CN114988900B - Method for preparing whisker toughened ceramic matrix composite by dynamic pressure flash firing - Google Patents
Method for preparing whisker toughened ceramic matrix composite by dynamic pressure flash firing Download PDFInfo
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- 239000011153 ceramic matrix composite Substances 0.000 title claims abstract description 34
- 238000000034 method Methods 0.000 title claims abstract description 24
- 238000010304 firing Methods 0.000 title claims abstract description 20
- 239000000919 ceramic Substances 0.000 claims abstract description 101
- 230000005684 electric field Effects 0.000 claims abstract description 30
- 239000000843 powder Substances 0.000 claims abstract description 23
- 239000011812 mixed powder Substances 0.000 claims abstract description 22
- 238000005245 sintering Methods 0.000 claims abstract description 12
- 238000002360 preparation method Methods 0.000 claims abstract description 10
- 238000001816 cooling Methods 0.000 claims abstract description 9
- 238000003825 pressing Methods 0.000 claims abstract description 9
- 238000005242 forging Methods 0.000 claims abstract description 4
- 230000010355 oscillation Effects 0.000 claims description 26
- 239000002002 slurry Substances 0.000 claims description 16
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 12
- 239000008367 deionised water Substances 0.000 claims description 10
- 229910021641 deionized water Inorganic materials 0.000 claims description 10
- 238000000227 grinding Methods 0.000 claims description 8
- 238000002390 rotary evaporation Methods 0.000 claims description 8
- 238000007873 sieving Methods 0.000 claims description 8
- 238000010438 heat treatment Methods 0.000 claims description 7
- 239000002131 composite material Substances 0.000 claims description 6
- 238000004321 preservation Methods 0.000 claims description 5
- 229910018072 Al 2 O 3 Inorganic materials 0.000 claims description 3
- 238000002156 mixing Methods 0.000 claims description 2
- 239000002245 particle Substances 0.000 claims description 2
- 238000001132 ultrasonic dispersion Methods 0.000 claims description 2
- 238000004519 manufacturing process Methods 0.000 claims 2
- 239000000463 material Substances 0.000 abstract description 22
- 230000008569 process Effects 0.000 abstract description 12
- 238000000280 densification Methods 0.000 abstract description 10
- 230000007547 defect Effects 0.000 abstract description 7
- 229910010293 ceramic material Inorganic materials 0.000 abstract description 2
- 230000008878 coupling Effects 0.000 abstract description 2
- 230000001808 coupling effect Effects 0.000 abstract description 2
- 238000010168 coupling process Methods 0.000 abstract description 2
- 238000005859 coupling reaction Methods 0.000 abstract description 2
- MCMNRKCIXSYSNV-UHFFFAOYSA-N Zirconium dioxide Chemical compound O=[Zr]=O MCMNRKCIXSYSNV-UHFFFAOYSA-N 0.000 description 20
- 238000001514 detection method Methods 0.000 description 11
- 239000011148 porous material Substances 0.000 description 5
- 238000003756 stirring Methods 0.000 description 4
- 238000009792 diffusion process Methods 0.000 description 3
- 230000005457 Black-body radiation Effects 0.000 description 2
- 239000011159 matrix material Substances 0.000 description 2
- 230000001737 promoting effect Effects 0.000 description 2
- 230000005540 biological transmission Effects 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 210000000988 bone and bone Anatomy 0.000 description 1
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- 239000013078 crystal Substances 0.000 description 1
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- 230000006872 improvement Effects 0.000 description 1
- 230000000977 initiatory effect Effects 0.000 description 1
- 239000007769 metal material Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 230000006641 stabilisation Effects 0.000 description 1
- 238000011105 stabilization Methods 0.000 description 1
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- C04B35/71—Ceramic products containing macroscopic reinforcing agents
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- C04B35/48—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics based on zirconium or hafnium oxides, zirconates, zircon or hafnates
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Abstract
The invention belongs to the technical field of ceramic material preparation, and particularly relates to a method for preparing a whisker toughened ceramic matrix composite material by dynamic pressure flash firing. The method comprises the steps of preparing ceramic mixed powder from whisker and ceramic powder, pressing the ceramic mixed powder into a ceramic blank, applying oscillating pressure to the upper end and the lower end of the ceramic blank while carrying out flash firing on the ceramic blank, realizing dynamic force-assisted flash firing, forging and sintering, and finally cooling to obtain the whisker toughened ceramic matrix composite. In the sintering process, the invention adopts the coupling of a thermal field, a dynamic force field and an electric field, realizes the reduction of sintering temperature under the coupling effect, accelerates the densification rate of ceramic, and finally prepares the whisker toughened ceramic matrix composite material with small grain size, less internal defects, stable whisker structure and high compactness.
