A porcelain clay composition, ceramic and applications

Abstract

This invention discloses a ceramic clay composition, ceramics, and their applications, relating to the field of ceramic technology. The ceramics of this invention are obtained by sequentially processing the ceramic clay composition through a process of material conditioning, sieving, casting, air drying, oven drying, and sintering. The introduction of specific proportions of ceramic waste A and B, modified particles with a gallium-coated cuprous oxide core and an alumina shell, and high-entropy oxide solid solutions generated from the reaction of hafnium dioxide, tantalum pentoxide, niobium pentoxide, titanium dioxide, zirconium dioxide, chromium trioxide, and carbon powder, as well as chromium heptacarbonide, into the ceramic clay composition gives the ceramics prepared from the ceramic waste excellent fracture toughness, flexural strength, wear resistance, high-temperature resistance, and self-healing ability. Therefore, this invention has broad application prospects.

Description

Technical Field

[0001] This invention relates to the field of ceramic technology, specifically to a porcelain clay composition, ceramics, and their applications. Background Technology

[0002] Ceramics are a class of solid materials made primarily of inorganic non-metallic materials through processes such as raw material preparation, molding, and high-temperature sintering. They possess unique properties such as high hardness, corrosion resistance, and good insulation, and are widely used in everyday life, including tableware, teaware, vases, tiles, and sanitary ware, as well as in the machinery, electronics, chemical, medical, aerospace, and defense industries. However, this process also generates a large amount of ceramic waste. Currently, the main methods for disposing of ceramic waste are open-air dumping and landfilling, which not only consumes significant resources but also easily leads to air and groundwater pollution.

[0003] Furthermore, existing ceramics still suffer from poor toughness and brittleness in practical applications, as well as relatively poor high-temperature resistance, with strength, hardness, and toughness significantly decreasing at high temperatures, thus limiting their applications. Therefore, reasonable recycling methods for ceramic waste are still needed, and the high-temperature resistance and toughness of existing ceramic materials still require further improvement. Summary of the Invention

[0004] The purpose of this invention is to provide a porcelain clay composition, ceramics, and their applications, thereby solving the following technical problems:

[0005] Existing ceramic materials still suffer from poor toughness and high-temperature resistance.

[0006] The objective of this invention can be achieved through the following technical solutions:

[0007] A porcelain clay composition comprising the following raw materials in parts by weight: ceramic waste A 20-24 parts, ceramic waste B 20-24 parts, potassium-sodium feldspar 15-18 parts, clay 5-6 parts, hafnium dioxide 8.05-9.66 parts, tantalum pentoxide 8.45-10.14 parts, niobium pentoxide 5.08-6.1 parts, titanium dioxide 1.53-1.84 parts, zirconium dioxide 4.71-5.65 parts, chromium trioxide 12.10-14.52 parts, carbon powder 3.5-4.2 parts, modified particles 3.5-5.5 parts, and deionized water 8-12 parts;

[0008] The modified particles are composite particles with gallium-coated cuprous oxide as the core and aluminum oxide as the shell.

[0009] Preferably, the method for preparing the porcelain clay composition is as follows:

[0010] Ceramic waste A, ceramic waste B, potassium and sodium feldspar, and clay are mixed, crushed, and ball-milled. After passing through a 150-200 mesh sieve, the mixture is then mixed with hafnium dioxide, tantalum pentoxide, niobium pentoxide, titanium dioxide, zirconium dioxide, chromium trioxide, carbon powder, modified particles, and anhydrous ethanol. The mixture is then ultrasonically treated for 30-50 minutes. Subsequently, using zirconium oxide balls as the medium, the mixture is ball-milled at 180-220 r / min for 24-30 hours. The anhydrous ethanol is then removed by rotary evaporation. Finally, deionized water is added and the mixture is stirred for 20-40 minutes to obtain the porcelain clay composition.

