KR101685705B1 - Method for synthesis of silicon carbide whisker using seta of chaff - Google Patents

Abstract

The present invention relates to a method of synthesizing silicon carbide whiskers using rice hull bristles, and more particularly, to a method for synthesizing silicon carbide whiskers using a bristle bristle, which comprises mixing the bristles or the bristles with a carbon compound to prepare a synthesis raw material step; A first heat treatment step of heating the starting material for synthesis at a temperature of 200 ° C to 1000 ° C for 2 hours to 24 hours; An impurity removal step of removing the first impurities by heating the synthetic raw material after the first heat treatment step at a temperature of 1000 ° C to 1200 ° C for 30 minutes to 3 hours; A first synthesis step of heating the synthetic raw material having undergone the impurity removal step at a temperature of 1200 ° C to 1500 ° C for 5 minutes to 3 hours to generate nuclei of silicon carbide whiskers; And a second synthesis step of producing a silicon carbide whisker by growing the nucleus of the silicon carbide whisker by heating the synthetic raw material having passed through the first synthesis step at a temperature of 1550 to 2000 캜 for 5 minutes to 10 hours .
According to the present invention, the whiskers can be synthesized with the bristles themselves instead of the conventional rice husk, or the bristles and the carbon compounds can be synthesized under the optimum conditions, so that the production yield of the silicon carbide whiskers can be improved by three times or more as compared with the prior art, The economic efficiency is improved by the unit price, and the quality of the produced silicon carbide whisker is also excellent.

Description

FIELD OF THE INVENTION [0001] The present invention relates to a method of synthesizing a silicon carbide whisker using a bristle bristle,

The present invention relates to a method for synthesizing silicon carbide whiskers using bristle bristles, and more particularly, to a method for synthesizing whiskers with a bristle itself in place of a conventional rice husk, to develop an optimum mixing ratio between the bristles and the carbon compound, The present invention relates to a method for synthesizing silicon carbide whiskers using hank bristles capable of reducing the productivity and the manufacturing cost by synthesizing them under optimum conditions and improving the production yield and quality of the silicon carbide whiskers.

In recent years, silicon carbide (SiC) has been widely used for high-temperature structural materials and abrasive materials due to excellent properties such as heat resistance, corrosion resistance, oxidation resistance and abrasion resistance. In addition, since the characteristic of a wide bandgap (WBG) has been known recently, it has been used more actively as a material for semiconductors. In particular, the silicon carbide whiskers first discovered in the synthesis of silicon carbide from the thermal carbon reduction process are needle-like single crystals having a large aspect ratio and have a high strength close to the theoretical strength, , Metal-base, and ceramics-base composites to improve various properties such as strength, toughness, abrasion resistance, and thermal conductivity.

Conventional silicon carbide is most often produced by the Etching method, in which the reaction formula of SiO ₂ + 3C -> SiC + 2CO takes place in the Acheson furnace. In the chiseun within communicated electricity between both ends of the electrodes of the core (core) filled with graphite particles, and while the one SiO ₂ and coke blended raw material charge around cause the reaction raises the temperature the SiC is produced in the core outer wall. Silicon carbide produced by the Etching method has a-silicon carbide synthesized at a high temperature of 2000 DEG C or higher and beta-silicon carbide synthesized at 2000 DEG C or lower. In the synthesized silicon carbide, powder and whisker exist at the same time. If necessary, powder and whisker are separated and used.

Mechanisms in which silicon carbide whiskers are synthesized are divided into a vapor-solid growth mechanism, a two-stage growth mechanism, and a vapor-liquid-solid growth mechanism . In the gas phase-solid phase apparatus, whiskers grow due to vapor deposition of SiO and CO directly on the growth portion of the whiskers, and the whiskers thus grown are known to have poor properties due to lamination defects.

