High-strength ceramic and its forming process

Abstract

The application discloses high-strength ceramic and a forming process thereof, and belongs to the technical field of ceramic materials. The ceramic comprises the following components in proportion by mass: 3-10 parts of reinforcing material, 40-45 parts of kaolin, 25-40 parts of quartz sand, 8-15 parts of aluminum oxide, 3-7 parts of nano toughening agent and 1-3 parts of pigment. The reinforcing material significantly improves heat resistance and interfacial bonding force through isotopic effect of deuterium groups and aryl steric hindrance. The forming process comprises gradient mixing, ultrasonic-assisted dispersion, high-pressure homogenization and a staged solidification and sintering process, and introduces quenching treatment to improve surface density. Meanwhile, the raw material dispersion degree and energy consumption efficiency are optimized, the problems of low strength and complex process of traditional ceramics are solved, and the high-strength ceramic is applied to special materials for biological medical additive manufacturing.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of ceramics, in particular to a high-strength ceramic and its forming process. BACKGROUND

[0002] In the technical field of ceramic materials, traditional ceramic materials have many shortcomings in strength, toughness and processing performance, which limit their widespread use in high-end applications. In the prior art, the strength and toughness of ceramic materials are usually low, which is difficult to meet the use requirements in complex mechanical environments, such as the application in the biological medical field such as artificial joints, dental restorations and orthopedic implants. In addition, the preparation process of traditional ceramic materials is complex, the energy consumption is high, and the cost is expensive, which is difficult to realize efficient production and large-scale application.

[0003] The insufficient strength and toughness of traditional ceramic materials is one of the main technical bottlenecks. Due to the brittle nature of ceramic materials, they are prone to fracture or failure when subjected to high stress or complex mechanical load. In the prior art, although the toughness of ceramics can be improved to some extent by adding toughening agents or optimizing the sintering process, these methods often cannot simultaneously improve the strength and toughness.

[0004] The preparation process of traditional ceramic materials is complex and energy-consuming. In the prior art, the preparation of ceramic materials usually requires high-temperature sintering and multiple processing, resulting in long production cycle, high energy consumption, and easy introduction of micro-cracks and pores, etc. Defects further reduce the mechanical properties of the material. In addition, the traditional process is difficult to realize the complex structure design and accurate forming of ceramic materials, which limits its application in emerging technologies such as additive manufacturing.

[0005] In summary, the ceramic materials in the prior art have significant shortcomings in strength, toughness, process complexity, energy consumption and cost, and an innovative solution is needed to comprehensively improve performance, simplify process and reduce energy consumption. SUMMARY

[0006] The present application aims to provide a high-strength ceramic and its forming process to solve the problems of insufficient strength, complex process, high energy consumption and high cost in the prior art. By optimizing the composition and improving the preparation process, the present application can significantly improve the strength and toughness of the ceramic, while reducing the production cost and energy consumption.

[0007] The purpose of the present application is to solve the problems existing in the prior art, and to provide a high-strength ceramic, the mass ratio of the components of which is: 3-10 parts of reinforcing material, 40-45 parts of kaolin, 25-40 parts of quartz sand, 8-15 parts of alumina, 3-7 parts of toughening agent, and 1-3 parts of pigment.

[0008] The structure of the reinforcing material is a compound represented by Formula I;

[0009]

[0010] A1in the formula I is selected from the group consisting of: hydrogen, methyl, deuterated methyl;

[0011] Ar1in the formula I is selected from the group consisting of: C6-C 24 aryl;

[0012] R1in the formula I is selected from the group consisting of: hydrogen, C1-C5alkyl, C1-C5deuterated alkyl, C6-C 10 aryl, C4-C 10 heteroaryl, C6-C 10 deuterated aryl;

[0013] or R1in the formula I is selected from the group consisting of: C6-C 10 aryl substituted with C1-C5alkyl, C4-C 10 heteroaryl substituted with C1-C5alkyl, C6-C 10 deuterated aryl substituted with C1-C5alkyl.

[0014] Further, the C6-C 24 aryl is selected from the group consisting of: phenyl, naphthyl, anthryl, any one of which.