Description
Technical Field
The invention belongs to the technical field of ceramic material preparation, and particularly relates to a method for preparing a whisker toughened ceramic matrix composite material by dynamic pressure flash firing.
Background
Whisker toughened ceramic matrix composite is an effective measure for improving the brittleness of ceramics, and is always a research hot spot in the direction of high-performance structural ceramics at home and abroad. However, since the rigid ceramic whisker hardly contracts during sintering, when the ceramic matrix contracts, a circumferential tensile stress and a radial tensile stress are generated around the ceramic whisker, which hinders the ceramic matrix from further contracting, and the densification of the composite material is difficult. Therefore, development of a new method for solving the problem that whisker toughened composite materials are difficult to sinter is urgently needed.
Disclosure of Invention
In view of the above, the invention aims to provide a method for preparing a whisker toughened ceramic matrix composite material by dynamic pressure flash firing, which solves the problems that the whisker toughened composite material is difficult to sinter and the composite material is difficult to densify.
The technical scheme adopted by the invention is as follows:
a method for preparing whisker toughened ceramic matrix composite by dynamic pressure flash firing comprises the following steps:
1) Uniformly mixing the whisker and ceramic powder to prepare ceramic mixed powder;
2) Pressing the ceramic mixed powder into a ceramic blank;
3) Placing the ceramic blank in a furnace body, heating the furnace body to a certain temperature, applying an electric field to the ceramic blank for flash firing, applying oscillating pressure to the upper end and the lower end of the ceramic blank while carrying out flash firing, and carrying out dynamic pressure-assisted flash firing, forging and sintering;
4) And after the heat preservation is carried out for a certain time, stopping the oscillation pressure and the electric field, and cooling to obtain the whisker toughened ceramic matrix composite.
The furnace body in the step 3) is heated to 500-1200 ℃; the electric field strength is 50-300V/cm, and the current density is 60-200 mA/mm 2 。
The median value of the oscillating pressure in the step 3) is calculated to be 10-150 MPa according to the area, the amplitude value is 5-50 MPa, the frequency value is 0.5-20 Hz, and the power value of the product of the amplitude value and the frequency is not more than 200.
The application of the oscillating pressure in step 3) may be performed before or after the initiation of the flash, but not after the flash stabilization phase.
The specific steps of the step 1) are as follows: the whisker and the ceramic powder are dispersed in water by ultrasonic to obtain ceramic slurry, and the ceramic slurry is subjected to rotary evaporation, grinding and sieving to obtain ceramic mixed powder, wherein the particle size of the ceramic mixed powder is 150 microns.
The whisker comprises: the proportion of the ceramic powder is 5-30%: 70-95% of deionized water, wherein the amount of deionized water is larger than the total amount of whisker and ceramic powder; the ultrasonic dispersion time is 6-48 h.
The whisker is SiC whisker or Al 2 O 3 Whisker, zrO 2 One of the whiskers; the ceramic powder is ZrO 2 Powder, al 2 O 3 One of the powders.
The heat preservation time in the step 4) is 5-30 min.
In the step 2), when the ceramic body is pressed, the pressed ceramic body can be in various shapes, such as dog bone shape, cylindrical shape, strip shape and the like, and the shape can be selected according to requirements.
Step 3) after an electric field is applied to the ceramic blank, the current of the blank slowly rises to a set value, then the voltage is converted into current control by voltage control, the voltage rapidly drops, a flash stable stage is entered, the state is completely flash-burned, and the heat is preserved under the preset current density.
The whisker toughened ceramic matrix composite material prepared by the method of the invention. The density range of the composite material is 96% -99.8%, and the hardness is 17.5-23.5GPa.
When an electric field and oscillation pressure are applied to the ceramic blank, the electric field can be simultaneously applied to the upper and lower pressure heads at the upper and lower ends of the ceramic blank, and the electric field is connected to the upper and lower pressure heads in two stages; the oscillating pressure can be applied to the upper end and the lower end of the ceramic body through the up-down pressure, and the electric field can be applied to other directions of the ceramic body, such as the left-right direction, and the specific electric field direction can be adjusted according to the shape of the ceramic body without fixing limitation.