[0011] Preferably, the modified particles are prepared by the following method:

[0012] A1: Dissolve copper sulfate pentahydrate in deionized water and adjust the pH to 9.0-9.5 with 0.1 mol / L sodium hydroxide aqueous solution. Then add ascorbic acid aqueous solution and polyvinylpyrrolidone ethanol solution dropwise and stir at 45-50℃ for 30-50 min. Centrifuge and wash the precipitate 3-5 times with anhydrous ethanol. Then vacuum dry at 55-60℃ to obtain cuprous oxide nanospheres.

[0013] A2: Liquid gallium metal is liquefied by heating to 45-50℃ in an argon atmosphere, then cuprous oxide nanospheres and oleic acid are added and ultrasonically broken up for 45-55 minutes at a power of 300-350W and a frequency of 20-25kHz to obtain coated microdroplets.

[0014] A3: Add oleylamine and aluminum isopropoxide to the reactor and heat to 175-180℃ under a nitrogen atmosphere. Then add coated microdroplets and stir at 180-220 r / min for 2-2.5 h at 175-180℃. After cooling, centrifuge and separate the particles. Then wash with cyclohexane 3 times, anhydrous ethanol 2 times, and cyclohexane 1-2 times in sequence. Select 200-500 nm particles by air-gas fractionation. Finally, heat the mixture to 350-360℃ at 3-5℃ / min under an argon atmosphere and hold for 2-2.5 h. After cooling, obtain the modified particles.

[0015] Preferably, the mass ratio of copper sulfate pentahydrate, deionized water, ascorbic acid aqueous solution, and polyvinylpyrrolidone ethanol solution in A1 is 25-30:300-360:100-120:8-9.5;

[0016] The concentration of the ascorbic acid aqueous solution described in A1 is 1 mol / L;

[0017] The concentration of the polyvinylpyrrolidone ethanol solution described in A1 is 0.1 mol / L.

[0018] Preferably, the mass ratio of liquid gallium, cuprous oxide nanospheres, and oleic acid in A2 is 50-60:5-6:0.5-0.6.

[0019] Preferably, the mass ratio of oleylamine, aluminum isopropoxide, and coated microdroplets in A3 is 123-148:20.4-24.5:55-66.

[0020] A type of ceramic, prepared by the following method:

[0021] S1: After the porcelain clay composition is left to stand for 12-18 hours, it is passed through a 50-60 mesh sieve, then poured into a mold and subjected to pressure treatment. After molding, it is dried and then dried at 105-110℃ to obtain a green body.

[0022] S2: The green body is placed between graphite felts and sintered to obtain ceramics.

[0023] Preferably, the pressure during the pressure holding process in S1 is 28-30 MPa, and the pressure holding time is 30-40 s.

[0024] Preferably, the sintering process described in S2 is as follows: first, apply 150-200A AC current under an argon atmosphere and heat to 1850-1900℃ within 20-25s, hold at that temperature for 60-70s, then cool to 650-670℃ under an argon atmosphere, then heat to 1050-1100℃ at 5-10℃ / min under an argon atmosphere and hold for 3-4h, then cool to 650-700℃ at 3-5℃ / min under an argon atmosphere and hold for 30-50min, and finally cool with the furnace.

[0025] An application of a ceramic, said ceramic being used in the fields of mechanical bearings, cutting tools, building pipes, and building ceramic tiles.

[0026] The beneficial effects of this invention are:

[0027] This invention provides a ceramic clay composition, ceramics, and applications. The invention effectively improves the high-temperature resistance and toughness of ceramic materials through the following methods.