[0015] Further, the C6-C 10 aryl is selected from the group consisting of: phenyl, naphthyl, any one of which;

[0016] The C4-C 10 heteroaryl is selected from the group consisting of: furanyl, thienyl, any one of which;

[0017] The C6-C 10 deuterated aryl is selected from the group consisting of: deuterated phenyl, deuterated naphthyl, any one of which;

[0018] The C1-C5alkyl is selected from the group consisting of: methyl, ethyl, tert-butyl, propyl, any one of which;

[0019] The C1-C5deuterated alkyl is selected from the group consisting of: deuterated methyl, deuterated ethyl, deuterated tert-butyl, deuterated propyl, any one of which.

[0020] Further, the toughening agent is selected from the group consisting of: nano-silica and / or nano-zirconium oxide.

[0021] Further, the kaolin has a SiO2content: 45-55%, an Al2O3content: 30-40%, a Fe2O3and TiO2content ≤ 0.5%, a particle size D 50 ≤ 10 μm.

[0022] Furthermore, the pigment is selected from one or more of zirconium oxide (ZrO2), silicon nitride (Si3N4), and silicon carbide (SiC).

[0023] Furthermore, the SiO2 content in the quartz sand is ≥99.5%, the Al2O3 content is ≤0.2%, the alkali metal oxide content is ≤0.1%, and the particle size D50 is ≤50 μm.

[0024] Furthermore, the reinforcing material is selected from any one compound of reinforcing material 1 to reinforcing material 16:

[0025]

[0026]

[0027] Furthermore, the synthesis steps of the reinforcing material are:

[0028]

[0029] P1. NBS (2.4 eq) was added to a solution of raw material 1 (1.0 eq) in DCM (8-10 times the mass of raw material 1), and the mixture was stirred at 25° C. for 16 hours. The reaction was monitored by TLC until completion, filtered, and the filter was washed with a saturated aqueous NaHCO 3 solution. The organic phase was washed with brine, dried over anhydrous MgSO 4 , filtered, and concentrated in vacuo to obtain a white solid 1. The white solid 1 (1.0 eq) was placed in dry THF (8-10 times the mass of the white solid 1), cooled to -70° C., n-butyl lithium (2.12 eq) was added dropwise, and after the addition was complete, it was stirred for 1 hour. Triisopropyl borate (3.0 eq) was added dropwise, and after the addition was complete, it was naturally warmed to room temperature. The reaction was allowed to proceed overnight, and water was slowly added to quench the n-butyl group. The pH of the system was adjusted to neutral with a 0.1 mol / L aqueous HCl solution. The organic phase was extracted and retained. The organic phase was dried over anhydrous MgSO 4 , filtered, and concentrated in vacuo. It was purified by a silica gel purification column to obtain intermediate 1.

[0030] P2. Under a nitrogen atmosphere, intermediate 1 (1 eq), raw material 2 (2.2 eq), and anhydrous potassium carbonate (5.0 eq) were added to the phase system in sequence, dissolved in a mixed solution of toluene, ethanol, and water (volume ratio 2:1:1) (the mass was 8-10 times the mass of intermediate 1), and the nitrogen was replaced twice. Under nitrogen protection, tetrakis(triphenylphosphine)palladium (6% eq) was added to the phase system, and the nitrogen was replaced twice. The reaction was heated to 75°C and refluxed for 10 hours. The heating was turned off, and the mixture was cooled to room temperature and allowed to stand for separation. The aqueous phase was extracted twice with ethyl acetate, the organic phases were combined, washed three times with water, spin-dried, and subjected to column chromatography using a mixture of petroleum ether and dichloromethane as an eluent to obtain intermediate 2.

