatment to obtain an impregnated blank;

2. The preparation method of claim 1, wherein the raw materials of the continuous casting graphite comprise, by weight:

。

3. the production method according to claim 1 or 2, wherein the first kneading treatment temperature in step 1) is 90 to 100 ℃; the second kneading treatment temperature is 160-180 ℃; the third kneading temperature was 160-.

4. The method according to claim 1 or 2, wherein the size of the mixed crushed material in the step 2) is not more than 40 mesh.

5. The production method according to claim 1 or 2, wherein the pressure of the press treatment in the step 4) is 2 to 6MPa, preferably 2 to 5 MPa; the pressing treatment time is 25-40 min.

6. The method according to claim 1 or 2, wherein the first sintering temperature in step 6) is 900-1000 ℃, preferably 900-950 ℃; the first sintering treatment time is 25 to 30 days, preferably 25 days.

7. The process according to claim 1 or 2, wherein the pressure-impregnation treatment in step 7) is carried out at a relative pressure of 2 to 3.5MP, preferably 2 to 3.0 MPa; the pressure-impregnation treatment time is 8 to 10 hours, preferably 9 hours.

8. The method according to claim 1 or 2, characterized in that the temperature of the second sintering treatment in step 8) is 900-1000 ℃, preferably 900-950 ℃; the second sintering time is 35 to 45 days, preferably 40 days.

9. The process according to claim 1 or 2, wherein the graphitization treatment in step 9) is carried out at a temperature of 2700-; the graphitization treatment time is 600-650h, preferably 600 h.

10. A continuously cast graphite material, characterized by being produced according to the method of any one of claims 1 to 9.