[0028] (1) The modified particles of this invention are uniformly dispersed in the ceramic matrix. When the crack extends to the vicinity of the particles, it will be deflected or "bridged" by the particles due to the difference in the interfacial bonding force between the particles and the matrix, thus consuming more fracture energy. Liquid gallium metal can undergo plastic deformation under stress, absorbing the stress concentration at the crack tip and alleviating the tendency of brittle fracture. Cuprous oxide may undergo local phase transformation under high temperature sintering or stress, accompanied by volume expansion, which can offset the tensile stress at the crack tip and inhibit crack propagation. The modified particles, as the second phase, are uniformly distributed in the matrix, which can refine the matrix grains and significantly improve the bending strength. After the particle surface is modified with oleic acid and oleylamine, the interfacial compatibility with the ceramic matrix is ​​improved, which can reduce interfacial porosity and stress concentration, so that the load can be transmitted more evenly and avoid early fracture caused by interfacial debonding. The nanoparticles can fill the micropores in the matrix, improve the ceramic density, and improve the bending strength. Cuprous oxide can improve surface microhardness and reduce material spalling during wear. Gallium in the particles may soften and leach due to frictional heat during friction, forming a metallic lubricating film at the wear interface, reducing adhesive wear and abrasive wear. Increased density makes the material surface smoother, reducing the possibility of abrasive grain embedding and further reducing the wear rate. Cuprous oxide, aluminum-based oxide, and high-melting-point phases in the matrix form a high-temperature resistant framework, which can maintain the structural stability after sintering and inhibit grain coarsening and grain boundary softening at high temperatures. At high temperatures, gallium may melt and fill microcracks or pores inside the ceramic, reducing the channels for gas permeation and oxidation corrosion at high temperatures, especially protecting the carbide phase from oxidation in an argon atmosphere. The difference in thermal expansion coefficient between the nanoparticles and the matrix oxide is small, which can reduce thermal stress during high-temperature cycling and improve thermal shock resistance. When microcracks form in ceramics, gallium in the particles can melt and penetrate along the cracks under high temperature or external force. After cooling, it solidifies to form a metal "rivet" that fills the cracks and restores some mechanical properties. Cuprous oxide in an oxygen-containing environment can react with carbon or oxides at the cracks to fill the crack gaps and enhance the bonding force at the crack interface.

[0029] (2) Cordierite in ceramic waste A of this invention has a low elastic modulus and a low coefficient of thermal expansion, which can alleviate stress concentration at the crack tip; mullite in ceramic waste B can consume crack propagation energy through the "crack bridging" and "crack deflection" mechanisms; quartz, which is present in both wastes, is a rigid phase and can form a multiphase interface with cordierite and mullite. When the crack propagates, it needs to bypass different phase interfaces, increasing energy consumption; under a specific ratio, the low stress characteristics of cordierite combined with the toughening morphology of mullite can reduce the brittle defects of a single phase, thereby improving fracture toughness. The mullite crystal network can strengthen the matrix skeleton, cordierite can reduce the thermal stress during sintering and reduce microcracks caused by thermal expansion mismatch, and quartz can react with other components to generate a low-melting-point glass phase, reducing porosity and thus improving the bending strength of the material. Mullite and quartz can directly resist the cutting and ploughing effects of external abrasive particles, while cordierite can reduce the brittle spalling of the high-hardness phase during wear. The high density achieved through sintering of these two waste materials enhances wear resistance. Mullite ensures high-temperature structural stability, cordierite improves thermal shock resistance, and quartz can be converted into a stable phase through reaction, enhancing the material's resistance to cracking and softening at high temperatures. When microcracks develop in the material, the glassy phase can flow and fill the cracks at high temperatures, and solidify upon cooling to achieve healing. Cordierite can reduce thermal stress during crack healing, preventing secondary cracking. The high-temperature stability of mullite provides structural support for crack healing and can synergistically promote healing with modified particles.