[0031] P3. Under the protection of nitrogen, intermediate 2 (1.0 eq) and raw material 3 (2.2 eq) are dissolved in a toluene solution (8-10 times the mass of intermediate 2), sodium tert-butoxide (4.0 eq) is added, tris(dibenzylideneacetone)dipalladium (0.02 eq), tri-tert-butylphosphine (0.12 eq), stirred uniformly, heated to 120°C, and refluxed for 12 h; after the reaction is completed, the temperature is slightly lowered, diatomite is used for filtration to remove the salt and catalyst, the filtrate is cooled to room temperature, washed with water three times, the organic phase is retained, then the aqueous phase is extracted with ethyl acetate; the combined organic phase is dried with anhydrous magnesium sulfate, and the solvent is removed using a rotary evaporator; recrystallized in petroleum ether / ethanol, filtered, the filter cake is washed with petroleum ether several times, and placed in a 60°C oven for drying for 7 h to obtain the reinforcing material.

[0032] Further, the numbering of the carbon atoms on the anthracene ring in the raw material 1 is shown in the structure of formula II:

[0033]

[0034] The raw material 1 (formula II) is composed of multiple symmetrically arranged six-membered rings, connected by carbon-carbon bonds between the rings, and contains multiple oxygen (O) and amino (NH) substituents. The amino group (HN) is located at the ortho position of the left ring, significantly activating the electrophilic reactivity of the 2nd position, while the oxygen atoms are distributed on other rings. This symmetrical structure and the positioning of the substituents together determine that the bromination reaction preferentially occurs at the 2nd position, and then the electron-withdrawing effect of bromine further promotes the lithiation-boronation reaction at the ortho position, ultimately forming the target intermediate 1.

[0035] The selection of hydrogen, tert-butyl, and deuterated tert-butyl in the structure of the reinforcing material directly affects the polarity, thermal stability, and interfacial bonding ability of the reinforcing material with inorganic fillers. Deuterated methyl (-CD3) can reduce the C-D bond vibration energy through isotopic effect, improving the thermal decomposition resistance of the reinforcing material during high-temperature sintering. The bulky aryl group (such as anthracene) provides a steric hindrance effect, inhibiting the disordered movement of the reinforcing material molecular chain at high temperatures, thereby enhancing the dimensional stability of the ceramic green body.

[0036] A forming process of high-strength ceramics, comprising the following steps:

[0037] S1. Pre-dispersion treatment: the reinforcing material is pre-mixed with an organic solvent to form a reinforcing material mother liquor;

[0038] S2. Gradient mixing: the reinforcing material mother liquor is added to the dry powder of kaolin, quartz sand, and alumina three times, mixed and dispersed, the mixing temperature is controlled at 40-50°C, and the mixture is obtained;

[0039] S3. High pressure homogenization: the mixture is stirred and homogenized at a pressure of 60-80 MPa, so that the particle size D 50 ≤ 2 μm;

[0040] S4. Solidification: solidification at 60-80°C for 3-5 hours, then heating at a rate of 5-10°C / min to 600-800°C for 1 hour, and then sintering at a rate of 5-10°C / min to 1250-1300°C for 2 hours.

[0041] Further, the organic solvent is selected from tetrahydrofuran and / or toluene; the mass ratio of the reinforcing material to the organic solvent is 1:(3-5); and the temperature for forming the reinforcing material mother liquor is 50-60°C.

[0042] Further, in the S2, ultrasonic assisted dispersion is applied simultaneously when the reinforcing material mother liquor is mixed and dispersed, the frequency is 30-40 kHz, and the power density is 0.5 W / cm 3 .

[0043] Further, after the sintering at 1250-1300°C for 2 hours in the S4, quenching treatment is added: the ceramic is cooled from 1250°C to 600°C at a rate of ≥50°C / min, so as to improve the surface density.

[0044] Further, after the homogenization treatment in the S3, vacuum degassing is performed, the vacuum degree is ≤-0.095 MPa, and the maintaining time is 20-30 minutes.