In the present invention, it is well known that high strength structural ceramics are relatively brittle and have limited plastic deformability, requiring relatively high temperatures to effect deformation. The invention selects flash firing during preparation for about 3-30min, and can realize large-degree plastic deformation of the whisker toughened ceramic matrix composite material at a lower temperature, thereby realizing low-temperature rapid sintering, rapid material transmission and low-temperature superplastic deformation of the material. The problem of difficult sintering is overcome by simple flash firing, but the problem of difficult densification of the material is still not overcome.
The invention applies pressure while the flash burning is carried out, the pressure is not constant pressure but oscillation pressure, and the progress is not smooth while the oscillation pressure is applied, because the result of the flash burning directly influences whether the oscillation pressure can be applied or not. When the defects generated in the material by the flash are too small, rapid deformation and densification cannot be achieved even if an oscillating pressure is applied. When the flash burns to cause too many defects in the material, the defects are aggregated to cause formation of microscopic pores, and at this time, the pores cannot be removed even if an oscillation pressure is applied, thereby greatly reducing the performance of the material.
In the sintering process, the coupling of a thermal field, a dynamic force field and an electric field is adopted, the sintering temperature is reduced under the coupling effect, the densification rate is accelerated, and finally the ceramic matrix composite material with small grain size, few internal defects, stable whisker structure and high compactness is prepared.
Drawings
FIG. 1 is a scan (500 times) of the whisker-toughened ceramic matrix composite material prepared in example 1;
FIG. 2 is a scan (10000 times) of the whisker-toughened ceramic matrix composite material prepared in example 1;
FIG. 3 is a scan (500 times) of the ceramic matrix composite produced in example 5;
FIG. 4 is a scan (15000 times) of the ceramic matrix composite produced in example 5;
FIG. 5 is a scan of the ceramic matrix composite produced in example 6.
Detailed Description
The following examples are given to illustrate the invention in detail, but are not intended to limit the scope of the invention in any way.
Example 1:
the preparation method of the whisker toughened ceramic matrix composite comprises the following steps:
(1) Stirring the Al by ultrasonic for 10h 2 O 3 Fully dispersing 2g of whisker and 28g of zirconia powder in 100g of deionized water to obtain ceramic slurry with uniformly distributed whisker, and sequentially carrying out rotary evaporation, grinding and sieving on the ceramic slurry to obtain ceramic mixed powder of 150 microns;
(2) 4g of the ceramic mixed powder obtained in the step (1) is pressed, and after the pressing forming, a dog-bone-shaped ceramic blank A is obtained;
(3) Placing the ceramic blank A obtained in the step (2) between an upper pressure head and a lower pressure head, heating to a preset temperature of 800 ℃, then applying a preset electric field intensity on the upper pressure head and the lower pressure head of the ceramic blank, and starting to perform flash burning until the material is completely flash burned; wherein the electric field strength is 100V/cm, and the current density is 100 mA/mm 2 。
(4) After the ceramic body A is flash-burned and stabilized, an oscillation pressure with a median value of 30 MPa, an amplitude value of 5MPa and a frequency of 1Hz is applied by controlling an upper pressure head and a lower pressure head, the temperature is kept for 10 min, the oscillation force and flash-burning are stopped, and the whisker toughened zirconia ceramic matrix composite is obtained after cooling.
Through detection, the density of the final sample reaches 99.1 percent, and the hardness reaches 17.5GPa.
Example 2:
the preparation method of the whisker toughened ceramic matrix composite comprises the following steps:
(1) 2g of SiC whisker and Al are stirred for 10h by ultrasonic 2 O 3 10g of powder is fully dispersed in 50g of deionized water to obtain ceramic slurry with uniformly distributed whiskers, and then the ceramic slurry is subjected to rotary evaporation, grinding and sieving in sequence to obtain ceramic mixed powder of 150 microns;
(2) 3g of the ceramic mixed powder obtained in the step (1) is pressed, and after the pressing forming, a dog-bone-shaped ceramic blank A is obtained;
(3) The ceramic blank obtained in the step (2) is processedThe body A is arranged between an upper pressure head and a lower pressure head, the temperature is raised to a preset temperature of 1000 ℃, then a preset electric field intensity is applied to the upper pressure head and the lower pressure head of the ceramic blank, and the material starts to flash until the material is completely flash-burned; wherein the electric field strength is 200V/cm, and the current density is 8mA/mm 2 。
(4) When the ceramic body A starts to flash, the upper pressure head and the lower pressure head are controlled to apply oscillation pressure with the median value of 50MPa, the amplitude value of 10MPa and the frequency of 2Hz, the temperature is kept for 1.5min, the oscillation force and the flash are stopped, and the whisker toughened zirconia ceramic matrix composite is obtained after cooling.