In addition, the two-stage growth is a mechanism for allowing metal droplets to grow rapidly in one direction while forming small droplets on the growth surface in the presence of metallic impurities in the raw material. In the vapor-liquid-solid-phase apparatus, whiskers grow as the Si and C components dissolve in the liquid droplets formed from the metal impurity catalyst and re-precipitation occurs at the growth surface. The silicon carbide whiskers thus grown have almost no lamination defect, Is known to have excellent properties.

Recently, a technique of synthesizing silicon carbide by heating waste silicon sludge containing a abrasive and cutting oil and a mixture of carbon has been developed. However, most of the silicon carbide synthesized by this method is a silicon carbide powder having low commerciality, Since it requires separate processing to make it into a whisker, it is not economical.

Conventionally, silicon carbide whiskers were synthesized by using rice husk as a raw material. This is because the content of silica is low and the production yield is as low as about 5% as compared with the input rice husk, and the amount of rice husk is limited The problem is that the raw material costs are also significant.

However, in addition to rice hulls, the amount of wastes to be discarded as byproducts during the rice milling process is considerable, and these are waste materials that can not be recycled.

Further, there is a problem that the quality of the silicon carbide whisker produced by using the rice hull can not be further improved by merely improving the synthesis process.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems and it is an object of the present invention to provide a method of manufacturing a silicon carbide whisker from a bristle wasted as waste in a milling process, And a method for synthesizing silicon carbide whiskers using the bristle bristles having high economic efficiency.

Further, a method of synthesizing silicon carbide whiskers using a bristle bristle having a high silica content of bristles used as raw materials and synthesizing them under optimal conditions with a carbon compound to improve the production yield of silicon carbide whiskers by three times or more .

It is another object of the present invention to provide a method for synthesizing silicon carbide whiskers using a bristle bristle having improved purity and quality of silicon carbide whiskers compared with conventional ones through optimal synthesis conditions and purification processes.

According to another aspect of the present invention, there is provided a method of synthesizing a silicon carbide whisker using a bristle bristle, the method comprising: mixing the bristle or the bristle with a carbon compound A mixing step of producing a starting material for synthesis; A first heat treatment step of heating the starting material for synthesis at a temperature of 200 ° C to 1000 ° C for 2 hours to 24 hours; An impurity removal step of removing the first impurities by heating the synthetic raw material after the first heat treatment step at a temperature of 1000 ° C to 1200 ° C for 30 minutes to 3 hours; A first synthesis step of heating the synthetic raw material having undergone the impurity removal step at a temperature of 1200 ° C to 1500 ° C for 5 minutes to 3 hours to generate nuclei of silicon carbide whiskers; And a second synthesis step of producing a silicon carbide whisker by growing the nucleus of the silicon carbide whisker by heating the synthetic raw material having passed through the first synthesis step at a temperature of 1550 to 2000 캜 for 5 minutes to 10 hours .

A classification step of classifying the silicon carbide whisker; And a second heat treatment step of heating the silicon carbide whiskers having passed through the classification step at a temperature of 200 ° C to 1000 ° C for 1 hour to 6 hours under a pressure of 600 mmHg to 850 mmHg.

In the mixing step, the carbon compound may include 100 to 500 parts by weight based on 100 parts by weight of the bristles, and the carbon compound may be a carbon compound.

Wherein the first heat treatment step is performed under an inert gas atmosphere or under a pressure of 0.00001 mmHg to 0.001 mmHg. In the impurity removing step, the first impurities are removed from the bristles and the carbon compound .

The classifying step may include chopping the silicon carbide whisker; The silicon carbide whiskers that have undergone the chopping step are mixed with water to prepare a mixed solution. After the mixed solution is stirred or exposed to ultrasonic waves, an organic solvent is added to the mixed solution, and the mixed solution is stirred or re- A first classification step of separating the second impurities contained in the whiskers; A second classifying step of adding an organic solvent to the mixed solution and then collecting the separated second impurities in an organic solvent by stirring or ultrasonic waves; Filtering the mixed solution through a filter having a gap of 0.5 m to 20 m to separate the silicon carbide whisker and the water in the mixed solution; And drying the silicon carbide whiskers having passed through the filtration step at a temperature of 20 to 200 DEG C for 1 to 10 hours.