[0030] (3) When the zirconium dioxide of the present invention is sintered or subjected to stress, it will undergo a martensitic phase transformation from tetragonal to monoclinic phase. The volume expansion can compress the crack tip and consume the crack propagation energy. High hardness particles such as hafnium dioxide are uniformly dispersed in the matrix. When the crack propagation encounters these particles, the path will be deflected or branched, increasing the crack propagation path length and consuming more energy. Carbon powder and chromium trioxide react at high temperature to generate chromium heptacarbide, which is pinned to the crack tip and hinders the further propagation of the crack, especially forming a "mechanical anchor" at the interface between the ceramic matrix and the particles. Hafnium dioxide, tantalum pentoxide, niobium pentoxide, titanium dioxide, and zirconium dioxide can form high-entropy oxide solid solutions during high-temperature sintering, which enhance the flexural strength of the matrix through lattice distortion. Nanoscale chromium heptacarbide and hafnium dioxide particles are dispersed in the matrix, effectively transferring loads and reducing stress concentration. These oxides have good compatibility with ceramic waste and can fill matrix pores at high temperatures, increasing density and reducing strength degradation caused by porosity. The presence of high-hardness phases such as hafnium dioxide increases the microhardness of the ceramic surface, resisting abrasive cutting during wear. Ball milling ensures uniform distribution of high-hardness particles, forming a "wear-resistant skeleton," maintaining long-term wear resistance even after surface wear due to continuous exposure of high-hardness phases. Chromium trioxide can form a dense chromium trioxide oxide film at high temperatures, preventing further oxidation of silicon, aluminum, and other elements in the matrix and avoiding strength reduction due to oxidation at high temperatures. The thermal expansion coefficient of the high-entropy oxide solid solution is close to that of the ceramic waste matrix, reducing cracking caused by high-temperature thermal stress. At high temperatures, chromium trioxide can migrate to microcracks and react with the surrounding silica to form a low-melting-point silicate glass phase, filling the micron-sized cracks. Carbon powder can diffuse to the crack tip at high temperatures and react with chromium trioxide again to form chromium heptacarbide, repairing the mechanical defects at the crack.

[0031] Therefore, the ceramics prepared by the present invention using ceramic waste and other components have excellent toughness, high temperature resistance, and self-healing ability, as well as a wider range of application prospects. Detailed Implementation

[0032] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0033] Unless otherwise specified, the following information pertains to some of the raw materials used in the following embodiments and comparative examples of this invention:

[0034] The main phases of ceramic waste A are quartz (SiO2) and cordierite (Mg2Al4Si5O). 18The ceramic waste B was purchased from Fujian Desheng New Building Materials Co., Ltd.; the main phases of the ceramic waste B are quartz phase (SiO2) and mullite phase (Al6Si2O). 13 Purchased from Fujian Desheng New Building Materials Co., Ltd.; Polyvinylpyrrolidone purchased from Shanghai Yuanye Biotechnology Co., Ltd., item number: S30268.

[0035] Example 1: A porcelain clay composition and a method for preparing ceramics are as follows:

[0036] S1: Dissolve 25g of copper sulfate pentahydrate in 300mL of deionized water and adjust the pH to 9.0 with 0.1mol / L sodium hydroxide aqueous solution. Then add 100g of 1mol / L ascorbic acid aqueous solution and 8g of 0.1mol / L polyvinylpyrrolidone ethanol solution. Stir at 45℃ for 50min. Centrifuge and wash the precipitate three times with anhydrous ethanol. Then vacuum dry at 55℃ to obtain cuprous oxide nanospheres.

[0037] S2: 50g of liquid gallium metal was heated to 45℃ in an argon atmosphere to liquefy it. Then, 5g of cuprous oxide nanospheres and 0.5g of oleic acid were added and ultrasonically broken up for 45min at a power of 350W and a frequency of 25kHz to obtain coated microdroplets.

[0038] S3: Add 123g of oleylamine and 20.4g of aluminum isopropoxide to the reactor and heat to 175℃ under a nitrogen atmosphere. Then inject 55g of coated microdroplets and stir at 180r / min for 2.5h at 175℃. After cooling, centrifuge and separate the particles. Then wash with cyclohexane 3 times, anhydrous ethanol 2 times, and cyclohexane 1 time in sequence. Select particles with a particle size of 200-500nm by air flow classification. Finally, heat to 350℃ at 3℃ / min under an argon atmosphere and hold for 2h. After cooling, obtain modified particles.

