Special ceramic material as well as preparation method and application thereof

Abstract

The invention discloses a special ceramic material and a preparation method and application thereof, and belongs to the technical field of special ceramics, the special ceramic material comprises the following raw materials by mass: 40-50 parts of potassium feldspar, 15-25 parts of quartz, 10-20 parts of clay, 8-15 parts of modified silicon carbide whisker, 5-10 parts of boric oxide, 5-10 parts of a stabilizer and 20-25 parts of water, wherein the surface of the modified silicon carbide whisker is coated with a layer of phosphate crystals. The silicon carbide whiskers can help the ceramic material to resist corrosion of a corrosive medium and reduce crack expansion, and cooperate with the boron oxide to improve the compactness of the material, so that the corrosion resistance and mechanical properties of the material are improved. And the surface of the modified silicon carbide whisker is coated with a layer of phosphate crystals, so that the compatibility and dispersity of the modified silicon carbide whisker in a matrix can be improved, the interface bonding between the modified silicon carbide whisker and the ceramic matrix is enhanced, and the phosphate crystals can also be used as a barrier to further improve the corrosion resistance of the ceramic material.

Description

Technical Field

[0001] The present invention belongs to the technical field of special ceramics, and in particular relates to a special ceramic material and a preparation method and application thereof. Background Art

[0002] Special ceramics is a general term for a new type of ceramics that is different from traditional ceramics such as daily-use ceramics, building ceramics, and sanitary ceramics. Special ceramics are mainly made of high-purity artificially synthesized inorganic compounds and are prepared using modern material technology to produce ceramic materials with unique and excellent properties. Ceramics are used in aerospace, automobile manufacturing, electronic equipment, medical equipment, and other fields that have extremely high requirements for material properties, due to their high temperature resistance, wear resistance, and stable chemical properties.

[0003] However, traditional special ceramic materials still have the problems of high brittleness and insufficient toughness that are unique to ceramic materials. They are prone to fracture when subjected to impact or sudden temperature changes, which limits their application in certain engineering fields. In addition, although most ceramic materials have good chemical inertness, they may still suffer from corrosion when they are often exposed to harsh environments with high temperatures, high pressures, and chemical erosion, especially when they are exposed to chloride ions or other corrosive media.

[0004] Therefore, it is of great significance to obtain a ceramic material that can remain stable under harsh conditions, is not easily damaged in low temperature or high stress environments, has good toughness, and exhibits excellent impact resistance and wear resistance. Summary of the invention

[0005] The purpose of the present invention is to provide a special ceramic material and a preparation method and application thereof, so as to solve the problems of unstable corrosion resistance, insufficient toughness and other mechanical properties of ceramic materials in harsh environments.

[0006] The purpose of the present invention can be achieved through the following technical solutions:

[0007] In a first aspect, the present invention provides a special ceramic material, comprising the following raw materials in parts by weight:

[0008] Potassium feldspar 40-50 parts;

[0009] 15-25 parts of quartz;

[0010] 10-20 parts of clay;

[0011] 8-15 parts of modified silicon carbide whiskers;

[0012] 5-10 parts of boron oxide;

[0013] 5-10 parts of stabilizer;

[0014] 20-25 parts water;

[0015] The surface of the modified silicon carbide whisker is coated with a layer of phosphate crystals.

[0016] Preferably, the stabilizer includes a combination of one or more of lanthanum oxide, calcium oxide, manganese oxide, zinc oxide, zirconium oxide, aluminum oxide and magnesium oxide.

[0017] By adopting the above technical solution, new additives including modified silicon carbide whiskers and boron oxide are introduced into the feldspar-based ceramic material to enhance the corrosion resistance and mechanical properties of the obtained special ceramic material, specifically:

[0018] Silicon carbide whiskers have excellent chemical stability. When used as a reinforcing phase of special ceramic materials, they can improve the corrosion resistance of ceramic materials to most acidic and alkaline chemicals. They can also be combined with matrix materials to optimize the microstructure of the obtained special ceramic materials. They use crack deflection and crack bridging matrix to reduce the crack expansion path, thereby improving the mechanical properties of ceramic materials and greatly reducing the possibility of cracks in ceramics, thereby improving the corrosion resistance of materials. Boron oxide is also added to the formula. Boron oxide can fill the gaps between the crystals formed during the sintering process of special ceramic materials, making the materials denser. It works together with modified silicon carbide whiskers to produce a synergistic effect, which can not only improve the mechanical properties of the materials, but also improve the corrosion resistance of the materials.