Further, in the first classifying step, the secondary impurity is at least one of a carbon compound or particulate matter of silicon carbide.

According to the method for synthesizing silicon carbide whiskers using the rice husk bristles of the present invention, by developing a method for producing silicon carbide whiskers from raw bristles, which are discarded as wastes during the milling process, unlike the prior art, Of silicon carbide whiskers are produced, which is advantageous in terms of economy.

Also, there is an advantage that the silica content of the bristles used as the raw material is high, and the production yield of the silicon carbide whisker is improved three times or more as compared with the conventional one by synthesizing the silica with the carbon compound under the optimum conditions.

In addition, there is an advantage that the purity and quality of the silicon carbide whiskers are greatly improved compared with the conventional ones through optimum synthesis conditions and purification processes.

Brief Description of the Drawings Fig. 1 is a flow chart sequentially showing an embodiment of a method of synthesizing silicon carbide whiskers using bristle bristles according to the present invention
Fig. 2 is a photograph showing the rice husk (rice bran)
Fig. 3 shows photographs of rice husks (rice bran) photographed before the drying process or the first boiling process
Fig. 4 is a photograph of the rice husk (rice bran) taken after the drying process or the first boiling process
FIG. 5 is a photograph of the bristles used in the present invention photographed with an optical microscope
6 is a photograph (a: 1,000 times magnification, b: 5000 times magnification, c: 5000 times magnification) photograph of a commercially available grade A silicon carbide whisker taken by an electron microscope,
7 is a photograph (a: 1000 times magnification, b: 5000 times magnification, c: 5000 times magnification) photographing the silicon carbide whisker produced by the present invention,

BEST MODE FOR CARRYING OUT THE INVENTION One preferred embodiment of the present invention will now be described in detail with reference to the accompanying drawings by way of a method for synthesizing silicon carbide whiskers using bristle bristles according to the present invention. The present invention may be better understood by the following examples, which are for the purpose of illustrating the present invention and are not intended to limit the scope of protection defined by the appended claims.

As shown in FIG. 1, the method for synthesizing silicon carbide whiskers using the rice husk bristles according to the present invention comprises a mixing step S10, a first heat treatment step S20, an impurity removing step S30, a nucleation step S40 , A nucleus growth step (S50), a classification step (S60), and a second heat treatment step (S70).

First, the mixing step (S10) is a step of mixing the bristles or the bristles with a carbon compound to produce a starting material for synthesis. This is for the purpose of producing a starting material for synthesis of a silicon carbide whisker by mixing it with a carbon compound to form a raw material for the bristles.

Here, the bristles are present on the surface of rice husks (rice bran), especially the region where the content of silica is particularly high. In the drying process of removing the moisture of the rice ball at the beginning of the milling process of the rice paddy, the bristles collide with each other and the bristles on the surface of the rice hull are separated and the separated bristles are collected into a collecting duct collecting dust from the dryer in the form of dust. In addition, the rice grain is rubbed in the first marbling process, and the remaining bristles are collected in the second order.

These bristles are completely waste products which can not be sold in houses or the like unlike rice hulls, and they are advantageously used as raw materials in the present invention, thereby remarkably lowering the manufacturing cost.

The carbon black may be any material including carbon, but it is most preferable to use carbon black as a result of several experiments. The carbon black is a black fine carbon powder composed of carbon , Whisker synthesis is used as needed, and any form is acceptable.

In the mixing step (S10), the carbon compound preferably contains 100 to 500 parts by weight, more preferably 150 to 450 parts by weight, and most preferably 300 parts by weight, based on 100 parts by weight of the bristles to be. When the amount of the carbon compound is less than 100 parts by weight, the synthesis reaction with the bristles does not occur well and the production yield of the silicon carbide whisker is significantly lowered. When the amount exceeds 500 parts by weight, , There is a problem that the synthesis reaction does not occur completely and the quality of the silicon carbide whisker is deteriorated.