[0039] S4: Mix and crush 20g of ceramic waste A, 20g of ceramic waste B, 15g of potassium sodium feldspar, and 5g of clay, then ball mill them. After passing through a 150-mesh sieve, mix them with 8.05g of hafnium dioxide, 8.45g of tantalum pentoxide, 5.08g of niobium pentoxide, 1.53g of titanium dioxide, 4.71g of zirconium dioxide, 12.10g of chromium trioxide, 3.5g of carbon powder, 3.5g of modified particles, and 155g of anhydrous ethanol. Then, ultrasonically treat the mixture for 30 minutes. After that, ball mill the mixture at 180r / min for 30 hours using 350g of zirconium oxide balls as the medium. Then, remove the anhydrous ethanol by rotary evaporation. Finally, add 8g of deionized water and stir for 20 minutes to obtain the porcelain clay composition.

[0040] S5: After the porcelain clay composition is left to stand for 12 hours, it is passed through a 50-mesh sieve, then poured into a mold and held under pressure at 28MPa for 40 seconds. After molding, it is dried for 24 hours and then baked at 105℃ for 30 hours to obtain the green body.

[0041] S6: The green body is placed between graphite felts, and a 150A AC current is applied under an argon atmosphere to raise the temperature to 1850℃ within 20s. After holding at this temperature for 60s, it is cooled to 650℃ under an argon atmosphere. Then, the temperature is raised to 1050℃ at a rate of 5℃ / min under an argon atmosphere and held for 4h. After that, it is cooled to 650℃ at a rate of 3℃ / min under an argon atmosphere and held for 30min. The ceramic is obtained after cooling in the furnace.

[0042] Example 2: A porcelain clay composition and a method for preparing ceramics are as follows:

[0043] S1: Dissolve 27.5g of copper sulfate pentahydrate in 330mL of deionized water and adjust the pH to 9.3 with 0.1mol / L sodium hydroxide aqueous solution. Then add 110g of 1mol / L ascorbic acid aqueous solution and 8.7g of 0.1mol / L polyvinylpyrrolidone ethanol solution. Stir at 48℃ for 40min. Centrifuge and wash the precipitate 4 times with anhydrous ethanol. Then vacuum dry at 58℃ to obtain cuprous oxide nanospheres.

[0044] S2: 55g of liquid gallium metal was heated to 48℃ in an argon atmosphere to liquefy it. Then, 5.5g of cuprous oxide nanospheres and 0.55g of oleic acid were added and ultrasonically broken up for 50min at a power of 330W and a frequency of 23kHz to obtain coated microdroplets.

[0045] S3: Add 135g of oleylamine and 22.4g of aluminum isopropoxide to the reactor and heat to 178℃ under a nitrogen atmosphere. Then, slowly inject 60g of coated microdroplets and stir at 200r / min for 2.3h at 178℃. After cooling, centrifuge and separate the particles. Then wash with cyclohexane 3 times, anhydrous ethanol 2 times, and cyclohexane 2 times in sequence. Select particles with a particle size of 200-500nm by air flow classification. Finally, heat the mixture to 355℃ at 4℃ / min under an argon atmosphere and hold for 2.2h. After cooling, obtain the modified particles.

[0046] S4: Mix and crush 22g of ceramic waste A, 22g of ceramic waste B, 16.5g of potassium sodium feldspar, and 5.5g of clay, then ball mill them. After passing through a 180-mesh sieve, mix them with 8.85g of hafnium dioxide, 9.3g of tantalum pentoxide, 5.6g of niobium pentoxide, 1.68g of titanium dioxide, 5.18g of zirconium dioxide, 13.31g of chromium trioxide, 3.85g of carbon powder, 4.5g of modified particles, and 170.5g of anhydrous ethanol. Sonicate for 40 minutes. Then, ball mill at 200r / min for 27 hours using 400g of zirconium oxide balls as the medium. Remove the anhydrous ethanol by rotary evaporation. Finally, add 10g of deionized water and stir for 30 minutes to obtain the porcelain clay composition.