[0019] In addition, the silicon carbide whiskers of the present invention have been modified and coated with a layer of phosphate crystals on the surface, which can enhance the chemical stability and corrosion resistance of the silicon carbide whiskers, provide an effective protective barrier for ceramic materials, and strengthen the interface bonding between the modified silicon carbide whiskers and the ceramic matrix, thereby improving the density of the internal structure of the obtained ceramic material, reducing the porosity and the number of defects, thereby helping to disperse stress, further reducing the possibility of crack expansion, and improving the long-term stability and mechanical properties of the obtained special ceramic material.

[0020] Preferably, the raw materials for modifying silicon carbide whiskers include silicon carbide whiskers and water-soluble phosphate in a mass ratio of 1:(0.2-0.3).

[0021] Preferably, the diameter of the silicon carbide whisker is 450-550 nm and the length is 10-15 μm.

[0022] Preferably, the water-soluble phosphate includes one or more combinations of diammonium phosphate, disodium hydrogen phosphate, phosphoric acid, diammonium hydrogen phosphate and sodium pyrophosphate.

[0023] Preferably, the modified silicon carbide whiskers are prepared according to the following steps:

[0024] Pretreatment: The silicon carbide whiskers are washed and dried to obtain pretreated silicon carbide whiskers;

[0025] Modification treatment: adding water-soluble phosphate to deionized water, adjusting the solution pH to 4-6, adding pretreated silicon carbide whiskers, immersing at 30-40°C for 15-20h, and finally washing and heat treating to obtain modified silicon carbide whiskers.

[0026] Preferably, the heat treatment temperature is 100-130° C., and the heat treatment time is 5-6 hours.

[0027] Silicon carbide whiskers can improve the microstructure of the ceramic matrix and enhance the corrosion resistance and mechanical properties of special ceramic materials. However, simply adding silicon carbide whiskers does not have a strong reinforcing effect on ceramics. This is because silicon carbide whiskers have a high surface energy and are prone to agglomeration in the ceramic matrix. In addition, in order to maintain the structural characteristics of silicon carbide whiskers, the dispersion cannot be improved by strengthening the ball milling process, resulting in the whiskers not being able to be evenly dispersed, local stress concentration, which will reduce the overall performance and the bonding strength with the matrix material. Moreover, when the silicon carbide whisker content is high, the "bridging" effect between the whiskers will cause the matrix material to contain more free silicon, which will limit the mechanical properties of the material.

[0028] By adopting the above technical scheme, the silicon carbide whiskers are modified. Specifically, the impurities and pollutants on the surface of the silicon carbide whiskers are first removed by pretreatment to reduce the influence of impurities on phosphate crystallization. Further, the pretreated silicon carbide whiskers are immersed in an aqueous solution of phosphate. The phosphate ions in the solution will be preferentially adsorbed on the surface active sites of the silicon carbide whiskers, and can establish a strong connection with the silicon carbide substrate through chemical bonds. Finally, after heat treatment, a layer of phosphate crystals is formed on the surface of the silicon carbide whiskers. Phosphate crystals have high chemical stability and can act as a barrier to further improve the corrosion resistance of special ceramic materials and effectively prevent the erosion of corrosive media.

[0029] Moreover, after being coated with the phosphate layer, the surface properties of the silicon carbide whiskers can be significantly improved, the wettability between the silicon carbide whiskers and the matrix can be improved, the compatibility and dispersibility of the modified silicon carbide whiskers in the matrix can be improved, and uniform dispersion can be achieved more easily during the mixing and sintering process. The unique structural characteristics of the silicon carbide whiskers can be retained, the stress concentration and voids caused by aggregation can be reduced, the structural density can be improved, and the mechanical properties of the special ceramic materials can be enhanced. In addition, phosphates can help fill the pores in the internal structure of ceramic materials, increase the residual density of special ceramic materials, and thus improve the overall mechanical properties.

[0030] As a barrier, the phosphate layer can not only resist the erosion of external corrosive media, but also maintain the excellent properties of silicon carbide whiskers. It can protect the silicon carbide whiskers from releasing excess free silicon, greatly reducing the adverse effects of free silicon on ceramic materials. The final special ceramic material has excellent corrosion resistance and mechanical properties.

[0031] Preferably, the raw material of the special ceramic material also includes 0.5 to 1.5 parts of phosphoserine.