Here, the mixing method may be mixed in any manner, but it is most preferable to improve the synthesis efficiency by using ball milling or blender as a result of several experiments.

Next, the first heat treatment step (S20) is a step of heating the starting materials for synthesis at a temperature of 200 ° C to 1000 ° C for 2 hours to 24 hours. This is to remove external impurities such as moisture, lignin and hemicellulose present in the bristles, and to increase the efficiency of the synthesis reaction thereafter.

The temperature of the first heat treatment step (S20) is preferably 200 ° C to 1000 ° C, more preferably 250 ° C to 750 ° C, and most preferably 600 ° C. If the temperature is less than 200 ° C, the external impurities are not removed well and the contribution to the improvement of the synthetic reactivity is also insignificant. If the temperature exceeds 1000 ° C, the proportion of carbon present in the bristles changes, .

The heating time is preferably 2 hours to 24 hours, more preferably 7 hours to 19 hours, and most preferably 14 hours. In the case of less than 2 hours, the external impurities are not removed well, and the contribution to the improvement of the synthetic reactivity is also insignificant. If it exceeds 24 hours, there is a problem in productivity and efficiency.

The first heat treatment step (S20) is preferably carried out under an inert gas atmosphere or under a pressure of 0.00001 mmHg to 0.001 mmHg. It is possible to effectively decompose impurities, water, lignin, and cellulose which are not necessary for whisker synthesis, and which is capable of effectively decomposing under the atmospheric pressure of 0.00001 mmHg to 0.001 mmHg If it proceeds, it is advantageous that the impurities can be effectively decomposed because it is close to a vacuum state.

However, when the air pressure is less than 0.00001 mmHg, the cost is low because the cost is low to lower the air pressure, and when the air pressure is more than 0.001 mmHg, the components in the bristles may react.

The impurity removal step (S30) is a step of removing the first impurities by heating the synthetic raw material after the first heat treatment step (S20) at a temperature of 1000 to 1200 占 폚 for 30 minutes to 3 hours. This is a process for effectively removing impurities in bristles and carbon compounds.

Here, the primary impurity means all of the substances contained in the synthetic raw material except for the bristles and the carbon compound. It is mainly present inside bristles and carbon compounds.

In the impurity removing step (S30), most of the impurities remaining in the bristles and the carbon compound can be removed by performing the heat treatment at a relatively high temperature, as opposed to simply removing the impurities of the bristles and the carbon compound raw material in the first heat treatment step (S20) .

Therefore, the temperature is preferably 1000 deg. C to 1200 deg. C, more preferably 1020 deg. C to 1080 deg. C, and most preferably 1150 deg. If the temperature is lower than 1000 ° C, the temperature is lowered to lower the removal rate of the primary impurities. If the temperature is higher than 1200 ° C, nuclei of the silicon carbide whisker may be partially formed, thereby lowering the synthesis efficiency of the synthesis step .

The heating time is preferably 30 minutes to 3 hours, more preferably 1 hour to 2 hours, and most preferably 1 hour and 30 minutes. In the case of less than 30 minutes, the primary impurity removal rate is lowered. If it exceeds 3 hours, not only the economical efficiency is lowered but also the synthesis efficiency of synthesis step is lowered.

The first synthesis step (S40) is a step of generating nuclei of the silicon carbide whisker by heating the synthetic raw material after the impurity removal step (S30) at a temperature of 1200 to 1500 DEG C for 5 minutes to 3 hours. This is the initial stage of silicon carbide whisker generation, and is a process for producing the nuclei of silicon carbide whiskers present in bristles through heat treatment.

Here, the temperature is preferably 1200 ° C to 1500 ° C, more preferably 1220 ° C to 1480 ° C, and most preferably 1450 ° C. When the temperature is lower than 1200 ° C., the temperature of the silicon carbide whisker is low, and the generation rate of the silicon carbide whisker is low. In addition, when the temperature is higher than 1500 ° C., the nucleation rate is low. There is a problem in that the quality of the silicon carbide whisker is remarkably deteriorated.