[0045] Further, the polar functional groups (such as carbonyl groups) in the reinforcing material coat the surfaces of the kaolin / quartz sand particles through hydrogen bonds and van der Waals forces, so as to reduce the interface energy difference and achieve nanoscale dispersion. In the solidification stage S4, the reinforcing material forms an interpenetrating network structure: the π-π stacking of the aryl groups enhances the rigidity of the network, and the aluminum oxide particles are dispersed in the network as physical crosslinking points; the C-D bond vibration frequency of the deuterated alkyl groups is low, so as to reduce the molecular chain rupture during high-temperature sintering and improve the network integrity retention rate by more than 30%. In the high-temperature sintering stage: the carbonization of the reinforcing material forms a nanocarbon skeleton, which reacts with the aluminum oxide to improve the fracture toughness of the ceramic. In the absence of the reinforcing material, the direct contact between the kaolin particles leads to a reduction of 70% in the sintering neck formation efficiency, and the micron-sized pores (diameter >5 μm) existing in the quartz sand-aluminum oxide interface also cause a decrease in the mechanical properties.

[0046] The high-strength ceramic is used for manufacturing special ceramic products, such as ceramic valves, ceramic cylinder valve pieces, functional ceramics (such as piezoelectric and thermoelectric ceramics), and green special refractory ceramics.

[0047] The high-strength ceramic described in the application can meet the requirements of high pressure and high wear working conditions through the heat resistance enhanced by deuterated groups and the interpenetrating structure of nanocarbon skeleton. The bending strength reaches 189.8 MPa, the elastic modulus is 39.8 GPa, and the mechanical impact during valve opening and closing can be withstood. The dense surface (porosity <0.5%) formed by the rapid cooling process can reduce the risk of medium penetration. The aryl steric hindrance effect in the reinforcing material makes the material maintain dimensional stability at a high temperature of 300℃, which is better than traditional zirconia valve ceramic.

[0048] The synergistic effect of alumina and nanosilica in the ceramic described in the application provides a basis for piezoelectric performance: the high-pressure homogenization process makes the grain size ≤2μm, promoting polarization orientation; the low vibration energy characteristics of C-D bond of deuterated alkyl can reduce dielectric loss. The heterogeneous interface formed by gradient sintering process enhances the thermoelectric conversion efficiency, and the Seebeck coefficient reaches 220μV / K after sintering at 1200℃, which is suitable for high-temperature sensor manufacturing. The carbonization reaction of deuterated reinforced material in kaolin-quartz sand system optimizes the formation of mullite-silicon carbide composite refractory phase, and the refractoriness reaches 1790℃. The surface compressive stress generated by rapid cooling process is higher than that of traditional refractory materials.

[0049] In summary, the material described in the application breaks through the technical problem of mutual exclusion of traditional ceramic strength and toughness through the synergy of chemical bond design (deuterium effect) and process innovation (gradient sintering + rapid cooling). In the field of industrial special ceramics, its 189.8MPa bending strength can bear the working pressure of 50MPa of the valve; the elastic modulus of 39.8GPa ensures the stability of the high-frequency response of the piezoelectric element; the nanocarbon skeleton structure makes the thermal conductivity of the refractory material reach 35W / (m·K), realizing the unity of high strength and functional characteristics, and meeting the stringent requirements of high-end equipment manufacturing on special ceramics.

[0050] Compared with the prior art, the beneficial effects of the application are:

[0051] 1. Significantly improve the strength and toughness of the ceramic: by optimizing the composition and improving the preparation process, the bending strength, elastic modulus and Vickers hardness of the ceramic are significantly improved, especially when deuterated reinforcing materials are used.

[0052] 2. Reduce production cost and energy consumption: the process optimization such as gradient mixing, high-pressure homogenization and rapid cooling treatment reduces energy consumption and production time, and improves the density and surface quality of the material, thereby reducing the production cost.

[0053] 3. Simple process and high stability: the preparation process of the application is simple and easy to operate, which ensures the dimensional stability and interface bonding capacity of the ceramic body, and avoids the common problems of microcracks and pores in traditional processes.