Through detection, the density of the final sample reaches 99.3%, and the hardness reaches 23.5GPa.
Example 3:
the preparation method of the whisker toughened ceramic matrix composite comprises the following steps:
(1) 2g of SiC whisker and ZrO are stirred for 10h by ultrasonic wave 2 Fully dispersing 18g of powder in 100g of deionized water to obtain ceramic slurry with uniformly distributed whiskers, and sequentially carrying out rotary evaporation, grinding and sieving on the ceramic slurry to obtain ceramic mixed powder of 150 microns;
(2) 4g of the ceramic mixed powder obtained in the step (1) is pressed, and after the pressing forming, a dog-bone-shaped ceramic blank A is obtained;
(3) Placing the ceramic blank A obtained in the step (2) between an upper pressure head and a lower pressure head, heating to a preset temperature of 1000 ℃, then applying a preset electric field intensity on the upper pressure head and the lower pressure head of the ceramic blank, and starting to perform flash burning until the material is completely flash burned; wherein the electric field strength is 100V/cm, and the current density is 200mA/mm 2 。
(4) After the ceramic body A is flash-burned and stabilized, an oscillation pressure with a median value of 150MPa, an amplitude value of 50MPa and a frequency of 2Hz is applied by controlling an upper pressure head and a lower pressure head, the temperature is kept for 10 min, the oscillation force and flash-burning are stopped, and the whisker toughened zirconia ceramic matrix composite is obtained after cooling.
Through detection, the density of the final sample reaches 99.6%, and the hardness reaches 18.5GPa.
Example 4:
the preparation method of the whisker toughened ceramic matrix composite comprises the following steps:
(1) Stirring the Al by ultrasonic for 10h 2 O 3 Whisker 3g and Al 2 O 3 Fully dispersing 7g of powder in 40g of deionized water to obtain ceramic slurry with uniformly distributed whiskers, and sequentially carrying out rotary evaporation, grinding and sieving on the ceramic slurry to obtain ceramic mixed powder of 150 microns;
(2) 4g of the ceramic mixed powder obtained in the step (1) is pressed, and after the pressing forming, a dog-bone-shaped ceramic blank A is obtained;
(3) Placing the ceramic blank A obtained in the step (2) between an upper pressure head and a lower pressure head, heating to a preset temperature of 1000 ℃, then applying a preset electric field intensity on the upper pressure head and the lower pressure head of the ceramic blank, and starting to perform flash burning until the material is completely flash burned; wherein the electric field strength is 200V/cm, and the current density is 5 mA/mm 2 。
(4) When the ceramic body A starts to flash, an oscillation pressure with a median value of 150MPa, an amplitude value of 20MPa and a frequency of 5Hz is applied by controlling an upper pressure head and a lower pressure head, the temperature is kept for 1 min, the oscillation force and the flash are stopped, and the whisker toughened zirconia ceramic matrix composite is obtained after cooling.
Through detection, the density of the final sample reaches 99.8%, and the hardness reaches 22GPa.
Example 5:
the preparation method of the whisker toughened ceramic matrix composite comprises the following steps:
(1) Stirring the Al by ultrasonic for 10h 2 O 3 Fully dispersing 2g of whisker and 28g of zirconia powder in 100g of deionized water to obtain ceramic slurry with uniformly distributed whisker, and sequentially carrying out rotary evaporation, grinding and sieving on the ceramic slurry to obtain ceramic mixed powder of 150 microns;
(2) 4g of the ceramic mixed powder obtained in the step (1) is pressed, and after the pressing forming, a dog-bone-shaped ceramic blank A is obtained;
(3) Sintering the ceramic blank A obtained in the step (2) for 2 hours at 900 ℃ to obtain a pre-pressed sample B with the relative density of 67%;
(4) And placing the pre-pressed sample B in a furnace body, heating the furnace body to the blackbody radiation temperature of 1230 ℃, applying oscillation pressure with the median value of 30 MPa, the amplitude value of 5MPa and the frequency of 1Hz on the pre-pressed sample B by controlling an upper pressure head and a lower pressure head, stopping the oscillation force, and cooling to obtain the whisker toughened zirconia ceramic matrix composite.