[0047] S5: After the porcelain clay composition is left to stand for 15 hours, it is passed through a 55-mesh sieve, then injected into a mold and held under pressure at 29MPa for 35 seconds. After molding, it is dried for 27 hours and then baked at 108℃ for 27 hours to obtain the green body.

[0048] S6: The green body is placed between graphite felts, and a 180A AC current is applied under an argon atmosphere to raise the temperature to 1880℃ within 23s. After holding at this temperature for 65s, it is cooled to 660℃ under an argon atmosphere. Then, it is raised to 1080℃ at a rate of 8℃ / min under an argon atmosphere and held for 3.5h. After that, it is cooled to 680℃ at a rate of 4℃ / min under an argon atmosphere and held for 40min. After cooling in the furnace, the ceramic is obtained.

[0049] Example 3: A porcelain clay composition and a method for preparing ceramics are as follows:

[0050] S1: Dissolve 30g of copper sulfate pentahydrate in 360mL of deionized water and adjust the pH to 9.5 with 0.1mol / L sodium hydroxide aqueous solution. Then add 120g of 1mol / L ascorbic acid aqueous solution and 9.5g of 0.1mol / L polyvinylpyrrolidone ethanol solution. Stir at 50℃ for 30min. Centrifuge and wash the precipitate 5 times with anhydrous ethanol. Then vacuum dry at 60℃ to obtain cuprous oxide nanospheres.

[0051] S2: 60g of liquid gallium metal was heated to 50℃ in an argon atmosphere to liquefy it. Then, 6g of cuprous oxide nanospheres and 0.6g of oleic acid were added and ultrasonically broken up for 55min at a power of 300W and a frequency of 20kHz to obtain coated microdroplets.

[0052] S3: Add 148g of oleylamine and 24.5g of aluminum isopropoxide to the reactor and heat to 180℃ under a nitrogen atmosphere. Then slowly inject 66g of coated microdroplets and stir at 220r / min for 2h at 180℃. After cooling, centrifuge and separate the particles. Then wash with cyclohexane 3 times, anhydrous ethanol 2 times, and cyclohexane 2 times in sequence. Select particles with a particle size of 200-500nm by air flow classification. Finally, heat to 360℃ at 5℃ / min under an argon atmosphere and hold for 2h. After cooling, obtain modified particles.

[0053] S4: Mix and crush 24g of ceramic waste A, 24g of ceramic waste B, 18g of potassium sodium feldspar, and 6g of clay, then ball mill them. After passing through a 200-mesh sieve, mix them with 9.66g of hafnium dioxide, 10.14g of tantalum pentoxide, 6.1g of niobium pentoxide, 1.84g of titanium dioxide, 5.65g of zirconium dioxide, 14.52g of chromium trioxide, 4.2g of carbon powder, 5.5g of modified particles, and 186g of anhydrous ethanol. Sonicate for 50 minutes. Then, ball mill at 220r / min for 24 hours using 450g of zirconium oxide balls as the medium. Remove the anhydrous ethanol by rotary evaporation. Finally, add 12g of deionized water and stir for 40 minutes to obtain the porcelain clay composition.

[0054] S5: After the porcelain clay composition is left to stand for 18 hours, it is passed through a 60-mesh sieve, then poured into a mold and held under pressure at 30MPa for 30 seconds. After molding, it is dried for 30 hours and then baked at 110℃ for 24 hours to obtain the green body.

[0055] S6: Place the green body between graphite felts, apply 200A AC current under argon atmosphere and heat to 1900℃ within 20s, hold for 70s and then cool to 670℃ under argon atmosphere. Then heat to 1100℃ at 10℃ / min under argon atmosphere and hold for 3h. Then cool to 700℃ at 5℃ / min under argon atmosphere and hold for 50min. After cooling in the furnace, the ceramic is obtained.

[0056] Comparative Example 1:

[0057] Compared with Example 1, this comparative example only replaces "ceramic waste A" added in the preparation process of S4 with "ceramic waste B". All other steps and parameters are the same, and will not be repeated in this comparative example. Finally, ceramics are obtained.