[0032] By adopting the above technical scheme, the modified silicon carbide whiskers can greatly improve the mechanical properties and corrosion resistance of the obtained special ceramic materials. The introduction of the phosphate crystal layer can help improve the dispersion and stability of the silicon carbide whiskers. However, the introduction of the phosphate crystal layer will introduce a new crystalline phase on the basis of the original ceramic matrix, which will reduce the size of the grains in the special ceramic materials during the sintering process or cause changes in the morphology of the grains, thereby affecting the mechanical properties of the special ceramic materials.

[0033] Therefore, the raw materials of the present invention can also be added with phosphoserine. As a phosphorus-containing organic substance, phosphoserine can be adsorbed at the newly formed grain boundaries in the early stage of ball milling and sintering by combining with the surface active sites in the matrix, thereby changing the energy state of the grain boundaries, inhibiting the abnormal growth of grains, helping to maintain uniform growth of grains, and promoting fine grain strengthening effects, thereby improving the mechanical properties of the obtained special ceramic materials.

[0034] In addition, phosphoserine can participate in the formation of complex networks and composite phases between ceramic matrices, optimize the microstructure of ceramic materials, fill grain boundary areas, reduce internal porosity, and help obtain special ceramic materials with dense structure, strong impermeability, corrosion resistance and high toughness.

[0035] In a second aspect, the present invention provides a method for preparing special ceramics, comprising the following process steps:

[0036] S1. Weigh the raw materials of special ceramic materials according to the corresponding mass parts, mix them and perform wet ball milling to obtain a premix;

[0037] S2. The premix is ​​sieved, and then sintered at a high temperature of 1300-1500° C. for 1-2 hours under vacuum conditions, and a special ceramic material is obtained after cooling.

[0038] More preferably, the wet ball milling time is 15 to 20 hours.

[0039] More preferably, the premix is ​​sieved twice, the first time through a 400 mesh sieve and the second time through a 120 mesh sieve.

[0040] More preferably, in step S1, not adding phosphoserine can also solve the technical problem that the present invention aims to solve and obtain the desired technical effect.

[0041] In a third aspect, the present invention provides an application of a special ceramic material, which can be used for any one of capacitors, packaging materials for microelectronic devices, carriers for exhaust gas catalytic devices, reactor linings, and pump and valve components.

[0042] Beneficial effects of the present invention:

[0043] 1. The raw materials of the special ceramic material obtained by the present invention introduce two reinforcing phases, namely, modified silicon carbide whiskers and boron oxide. Silicon carbide whiskers can help the ceramic material resist the erosion of corrosive media and reduce crack expansion. At the same time, they cooperate with boron oxide to improve the compactness of the obtained special ceramic material, thereby improving the corrosion resistance and mechanical properties of the material. In addition, the surface of the modified silicon carbide whisker of the present invention is also coated with a layer of phosphate crystals, which can improve the compatibility and dispersibility of the modified silicon carbide whisker in the matrix, strengthen the interface bonding between the modified silicon carbide whisker and the ceramic matrix, and can also serve as a barrier to further improve the corrosion resistance of the ceramic material.

[0044] 2. The raw materials of the special ceramic material of the present invention also include phosphoserine, which can optimize the crystallization process of special ceramics, inhibit the abnormal growth of grains, and help form a fine and uniform grain structure, thereby improving the mechanical properties of special ceramic materials. It can also improve the microstructure of the ceramic matrix, reduce the internal porosity, and obtain a special ceramic material with a dense structure, excellent corrosion resistance and mechanical properties. DETAILED DESCRIPTION

[0045] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0046] Preparation Example

[0047] Preparation Example 1: A modified silicon carbide whisker is prepared according to the following method:

[0048] 10 g of silicon carbide whiskers (average diameter of 500 nm, average length of 12 μm) were taken, washed alternately with anhydrous ethanol and deionized water, and then dried at 60° C. to obtain pretreated silicon carbide whiskers;

[0049] Take 2.5g of ammonium dihydrogen phosphate and add it to deionized water to prepare a phosphate aqueous solution with a mass fraction of 35%, adjust the solution pH to 5, add 10g of pretreated silicon carbide whiskers, soak at 35°C for 20h, then filter, wash with deionized water 3 times, and heat treat at 120°C for 5h to obtain modified silicon carbide whiskers.

[0050] Preparation Example 2, a modified silicon carbide whisker, is different from Preparation Example 1 only in that the amount of ammonium dihydrogen phosphate added is 2 g.