The heating time is preferably 5 minutes to 3 hours, more preferably 30 minutes to 150 minutes, and most preferably 100 minutes. When it is less than 5 minutes, there is a problem that the nucleation rate of silicon carbide whisker is low, and when it exceeds 3 hours, not only the economical efficiency is lowered but also the quality of the produced silicon carbide whisker is remarkably deteriorated.

In the second synthesis step (S50), the synthesis starting material after the first synthesis step is heated at a temperature of 1550 DEG C to 2000 DEG C for 5 minutes to 10 hours to grow whiskers at the nucleus of the silicon carbide whisker to synthesize silicon carbide whiskers . This is a step in which the synthesis reaction takes place in earnest and is a process for manufacturing high quality silicon carbide whiskers by promoting the growth of whiskers from the nuclei of silicon carbide whiskers through heat treatment at a high temperature.

Here, the temperature is preferably 1550 ° C to 2000 ° C, more preferably 1600 ° C to 1950 ° C, and most preferably 1650 ° C. When the temperature is lower than 1550 DEG C, the temperature of the silicon carbide whisker is low, so that the growth rate of the core of the silicon carbide whisker is slow and the production yield of the silicon carbide whisker is low. When the temperature exceeds 2000 DEG C, There is a problem in that the quality of the silicon carbide whisker produced is remarkably deteriorated.

The heating time is preferably 5 minutes to 10 hours, more preferably 60 minutes to 90 minutes, and most preferably 3 hours. If it is less than 5 minutes, the production yield of silicon carbide whisker is low. If it exceeds 10 hours, not only the economical efficiency is lowered but also the quality of the produced silicon carbide whisker is deteriorated.

It is preferable that the mixing step (S10) to the second synthesis step (S50) are performed in order, and it is most preferable to leave an interval of 10 minutes to 1 hour between each step, but it may be performed continuously. In addition, the mixing step (S10) to the second combining step (S50) is an essential step in the synthesis of silicon carbide whiskers. The following steps may not be carried out as an optional step but are preferably carried out in order to produce refined silicon carbide whiskers of higher quality.

Next, the classification step S60 is a step of classifying the silicon carbide whiskers generated in the second synthesis step S50. This is because the impurities contained in the silicon carbide whiskers produced through the mixing step (S10) to the second synthesis step (S50) are removed without affecting the composition and quality of the silicon carbide whiskers, whereby the purity of the silicon carbide whiskers It is a process to improve the quality.

The classifying step S60 includes a chopping step S61, a first classifying step S62, a second classifying step S63, a filtering step S64, and a drying step S65. This is to improve the purity of the silicon carbide whiskers significantly in comparison with the conventional ones by various classification processes.

The chopping step S61 is a step of crushing the silicon carbide whiskers synthesized in the second synthesis step S50. This is to separate silicon carbide whiskers that are entangled in the form of a mat.

The pulverizing method may be any method, but it is preferable to use a pulverizer, a knife, or a chopper.

The first classifying step S62 is a step of mixing the silicon carbide whisker after the chopping step S61 with water to prepare a mixed solution and stirring or exposing the mixed solution to ultrasonic waves, Is a step in which an organic solvent is added to the mixed solution, and then the mixture is stirred or exposed to ultrasonic waves to collect the separated second impurities in an organic solvent.

This is because the silicon carbide whiskers that have been subjected to the chopping step S61 include secondary impurities such as carbon compounds and silicon carbide particulate matter containing carbon. Therefore, the characteristics of the silicon carbide whiskers having hydrophilicity and the characteristics of the carbon compounds and hydrophobic This is to effectively separate impurities from silicon carbide whiskers by using the characteristics of impurities such as materials.

In the first classifying step S62, the silicon carbide whiskers after the chopping step S61 are mixed with water, and the mixing may be carried out in any manner, but it is preferable to expose or shake the mixture to ultrasonic waves. This removes impurities such as carbon compounds attached to the silicon carbide whiskers.