[0058] Comparative Example 2:

[0059] Compared with Example 1, this comparative example only replaces "ceramic waste B" added in the preparation process of S4 with "ceramic waste A". All other steps and parameters are the same, and will not be repeated in this comparative example. Finally, ceramics are obtained.

[0060] Comparative Example 3:

[0061] Compared with Example 1, this comparative example only omits the addition of "hafnium dioxide, tantalum pentoxide, niobium pentoxide, titanium dioxide, and zirconium dioxide" during the preparation process of S4. All other steps and parameters are the same, and will not be repeated here. The final product is ceramic.

[0062] Comparative Example 4:

[0063] Compared with Example 1, this comparative example only did not add "chromium trioxide" in the preparation process of S4. All other steps and parameters were the same, and will not be repeated here. The final product was ceramic.

[0064] Comparative Example 5:

[0065] Compared with Example 1, this comparative example only replaces the "modified particles" added in the preparation process of S4 with the "cuprous oxide nanospheres" prepared in S1. All other steps and parameters are the same, and will not be repeated in this comparative example. Finally, ceramics are obtained.

[0066] Comparative Example 6:

[0067] Compared with Example 1, this comparative example only did not add "modified particles" in the preparation process of S4. All other steps and parameters were the same, and will not be repeated here. The final product was ceramic.

[0068] Performance testing:

[0069] Determination of fracture toughness:

[0070] Referring to GB / T 23806-2009 "Test Method for Fracture Toughness of Fine Ceramics - Single-Sided Pre-Cracked Beam Method", the fracture toughness (MPa·m) of the ceramics prepared in Examples 1-3 and Comparative Examples 1-6 of this invention was determined. 1 / 2 The test results are shown in Table 1.

[0071] Determination of flexural strength and abrasion resistance:

[0072] Referring to GB / T 3810-2016 "Test Methods for Ceramic Tiles", the flexural strength (MPa) and abrasion resistance (mg) of the ceramics prepared in Examples 1-3 and Comparative Examples 1-6 of this invention were determined, and the test results are shown in Table 1.

[0073] Determination of high temperature resistance:

[0074] Referring to GB / T 14390-2008 "Test Method for High Temperature Bending Strength of Fine Ceramics", the flexural strength retention rate (%) of the ceramics prepared in Examples 1-3 and Comparative Examples 1-6 of this invention at 1300℃ was determined, and the test results are shown in Table 1.

[0075] Determination of self-repair capability:

[0076] Referring to GB / T 23806-2009 "Test Method for Fracture Toughness of Fine Ceramics - Single-Sided Pre-cracked Beam Method", the flexural strength retention rate (%) of the ceramics prepared in Examples 1-3 and Comparative Examples 1-6 of this invention after being placed at 25°C and 60% relative humidity for 48 hours after three-point bending pre-crack treatment was determined. The test results are shown in Table 1.

[0077] Table 1: Performance test results of Examples 1-3 and Comparative Examples 1-6

[0078]

[0079] Data Analysis:

[0080] As can be seen from Table 1, the ceramics prepared in the embodiments of the present invention have excellent fracture toughness, bending strength, wear resistance, high temperature resistance and self-healing ability.

[0081] The foregoing has provided a detailed description of one embodiment of the present invention, but this description is merely a preferred embodiment and should not be construed as limiting the scope of the invention. All equivalent variations and modifications made within the scope of the claims of this invention should still fall within the patent coverage of this invention.

Claims

1. A porcelain clay composition, characterized in that, The raw materials include the following parts by weight: ceramic waste A 20-24 parts, ceramic waste B 20-24 parts, potassium sodium feldspar 15-18 parts, clay 5-6 parts, hafnium dioxide 8.05-9.66 parts, tantalum pentoxide 8.45-10.14 parts, niobium pentoxide 5.08-6.1 parts, titanium dioxide 1.53-1.84 parts, zirconium dioxide 4.71-5.65 parts, chromium trioxide 12.10-14.52 parts, carbon powder 3.5-4.2 parts, modified granules 3.5-5.5 parts, and deionized water 8-12 parts; The modified particles are composite particles with gallium-coated cuprous oxide as the core and aluminum oxide as the shell.