[0051] Preparation Example 3, a modified silicon carbide whisker, is different from Preparation Example 1 only in that the amount of ammonium dihydrogen phosphate added is 3 g.

[0052] Preparation Example 4, a modified silicon carbide whisker, is different from Preparation Example 1 only in that the amount of ammonium dihydrogen phosphate added is 1 g.

[0053] Preparation Example 5, a modified silicon carbide whisker, is different from Preparation Example 1 only in that the amount of ammonium dihydrogen phosphate added is 4 g.

[0054] Example

[0055] Example 1, a special ceramic material is prepared according to the following process steps:

[0056] S1. Weigh 45 parts by mass of potassium feldspar, 20 parts by mass of quartz, 15 parts by mass of clay, 12 parts by mass of the modified silicon carbide whisker prepared in Preparation Example 1, 6 parts by mass of boron oxide, 8 parts by mass of zinc oxide and 23 parts by mass of water, mix them evenly and then wet-mill them to obtain a premix, wherein the wet-milling speed is 50 r / min and the time is 15 h;

[0057] S2. The premix obtained above is first passed through a 400-mesh sieve and then through a 120-mesh sieve. The obtained mixture is sintered at 1350° C. for 1.5 h under vacuum conditions and cooled to obtain a special ceramic material.

[0058] Embodiment 2 to Embodiment 3 are special ceramic materials, which differ from Embodiment 1 only in that the raw material ratio of the special ceramic material is adjusted, as shown in Table 1:

[0059] Table 1 Special ceramic material formula table of embodiment 1 to embodiment 3

[0060] Example 1 Example 2 Example 3 Potassium feldspar / part 45 40 50 Quartz / piece 20 25 15 Clay / part 15 10 20 Modified silicon carbide whisker / part 12 8 15 Boron oxide / part 6 10 5 Zinc oxide / part 8 5 10 Water / part 23 20 25

[0061] Among them, Example 2 and Example 3 use the modified silicon carbide whiskers obtained in Example 1 for uniform preparation.

[0062] Example 4 is a special ceramic material, which is different from Example 1 only in that the modified silicon carbide whiskers prepared in Preparation Example 1 are replaced by an equal amount of modified silicon carbide whiskers prepared in Preparation Example 2.

[0063] Example 5 is a special ceramic material, which is different from Example 1 only in that the modified silicon carbide whiskers prepared in Preparation Example 1 are replaced by an equal amount of modified silicon carbide whiskers prepared in Preparation Example 3.

[0064] Example 6, a special ceramic material, is different from Example 1 only in that the modified silicon carbide whiskers prepared in Preparation Example 1 are replaced by an equal amount of modified silicon carbide whiskers prepared in Preparation Example 4.

[0065] Example 7, a special ceramic material, is different from Example 1 only in that the modified silicon carbide whiskers prepared in Preparation Example 1 are replaced by an equal amount of modified silicon carbide whiskers prepared in Preparation Example 5.

[0066] Example 8, a special ceramic material is prepared according to the following process steps:

[0067] S1. Weigh 45 parts by mass of potassium feldspar, 20 parts by mass of quartz, 15 parts by mass of clay, 12 parts by mass of the modified silicon carbide whisker prepared in Preparation Example 1, 6 parts by mass of boron oxide, 8 parts by mass of zinc oxide, 1 part by mass of phosphoserine and 23 parts by mass of water, mix them evenly and then wet-mill them to obtain a premix, wherein the wet-milling speed is 50 r / min and the time is 15 h;

[0068] S2. The premix obtained above is first passed through a 400-mesh sieve and then through a 120-mesh sieve. The obtained mixture is sintered at 1350° C. for 1.5 h under vacuum conditions and cooled to obtain a special ceramic material.

[0069] Example 9, a special ceramic material, is different from Example 8 only in that the added amount of phosphoserine is 0.5 parts.

[0070] Example 10, a special ceramic material, is different from Example 8 only in that the added amount of phosphoserine is 1.5 parts.

[0071] Example 11, a special ceramic material, is different from Example 8 only in that the added amount of phosphoserine is 2 parts.

[0072] Comparative Example

[0073] Comparative Example 1 is a special ceramic material, which is different from Example 1 only in that the added amount of the modified silicon carbide whisker prepared in Preparation Example 1 is 5 parts.