[0054] 4. Performance optimization and diversification: The present application realizes the diversification and optimization of ceramic performance by adjusting the structure of reinforcing materials (such as deuterated methyl, aryl, etc.) and process parameters (such as quenching rate, dispersion method, etc.). For example, the quenching process improves the surface density and reduces microcracks, and the nano-silica toughening agent and high-pressure homogenization process significantly improve the elastic modulus and hardness. BRIEF DESCRIPTION OF DRAWINGS

[0055] Figure 1 Synthesis steps of the reinforcing material described in the present application. DETAILED DESCRIPTION

[0056] The technical solutions of the present application will be described clearly and completely below in combination with the drawings in the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0057] NBS in the present application is N-bromosuccinimide; DCM is dichloromethane; NaHCO3 is sodium bicarbonate; TLC is thin layer chromatography; MgSO4 is magnesium sulfate; HCl is hydrochloric acid; HPLC is high performance liquid chromatography; MS is mass spectrometry; eq is equivalent; CAS registration number is the compound number recorded in SciFinder database; 1 HNMR is nuclear magnetic resonance hydrogen spectrum.

[0058] A high-strength ceramic, wherein the mass ratio of the reinforcing material is: 3 parts, 4 parts, 5 parts, 6 parts, 7 parts, 8 parts, 9 parts, 10 parts.

[0059] A high-strength ceramic, wherein the mass ratio of kaolin is: 40 parts, 41 parts, 42 parts, 43 parts, 44 parts, 45 parts.

[0060] A high-strength ceramic, wherein the mass ratio of quartz sand is: 25 parts, 26 parts, 27 parts, 28 parts, 29 parts, 30 parts, 31 parts, 32 parts, 33 parts, 34 parts, 35 parts, 36 parts, 37 parts, 38 parts, 39 parts, 40 parts.

[0061] A high-strength ceramic, wherein the mass ratio of alumina is: 8 parts, 9 parts, 10 parts, 11 parts, 12 parts, 13 parts, 14 parts, 15 parts.

[0062] A high-strength ceramic, wherein the mass ratio of the toughening agent is: 3 parts, 4 parts, 5 parts, 6 parts, 7 parts.

[0063] A high-strength ceramic, wherein the mass ratio of the pigment is: 1 part, 2 parts, 3 parts.

[0064] Example 1-1

[0065] Synthesis of Reinforcing Material 1:

[0066]

[0067] wherein the CAS Registry Number of Raw Material 1 is: 103551-76-4; the CAS Registry Number of Raw Material 2 is: 507-19-7; and the CAS Registry Number of Raw Material 3 is: 3972-65-4.

[0068] P1. NBS (27.01 g, 2.4 eq) was added to a solution of Raw Material 1 (20.00 g, 1.0 eq) in DCM (200 g), the mixture was stirred at 25 °C for 16 hours, the reaction was monitored by TLC until completion, filtered and the filter was washed with saturated NaHC03 aqueous solution, the organic phase was washed with brine, dried over anhydrous MgS04, filtered and concentrated in vacuo to give white solid 1, which was dissolved in dry THF (250 g), cooled to -70 °C, n-butyllithium (3.56 g, 2.12 eq) was added dropwise, after the addition was completed, stirred for 1 h, triisopropyl borate (29.61 g, 3.0 eq) was added dropwise, after the addition was completed, the temperature was allowed to rise to room temperature naturally, the reaction was allowed to proceed overnight, water was added slowly to quench the n-butyllithium, the pH of the system was adjusted to neutral with 0.1 mol / L HC1 aqueous solution, the organic phase was reserved after extraction, dried over anhydrous MgS04, filtered and concentrated in vacuo, purified by a silica gel purification column to give Intermediate 1 (15.90 g, HPLC showed a purity of 99.0%).

[0069] P2. Under a nitrogen atmosphere, Intermediate 1 (15.90 g, 1 eq), Raw Material 2 (11.87 g, 2.2 eq), anhydrous potassium carbonate (27.20 g, 5.0 eq) were added to the phase system in turn, dissolved in a mixed solution of toluene, ethanol, water (volume ratio 2:1:1) (150 g), replaced with nitrogen twice, under the protection of nitrogen, tetrakis(triphenylphosphine)palladium (2.73 g, 6% eq) was added to the phase system, replaced with nitrogen twice, heated to 75 °C and refluxed for 10 hours, the heating was turned off, cooled to room temperature, and allowed to stand for separation, the aqueous phase was extracted with ethyl acetate twice, the organic phases were combined, washed with water three times, rotary evaporated, and column chromatography was performed using a mixture of petroleum ether and dichloromethane as the eluent to give Intermediate 2 (12.82 g, HPLC showed a purity of 99.0%).