Through detection, the density of the final sample reaches 96%, and the hardness reaches 14.7GPa.
Example 6:
the preparation method of the whisker toughened ceramic matrix composite comprises the following steps:
(1) Stirring the Al by ultrasonic for 10h 2 O 3 Fully dispersing 2g of whisker and 28g of zirconia powder in 100g of deionized water to obtain ceramic slurry with uniformly distributed whisker, and sequentially carrying out rotary evaporation, grinding and sieving on the ceramic slurry to obtain ceramic mixed powder of 150 microns;
(2) 4g of the ceramic mixed powder obtained in the step (1) is pressed, and after the pressing forming, a dog-bone-shaped ceramic blank A is obtained;
(3) Placing the ceramic blank A obtained in the step (2) between an upper pressure head and a lower pressure head, heating to a preset temperature of 800 ℃, then applying a preset electric field intensity on the upper pressure head and the lower pressure head of the ceramic blank, and starting to perform flash burning until the material is completely flash burned; wherein the electric field strength is 100V/cm, and the current density is 100 mA/mm 2 。
(4) After the ceramic body A is stable in flash firing, constant pressure of 30 MPa is applied by controlling an upper pressure head and a lower pressure head, the temperature is kept for 10 min, the pressure application and the flash firing are stopped, and the whisker toughened zirconia ceramic matrix composite is obtained after cooling.
Through detection, the density of the final sample reaches 97.8%, and the hardness reaches 15.6GPa.
Example 7: the electric field strength is too high 400
Unlike example 1, the electric field strength used in step 3) was 400V/cm.
Through detection, the density of the final sample reaches 98.5%, and the hardness reaches 16.7GPa.
Example 8: too small an electric field strength of 30
The difference from example 1 is that the electric field strength employed in step 3) is 30V/cm.
The sample is tested to have no flash firing, and the density is not changed and is still 63%.
Example 9: too small a current density of 40
Unlike example 1, the current density used in step 3) was 20mA/mm 2 。
Through detection, the density of the final sample reaches 94%, and the hardness reaches 12.7GPa.
Example 10: the current density is too high 300
Unlike example 1, the current density used in step 3) was 300mA/mm 2 。
Through detection, the density of the final sample reaches 90%, and the hardness reaches 11.4GPa.
Example 11:
unlike example 1, the median magnitude of the oscillating pressure was calculated from the area at 200MPa, the amplitude magnitude at 5MPa and the frequency magnitude at 1Hz.
Through detection, the density of the final sample reaches 97.5%, and the hardness reaches 15.2GPa.
Example 12:
unlike example 1, the median magnitude of the oscillation pressure was calculated from the area at 5MPa, the amplitude at 2MPa, and the frequency at 1Hz.
Through detection, the density of the final sample reaches 96.8%, and the hardness reaches 15GPa.
Example 13:
the difference from example 1 is that the zirconia powder was replaced with SiC powder.
It was found that under the same conditions no flash burn occurred and no change in density occurred, indicating that the process of the present invention is not applicable to all raw material types.
As shown in fig. 1, the scanned graph of the whisker toughened ceramic sample prepared in example 1 has no air holes, which proves that the sample density measured under the condition is higher; as seen in fig. 2, the grain size is 230nm. As can be seen from fig. 3, the whisker toughened ceramic sample prepared in example 5 has pores in a low-pass scan, which demonstrates that the sample obtained under this condition is less dense, and as can be seen from fig. 4, the grain size is 350nm. From fig. 5, it can also be seen that pores still exist in the scanned graph of the whisker toughened ceramic sample prepared in example 6, but the number of pores is smaller than that in fig. 3, which proves that the compactness is improved, but still smaller than that in fig. 1. Thus demonstrating the effectiveness of flash combined oscillation forging.
As can be seen from the above experiments, when the sintering process is completed at the temperature corresponding to the blackbody radiation without applying flash, the required furnace temperature can be found to be greatly increased, and the final sample has very small relative density and very low hardness within the same time of heat preservation.