After the first classification step (S62), the second classification step (S63) is performed by adding an organic solvent to the mixed solution and re-stirring or exposing the mixture to ultrasonic waves to remove secondary impurities contained in the silicon carbide whisker. This is based on the principle that the organic solvent collects the carbon compound and the grain, floats on the water, and conversely, the silicon carbide whisker precipitates.

Here, any organic solvent may be used, but it is most preferable to use a petroleum-based product to improve the classification efficiency.

The first classification step (S62) and the second classification step (S63) are preferably repeated two to eight times, more preferably four to six times. When the number of times is less than 2, the classification effect is low. When the number of times is more than 8, economical efficiency is low. Here, it is preferable that the repetition is performed in the order of the first classification step S62, the second classification step S63, the first classification step S62, and the second classification step S63.

Further, the secondary impurity means at least one of the carbon compound and the silicon carbide particulate matter containing carbon.

The filtration step (S64) is a step of filtering the mixed solution through a filter having a gap of 0.5 mu m to 20 mu m to separate the silicon carbide whisker and the water in the mixed solution. This is the process of removing water used for classification. The silicon carbide whiskers are filtered through the filter, and the water is passed through the filter.

Here, it is effective that the size of the pores of the filter is 0.5 탆 to 20 탆, more preferably 7 탆 to 15 탆, and most preferably 10 탆. When the size of the pores is less than 0.5 탆, it is difficult to pass through the pores due to the surface tension of the water used for classification. When the pore size exceeds 20 탆, there is a problem that not only water but also silicon carbide whiskers pass through the pores.

The drying step (S65) is a step of drying the silicon carbide whisker through the filtration step (S64) at 20 DEG C to 200 DEG C for 1 hour to 10 hours. This is a process for completely removing water that has not been filtered in the filtration step S64.

If the drying temperature is lower than 20 ° C, the drying time is long and the drying efficiency is low. If the drying temperature is higher than 200 ° C, the economical efficiency is lowered. If the drying time is less than 1 hour, drying can not be completed. If the drying time is more than 10 hours, economical efficiency is low.

Finally, the second heat treatment step (S70) is a step of heating the silicon carbide whiskers subjected to the classification step at a temperature of 200 to 1000 占 폚 for 1 to 6 hours under a pressure of 600 mmHg to 850 mmHg. This is carried out in order to remove residual carbon components which may remain after the classification treatment and to improve the purity and quality of the silicon carbide whiskers.

In the second heat treatment step (S70), the atmospheric pressure is preferably 600 mmHg to 850 mmHg, more preferably 700 mmHg to 800 mmHg. When it is less than 600 mmHg or exceeds 850 mmHg, the silicon carbide whisker may be damaged during the heat treatment, and the heat treatment efficiency is inferior.

Here, the temperature is preferably 200 ° C to 1000 ° C, more preferably 350 ° C to 750 ° C, and most preferably 700 ° C. When the temperature is less than 200 ° C, there is a problem that the heat treatment efficiency is low. When the temperature exceeds 700 ° C, there is a problem of quality deterioration due to oxidation of whiskers.

The heating time is preferably 1 hour to 6 hours, more preferably 1 hour and 30 minutes to 5 hours and 30 minutes, and most preferably 4 hours. If it is less than 1 hour or exceeds 6 hours, there is a problem of heat treatment efficiency and poor quality of whiskers.

Hereinafter, the superiority of the present invention will be demonstrated through Examples and Comparative Examples of silicon carbide whiskers produced by the method of synthesizing silicon carbide whiskers using the rice hick bristles of the present invention.

Production yields of the silicon carbide whiskers prepared in Examples 1 and 2 and the conventional silicon carbide whiskers produced by the present invention were measured, and the results are shown in Table 1 below.