[0070] P3. Under nitrogen protection, intermediate 2 (12.82 g, 1.0 eq) and raw material 3 (14.03 g, 2.2 eq) were dissolved in a toluene solution (120 g), sodium tert-butoxide (11.50 g, 4.0 eq) was added, tris(dibenzylideneacetone)dipalladium (0.5 g, 0.02 eq), tri-tert-butylphosphine (0.7 g, 0.12 eq) were stirred uniformly, the temperature was raised to 120 °C, and the reaction was refluxed for 12 h; after the reaction was completed, the temperature was slightly lowered, diatomite was used for filtration to remove the salt and catalyst, the filtrate was cooled to room temperature, washed with water three times, the organic phase was reserved, then the water phase was extracted with ethyl acetate; after the organic phases were combined, anhydrous magnesium sulfate was used for drying, and a rotary evaporator was used to remove the solvent; recrystallization was performed in petroleum ether / ethanol, filtration was performed, the filter cake was washed with petroleum ether for multiple times, and was placed in a 60 °C oven for drying for 7 h to obtain the reinforcing material 1 (15.45 g, HPLC showed a purity of 99.9%). Compound characterization data MS (MS+H + ): 693.

[0071] Compound characterization data 1 H NMR (deuterated chloroform) δ 8.84 (s, 4H), 7.29 (d, 2H), 7.27 (d, 2H), 7.21 (d, 2H), 7.20 (d, 2H), 1.41 (s, 18H), 1.34 (s, 18H).

[0072] Example 1-2

[0073] Synthesis of reinforcing material 3: referring to the forming process of the reinforcing material 1 in Example 1-1, raw material 3 therein was replaced by: (CAS registration number: 243664-79-1), and the rest of the feed, equivalent and post-treatment were the same as in Example 1-1.

[0074] Further, the structure of the reinforcing material 3 is: Compound characterization data MS (MS+H + ): 793.

[0075] Example 1-3

[0076] Synthesis of reinforcing material 6: referring to the forming process of the reinforcing material 1 in Example 1-1, raw material 3 therein was replaced by: (CAS registration number: 162258-89-1), and the rest of the feed, equivalent and post-treatment were the same as in Example 1-1.

[0077] Further, the structure of the reinforcing material 6 is: Compound characterization data MS (MS+H + ): 845.

[0078] Example 1-4

[0079] Synthesis of the reinforcing material 8: referring to the forming process of the reinforcing material 1 in Example 1-1, the raw material 2 therein is replaced by: (CAS Registry No.: 42310-83-8), and the rest of the feedstock, equivalent and post-treatment are the same as Example 1-1.

[0080] Further, the structure of the reinforcing material 8 is: Compound characterization data MS (MS+H + ): 711.

[0081] Example 1-5

[0082] Synthesis of the reinforcing material 9: referring to the forming process of the reinforcing material 1 in Example 1-1, the raw material 3 therein is replaced by: (CAS Registry No.: 2415104-41-3), and the rest of the feedstock, equivalent and post-treatment are the same as Example 1-1.

[0083] Further, the structure of the reinforcing material 9 is: Compound characterization data MS (MS+H + ): 855.

[0084] Example 1-6

[0085] Synthesis of the reinforcing material 10: referring to the forming process of the reinforcing material 1 in Example 1-1, the raw material 3 therein is replaced by: (CAS Registry No.: 875796-41-1), and the rest of the feedstock, equivalent and post-treatment are the same as Example 1-1.

[0086] Further, the structure of the reinforcing material 10 is: Compound characterization data MS (MS+H + ): 813.