[0074] Comparative Example 2 is a special ceramic material, which is different from Example 1 only in that the added amount of the modified silicon carbide whisker prepared in Preparation Example 1 is 20 parts.

[0075] Comparative Example 3 is a special ceramic material, which is different from Example 1 only in that the modified silicon carbide whiskers prepared in Preparation Example 1 are replaced by an equal amount of silicon carbide whiskers (with an average diameter of 500 nm and an average length of 12 μm).

[0076] Comparative Example 4 is a special ceramic material, which is different from Example 1 only in that the modified silicon carbide whiskers prepared in Preparation Example 1 are not added.

[0077] Comparative Example 5 is a special ceramic material, which is different from Example 1 only in that boron oxide is not added.

[0078] Performance testing

[0079] 1. Mechanical properties test: According to the relevant records in GB / T 14389-93 "Test method for impact toughness of engineering ceramics", the impact toughness (KJ / m 2 ) for testing;

[0080] 2. Corrosion resistance test: The special ceramic materials obtained in the examples and comparative examples were completely immersed in seawater, and the mass loss rate of the ceramic materials was tested after 90 days.

[0081] The above test results are shown in Table 2:

[0082] Table 2 Performance test results

[0083]

[0084] According to Table 2, in combination with Example 1, Example 6, Example 7 and Comparative Example 3, it can be seen that the impact toughness of Example 6, Example 7 and Comparative Example 3 has decreased, and the mass loss rate has increased, among which the change in Comparative Example 3 is more obvious. The reason is that Example 6, Example 7 and Comparative Example 3 mainly adjust the amount of phosphate added in the preparation process of modified silicon carbide whiskers, among which the amount of water-soluble phosphate added is reduced in Example 6, and the phosphate crystals on the surface of the modified silicon carbide whiskers obtained are correspondingly reduced, the barrier effect formed is weakened, the dispersibility of the silicon carbide whiskers and the bonding force between the silicon carbide whiskers and the ceramic matrix are reduced, resulting in a decrease in the corrosion resistance and mechanical properties of the obtained special ceramic materials; the silicon carbide whiskers added in Comparative Example 3 have not been subjected to phosphate crystallization coating modification treatment, so the performance of the special ceramic material has been more significantly reduced. In Example 7, the amount of water-soluble phosphate added is increased, which will lead to the formation of excessive phosphate crystals on the surface of the silicon carbide whiskers, weakening the bonding strength between the silicon carbide whiskers and the ceramic matrix. In addition, excessive phosphate crystals will reduce the chemical stability of the silicon carbide whiskers themselves, which is not conducive to improving the corrosion resistance.

[0085] Combining Example 1, Example 8 to Example 11, it can be seen that the impact toughness of Example 8 is increased compared with Example 1, and the mass loss rate is reduced. The impact toughness and mass loss rate of Example 9 and Example 10 are not significantly changed compared with Example 8. The impact toughness of Example 11 is reduced compared with Example 8, and the mass loss rate is increased. The reason is that the addition of phosphoserine in the special ceramic material in Example 8 can well improve the grain change and uneven growth of the special ceramic material caused by the addition of modified silicon carbide whiskers, and can help optimize the microstructure of the ceramic material, reduce the internal porosity, thereby improving the density of the material, and obtaining a ceramic material with enhanced mechanical properties and corrosion resistance. The difference between Example 9 and Example 10 compared with Example 8 is only that the addition amount of phosphoserine is adjusted within the required range, indicating that changing the addition amount of phosphoserine within the required range has no significant effect on the performance of the obtained special ceramic material. Compared with Example 8, Example 11 adds excessive phosphoserine. Phosphoserine contains a large number of polar groups, including amino, carboxyl and other functional groups, which are prone to cause unnecessary side reactions with other components of the ceramic matrix during high-temperature sintering, affecting the overall chemical stability and the mechanical properties of the obtained ceramic material. In addition, during the processing, excessive phosphoserine will increase the viscosity of the obtained premix, bringing difficulties to the subsequent molding process.