Initial charge After the first heat treatment 2 After the synthesis step After classification stage After the second heat treatment Example 1 100 58.3 20.4 18.1 15.4 Example 2 100 50.87 17 16.1 14.6 Comparative Example 100 49.2 20.3 6.4 5.7

                                                             (unit: %)

As shown in Table 1, Examples 1 and 2 produced by the present invention show a production yield three times higher than that of the comparative example used in the prior art. In other words, it can be seen that the production of silicon carbide whiskers by the present invention is far superior to that of the prior art.

6 is a photograph (a: 1000 times magnification, b: 5000 times magnification, c: 5000 times magnification) photograph of a commercially available grade A silicon carbide whisker taken by an electron microscope, The silicon carbide whiskers manufactured by the present invention are currently sold (a: 1000 times magnification, b: 5000 times magnification, c: 5000 times magnification) taken by an electron microscope It can be seen that the purity is higher and the quality is better than the A-grade silicon carbide whisker.

The present invention has been described in detail with reference to the preferred embodiments thereof. However, the scope of the present invention is not limited to the above embodiments, but may be embodied in various forms of embodiments within the scope of the appended claims. 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 present invention as defined by the appended claims.

Claims (8)

In a method for synthesizing silicon carbide whiskers using bristle bristles,
Mixing the bristles or the bristles with a carbon compound to produce a starting material for synthesis;
A first heat treatment step of heating the starting material for synthesis at a temperature of 200 ° C to 1000 ° C for 2 hours to 24 hours;
The synthetic raw material having been subjected to the first heat treatment step is heated at a temperature of 1000 ° C to 1200 ° C for 30 minutes to 3 hours to remove impurities from the bristles and the carbon compound contained in the synthetic raw materials, step;
A first synthesis step of heating the synthetic raw material having undergone the impurity removal step at a temperature of 1200 ° C to 1500 ° C for 5 minutes to 3 hours to generate nuclei of silicon carbide whiskers;
And a second synthesis step of producing a silicon carbide whisker by growing the nucleus of the silicon carbide whisker by heating the synthetic raw material having passed through the first synthesis step at a temperature of 1550 to 2000 캜 for 5 minutes to 10 hours Method of synthesizing silicon carbide whisker using bristle bristles
The method according to claim 1,
A classification step of classifying the silicon carbide whiskers;
And a second heat treatment step of heating the silicon carbide whiskers having passed through the classification step at a temperature of 200 ° C. to 1000 ° C. for 1 hour to 6 hours under a pressure of 600 mmHg to 850 mmHg. Synthesis method of silicon whisker
3. The method according to claim 1 or 2,
In the mixing step, the carbon compound includes 100 to 500 parts by weight based on 100 parts by weight of the bristles, and a method of synthesizing the silicon carbide whisker using the bristle bristles
3. The method according to claim 1 or 2,
In the above mixing step, the carbon compound is carbon black. A method for synthesizing silicon carbide whisker using a bristle bristle
3. The method according to claim 1 or 2,
Wherein the first heat treatment step is carried out in an inert gas atmosphere or under a pressure of 0.00001 mmHg to 0.001 mmHg. delete 3. The method of claim 2,
In the classifying step,
A chopping step of crushing the silicon carbide whisker;
The silicon carbide whiskers that have undergone the chopping step are mixed with water to prepare a mixed solution. After the mixed solution is stirred or exposed to ultrasonic waves, an organic solvent is added to the mixed solution, and the mixed solution is stirred or re- A first classification step of separating the second impurities contained in the whiskers;
A second classifying step of adding an organic solvent to the mixed solution and then collecting the separated second impurities in an organic solvent by stirring or ultrasonic waves;
Filtering the mixed solution through a filter having a gap of 0.5 m to 20 m to separate the silicon carbide whisker and the water in the mixed solution;
And a drying step of drying the silicon carbide whiskers having passed through the filtration step at 20 ° C to 200 ° C for 1 hour to 10 hours to obtain a silicon carbide whisker.
8. The method of claim 7,
In the first classifying step, the second impurity is at least one of a carbon compound or particulate matter of silicon carbide. The method of synthesizing silicon carbide whisker using a bristle bristle

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