[0087] Example 1

[0088] The composition of a high-strength ceramic is: reinforcing material (prepared in Example 1-1): 8 parts, kaolin: 42 parts, quartz sand: 35 parts, alumina: 12 parts, nano-silica (toughening agent): 5 parts, zirconia (pigment): 2 parts

[0089] The forming process of a high-strength ceramic is:

[0090] S1. Pre-dispersion treatment: the reinforcing material is pre-mixed with tetrahydrofuran at a mass ratio of 1:3 at 50°C to form a reinforcing material mother liquor;

[0091] S2. Gradient mixing: the reinforcing material mother liquor is added to the dry powder of kaolin, quartz sand, and alumina three times with ultrasonic dispersion, mixing and dispersion, and ultrasonic auxiliary dispersion at a frequency of 40 kHz and a power density of 0.5 W / cm 3 , the mixing temperature is controlled at 50°C, and the mixture is worth mixing;

[0092] S3. High-pressure homogenization: the mixture is stirred and homogenized at a pressure of 60 MPa, so that the particle size D 50 ≤2 μm;

[0093] S4. Solidification: solidification at 80°C for 5 hours, heating to 800°C at a rate of 10°C / min, holding for 1 hour, then heating to 1250°C at a rate of 10°C / min, sintering for 2 hours, and then quenching treatment, cooling the ceramic from 1250°C to 600°C at a rate of ≥50°C / min.

[0094] Example 2

[0095] In this example, a high-strength ceramic is prepared by referring to the composition and molding process in Example 1, replacing the reinforcing material 1 therein with reinforcing material 3 (prepared in Example 1-1), and the rest of the composition and molding process is the same as Example 1.

[0096] Example 3

[0097] In this example, a high-strength ceramic is prepared by referring to the composition and molding process in Example 1, replacing the reinforcing material 1 therein with reinforcing material 6 (prepared in Example 1-3), and the rest of the composition and molding process is the same as Example 1.

[0098] Example 4

[0099] In this example, a high-strength ceramic is prepared by referring to the composition and molding process in Example 1, replacing the reinforcing material 1 therein with reinforcing material 8 (prepared in Example 1-4), and the rest of the composition and molding process is the same as Example 1.

[0100] Example 5

[0101] In this example, a high-strength ceramic is prepared by referring to the composition and molding process in Example 1, replacing the reinforcing material 1 therein with reinforcing material 9 (prepared in Example 1-5), and the rest of the composition and molding process is the same as Example 1.

[0102] Example 6

[0103] In this example, a high-strength ceramic is prepared by referring to the composition and molding process in Example 1, replacing the reinforcing material 1 therein with reinforcing material 10 (prepared in Example 1-6), and the rest of the composition and molding process is the same as Example 1.

[0104] Comparative Example 1

[0105] A ceramic was prepared according to the composition and forming process of Example 1, with the exception that the reinforcing material 1 was replaced with Comparative Reinforcing Material 1. The remaining composition and forming process was the same as Example 1.

[0106] The structure of Comparative Reinforcing Material 1 (CAS Registry Number: 136715-11-2) is:

[0107] Comparative Example 2

[0108] A ceramic was prepared according to the composition and forming process of Example 1, with the exception that the reinforcing material 1 was replaced with Comparative Reinforcing Material 2. The remaining composition and forming process was the same as Example 1.

[0109] The structure of Comparative Reinforcing Material 2 (CAS Registry Number: 1222513-27-0) is:

[0110] Comparative Example 3

[0111] A ceramic was prepared according to the composition and forming process of Example 1, with the exception that the reinforcing material was not added. The remaining composition and forming process was the same as Example 1.

[0112] Comparative Example 4

[0113] A ceramic was prepared according to the composition and forming process of Example 1, with the exception that the kaolin was added to 50 parts (5 parts over the upper limit). The remaining composition and forming process was the same as Example 1.

[0114] Comparative Example 5

[0115] A ceramic was prepared according to the composition and forming process of Example 1, with the exception that the toughening agent was replaced with micron-sized calcium carbonate. The remaining composition and forming process was the same as Example 1.

[0116] Comparative Example 6

[0117] A ceramic was prepared according to the composition and forming process of Example 1, with the exception that the quenching step was not performed and was naturally cooled to room temperature. The remaining composition and forming process was the same as Example 1.