[0086] Combining Example 1, Comparative Example 1, Comparative Example 2 and Comparative Example 4, it can be seen that the impact toughness of Comparative Example 1, Comparative Example 2 and Comparative Example 4 is reduced compared with that of Example 1, and the mass loss rate is increased. The reason is that the amount of modified silicon carbide whiskers added is adjusted in Comparative Example 1, Comparative Example 2 and Comparative Example 4. Among them, the amount of modified silicon carbide whiskers added is reduced in Comparative Example 1, and the content of modified silicon carbide whiskers is reduced, so the enhancement effect on the corrosion resistance of the ceramic matrix is ​​reduced, and the optimization effect on the crack propagation path inside the ceramic material is also reduced. The possibility of cracks in the ceramic will increase, and the corrosive medium will be more likely to erode the internal structure of the ceramic, and the synergistic effect with boron oxide is reduced, so that the mechanical properties and corrosion resistance of the special ceramic material finally obtained are reduced. In Comparative Example 4, no modified silicon carbide whiskers are added, and the mechanical properties and corrosion resistance of the material are more obviously reduced. In Comparative Example 2, an excessive amount of modified silicon carbide whiskers is added. The excessive whisker structure will induce stress concentration, making the obtained special ceramic material more likely to crack and expand when subjected to external loads, thereby resulting in a decrease in the mechanical properties of the material; and the addition of excessive silicon carbide whiskers will also affect the thermal stability of the ceramic material. Since silicon carbide whiskers themselves have high thermal conductivity and can accelerate heat transfer, when the whisker content is excessive, the heat transfer will become uneven, which not only affects the thermal stability of the ceramic material but also easily generates internal stress that is difficult to eliminate, forming holes at the grain boundaries, resulting in performance degradation.

[0087] Combining Example 1 and Comparative Example 5, it can be seen that the impact toughness of Comparative Example 5 is reduced and the mass loss rate is increased compared with Example 1. The reason is that no boron oxide is added in Comparative Example 5, which cannot help fill the pores between crystals inside the ceramic material, resulting in a decrease in the density of the obtained special ceramic material, and the lack of boron oxide will increase the stress accumulation inside the material caused by temperature changes, which is not conducive to the improvement of the mechanical properties and corrosion resistance of the material.

[0088] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0089] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A special ceramic material, characterized in that: Including the following raw materials by mass: Potassium feldspar 40-50 parts; 15-25 parts of quartz; 10-20 parts of clay; 8-15 parts of modified silicon carbide whiskers; 5-10 parts of boron oxide; 5-10 parts of stabilizer; 20-25 parts water; The surface of the modified silicon carbide whisker is coated with a layer of phosphate crystals.

2. The special ceramic material according to claim 1, characterized in that: The raw materials of the modified silicon carbide whisker include silicon carbide whisker and water-soluble phosphate in a mass ratio of 1:(0.2-0.3).

3. The special ceramic material according to claim 2, characterized in that: The silicon carbide whisker has a diameter of 450-550 nm and a length of 10-15 μm.

4. The special ceramic material according to claim 2, characterized in that: The water-soluble phosphate includes one or more combinations of diammonium phosphate, disodium hydrogen phosphate, phosphoric acid, diammonium hydrogen phosphate and sodium pyrophosphate.

5. The special ceramic material according to claim 2, characterized in that: The modified silicon carbide whisker is prepared according to the following steps: Pretreatment: The silicon carbide whiskers are washed and dried to obtain pretreated silicon carbide whiskers; Modification treatment: adding water-soluble phosphate to deionized water, adjusting the solution pH to 4-6, adding pretreated silicon carbide whiskers, immersing at 30-40°C for 15-20h, and finally washing and heat treating to obtain modified silicon carbide whiskers.

6. The special ceramic material according to claim 5, characterized in that: The heat treatment temperature is 100-130° C., and the heat treatment time is 5-6 hours.

7. The special ceramic material according to claim 1, characterized in that: The raw materials of the special ceramic material also include 0.5 to 1.5 parts of phosphoserine.

8. The special ceramic material according to claim 1, characterized in that: The stabilizer includes a combination of one or more of lanthanum oxide, calcium oxide, manganese oxide, zinc oxide, zirconium oxide, aluminum oxide and magnesium oxide.

9. A method for preparing a special ceramic material according to any one of claims 1 to 8, characterized in that: The process steps include: S1. Weigh the raw materials of special ceramic materials according to the corresponding mass parts, mix them and perform wet ball milling to obtain a premix; S2. The premix is ​​sieved, and then sintered at a high temperature of 1300-1500° C. for 1-2 hours under vacuum conditions, and a special ceramic material is obtained after cooling.

10. An application of the special ceramic material according to any one of claims 1 to 8, characterized in that: The special ceramic material can be used for any of capacitors, packaging materials for microelectronic devices, carriers for tail gas catalytic devices, reactor linings, and pump and valve components.

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