When the oscillating pressure is not applied and a constant pressure is used, it can be seen that the density of the synthesized sample is lower than that of the synthesized sample under the oscillating pressure in the same time, because the oscillating pressure accelerates the densification process, that is, the sliding process of grain boundaries or the plastic deformation process. This variation is similar to the fatigue process in metallic materials, and has a great promoting effect on the improvement of the compactness and the performance.
When the electric field strength is too high, the power in the process of flash burning is increased, so that too high heat is generated at the contact position of the electrode and the sample, and the sample is damaged. Thereby reducing the compactness and performance of the sample. When the electric field strength is too small, the initial condition of the flash cannot be reached, and the flash cannot occur at this time, so that the density of the sample cannot be improved.
When the current density is too high, vacancies and defects excited by the current are greatly increased, and part of vacancies are accumulated in the interior of the crystal grains to generate air holes, which cannot be removed by plastic deformation or grain boundary sliding, so that the compactness and performance of the sample are reduced. When the current density is too small, the density brought by flash burning is low, and the vacancies excited by the current are small, at the moment, even if oscillation pressure is applied, the densification and deformation processes are controlled by diffusion, and in the densification and deformation processes of diffusion control, the oscillation force cannot play a promoting role, and finally, the density and deformation degree of the sample are mostly brought by flash burning, so the density and performance are low.
When the median value of the oscillation pressure is too small, dislocation or grain boundary slip caused by flash firing cannot be activated, and at this time, densification and deformation processes are still mainly controlled by diffusion, so that the oscillation pressure has little influence on densification and deformation, and the performance is low.
When the median value of the oscillation pressure is too large, the material is deformed to a large extent, and the defects excited by the current are insufficient to regulate the strain caused by the large pressure, a large number of air holes are generated in the sample to adapt to the large deformation, so that the density and the performance of the final sample are reduced.
In the invention, the compactness is tested by an Archimedes drainage method, and the hardness is tested by a microhardness tester.
Finally, it is noted that the above-mentioned embodiments are merely for illustrating the technical solution of the present invention, and that other modifications and equivalents thereof by those skilled in the art should be included in the scope of the claims of the present invention without departing from the spirit and scope of the technical solution of the present invention.
Claims (6)
1. The method for preparing the whisker toughened ceramic matrix composite by dynamic pressure flash firing is characterized by comprising the following steps of:
1) Uniformly mixing the whisker and ceramic powder to prepare ceramic mixed powder; the whisker is SiC whisker or Al 2 O 3 Whisker, zrO 2 One of the whiskers, the ceramic powder is ZrO 2 Powder, al 2 O 3 One of the powders;
2) Pressing the ceramic mixed powder into a ceramic blank;
3) Placing the ceramic blank in a furnace body, heating the furnace body to 500-1200 ℃, applying an electric field to the ceramic blank for flash firing, wherein the electric field strength is 50-300V/cm, and the current density is 60-200 mA/mm 2 Applying oscillation pressure to the upper end and the lower end of the ceramic body while performing flash firing, wherein the median value of the oscillation pressure is calculated according to the area10-150 MPa, the amplitude value is 5-50 MPa, the frequency is 0.5-20 Hz, and the dynamic force assisted flash forging sintering is carried out;
4) And after the heat preservation is carried out for a certain time, stopping the oscillation pressure and the electric field, and cooling to obtain the whisker toughened ceramic matrix composite.
2. The method of manufacturing according to claim 1, characterized in that: the specific steps of the step 1) are as follows: the whisker and the ceramic powder are dispersed in water by ultrasonic to obtain ceramic slurry, and the ceramic slurry is subjected to rotary evaporation, grinding and sieving to obtain ceramic mixed powder, wherein the particle size of the ceramic mixed powder is 150 microns.
3. The preparation method according to claim 2, characterized in that: the whisker comprises: the proportion of the ceramic powder is 5-30%: 70-95% of deionized water, wherein the amount of deionized water is larger than the total amount of whisker and ceramic powder; the ultrasonic dispersion time is 6-48 h.
4. The method of manufacturing according to claim 1, characterized in that: the heat preservation time in the step 4) is 5-30 min.
5. A whisker toughened ceramic matrix composite made by the method of any of claims 1 to 4.
6. The whisker toughened ceramic matrix composite according to claim 5, wherein: the density range of the composite material is 99% -99.8%, and the hardness is 17.5-23.5GPa.
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