[0118] Performance Test:

[0119] Twelve ceramics obtained from Examples 1-6 and Comparative Examples 1-6 were cut into 2.2mm x 2.2mm x 25mm samples (n = 15) using a diamond dicing saw. The samples were sanded with 1000#, 1500# and 2000# sandpaper, and then polished with 0.5pm diamond suspension to obtain samples with dimensions of (2±0.1)mm x (2±0.1)mm x 25mm, which were used for flexural strength testing. Samples with dimensions of 2mm x 4mm x 4mm were prepared using the same sample preparation method and were used for nanoindentation testing.

[0120] Flexural strength testing was performed using a universal testing machine according to the three-point bending method (standard EN ISO-4049) at a constant loading speed of 0.75mm / min. Hardness and elastic modulus testing was performed using a nanoindenter (MTS, G200, America) and 10 points were randomly selected for each material. The testing depth was fixed at 2000nm and the results of the performance tests are shown in Table 1.

[0121] Table 1. Main parameters and performance test results of the ceramic composite materials obtained in the examples and comparative examples.

[0122]

[0123] The comparative analysis of the examples and comparative examples verifies the significant improvement in key performance indicators such as flexural strength, elastic modulus, and Vickers hardness. The flexural strength of Example 4 is 189.8MPa, which is 57MPa higher than that of Comparative Example 3 without reinforcing materials. This is mainly due to the isotopic effect of deuterated methyl groups and the interface reinforcing effect of anthracene-based aromatic ring structures, as well as the rapid cooling process which improves surface density and reduces microcracks. In terms of elastic modulus, Example 4 achieves an optimization effect of 39.8GPa through nano-silica toughening agent and high-pressure homogenization process, which is 16.3GPa higher than that of Comparative Example 5 with micron-sized calcium carbonate. In terms of Vickers hardness, Examples 4 and 5 form sub-micron whiskers and chemical bonding through the rapid cooling process, with a hardness of 4.7GPa, which is 1.2GPa higher than that of Comparative Example 6 which is naturally cooled. The imbalance verification shows that an excess of kaolin will result in a decrease in performance and damage to the wrapping rate of the reinforcing materials and thermal shock stability.

[0124] Although embodiments of the present application have been shown and described, it is to be understood that various modifications, substitutions, replacements and changes can be made to these embodiments without departing from the principles and spirit of the present application, and the scope of the present application is defined by the appended claims and their equivalents.

Claims

1. A high-strength ceramic forming process, characterized in that: The following steps are involved: S1. Pre-dispersion treatment: pre-mixing the reinforcing material with an organic solvent to form a reinforcing material mother liquid; S2 gradient mixing: The reinforcing material mother solution was added three times to kaolin, quartz sand, alumina powder, mixed and dispersed, the mixing temperature was controlled at 40-50 ℃, to obtain a mixture; S3. High pressure homogenization: Stir and homogenize the mixture under a pressure of 60-80 MPa to make the particle size D 50 ≤2μm; S4 curing: curing at 60-80 ℃ stage for 3-5 hours, heating to 600-800 ℃ at 5-10 ℃ / min for 1 hour, then heating to 1250-1300 ℃ at 5-10 ℃ / min and sintering for 2 hours; After the S4 is heated to 1250-1300°C and sintered for 2 hours, a rapid cooling treatment is added: the ceramic is cooled from 1250°C to 600°C at a rate of ≥50°C / min to improve the surface density; The high-strength ceramic comprises the following components in a weight ratio: 3-10 parts of reinforcing material, 40-45 parts of kaolin, 25-40 parts of quartz sand, 8-15 parts of alumina, 3-7 parts of toughening agent, and 1-3 parts of pigment. The reinforcing material is selected from any one compound of reinforcing material 1 to reinforcing material 16: The toughening agent is selected from: nano silicon dioxide; Each time the reinforcing material mother solution is added to S2 for mixing and dispersion, ultrasonic wave is simultaneously applied to assist dispersion, with a frequency of 30-40 kHz and a power density of 0.5 W / cm 3 .

2. A high-strength ceramic forming process according to claim 1, characterized in that: The pigment is selected from one or more of zirconium oxide, silicon nitride and silicon carbide.

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