2. The porcelain clay composition according to claim 1, characterized in that, The method for preparing the porcelain clay composition is as follows: Ceramic waste A, ceramic waste B, potassium and sodium feldspar, and clay are mixed, crushed, and ball-milled. After passing through a 150-200 mesh sieve, they are mixed with hafnium dioxide, tantalum pentoxide, niobium pentoxide, titanium dioxide, zirconium dioxide, chromium trioxide, carbon powder, modified particles, and anhydrous ethanol, and ultrasonicated for 30-50 minutes. Then, they are ball-milled with zirconium oxide balls as the medium for 24-30 hours. The anhydrous ethanol is then removed by rotary evaporation. Finally, deionized water is added and stirred to obtain a porcelain clay composition.

3. The porcelain clay composition according to claim 1, characterized in that, The modified particles are prepared as follows: A1: Dissolve copper sulfate pentahydrate in deionized water and adjust the pH to 9.0-9.

5. Then add ascorbic acid aqueous solution and polyvinylpyrrolidone ethanol solution dropwise and stir at 45-50℃ for 30-50 min. After centrifugation and washing of the precipitate, vacuum dry to obtain cuprous oxide nanospheres. A2: Liquid gallium metal was liquefied by heating it to 45-50℃ in an argon atmosphere, then cuprous oxide nanospheres and oleic acid were added and ultrasonically broken up to obtain coated microdroplets; A3: Add coated microdroplets to oleylamine and aluminum isopropoxide at 175-180℃ and stir for 2-2.5h. After cooling, centrifuge and wash the precipitate. Select particles of 200-500nm and treat them at 350-360℃ under argon atmosphere for 2-2.5h. After cooling, obtain modified particles.

4. The porcelain clay composition according to claim 3, characterized in that, The mass ratio of copper sulfate pentahydrate, deionized water, ascorbic acid aqueous solution, and polyvinylpyrrolidone ethanol solution in A1 is 25-30:300-360:100-120:8-9.5; The concentration of the ascorbic acid aqueous solution described in A1 is 1 mol / L; The concentration of the polyvinylpyrrolidone ethanol solution described in A1 is 0.1 mol / L.

5. The porcelain clay composition according to claim 3, characterized in that, The mass ratio of liquid gallium, cuprous oxide nanospheres, and oleic acid described in A2 is 50-60:5-6:0.5-0.

6.

6. The porcelain clay composition according to claim 3, characterized in that, The mass ratio of oleylamine, aluminum isopropoxide, and coated microdroplets described in A3 is 123-148:20.4-24.5:55-66.

7. A ceramic, characterized in that, The preparation method is as follows: S1: After the porcelain clay composition according to any one of claims 1-6 is conditioned for 12-18 hours, it is passed through a 50-60 mesh sieve, then injected into a mold and subjected to pressure treatment. After molding, it is dried and then dried at 105-110℃ to obtain a green body. S2: The green body is placed between graphite felts and sintered to obtain ceramics.

8. The ceramic according to claim 7, characterized in that, The pressure during the pressure holding process described in S1 is 28-30 MPa, and the holding time is 30-40 s.

9. The ceramic according to claim 7, characterized in that, The sintering process described in S2 is as follows: First, apply 150-200A AC current under an argon atmosphere and heat to 1850-1900℃ within 20-25s. Hold at this temperature for 60-70s and then cool to 650-670℃ under an argon atmosphere. Next, heat to 1050-1100℃ at a rate of 5-10℃ / min under an argon atmosphere and hold for 3-4h. Then, cool to 650-700℃ under an argon atmosphere at a rate of 3-5℃ / min and hold for 30-50min. Finally, cool with the furnace.

10. An application of the ceramic according to any one of claims 7-9, characterized in that, The ceramics are used in the fields of mechanical bearings, cutting tools, building pipes, and ceramic tiles.

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