Zirconium oxide composite powder, dental restoration and preparation method thereof

Abstract

The invention provides zirconium oxide composite powder, a dental restoration and a preparation method of the zirconium oxide composite powder. The apparent density of the zirconium oxide composite powder is 1-1.3 g / cm < 3 >, the sphericity degree is 80-95%, the hollowness degree is 1-10%, and the particle size is 35-75 microns. The dental prosthesis is prepared from the zirconium oxide composite powder. According to the zirconium oxide composite powder provided by the invention, the dispersity and the forming rate of the zirconium oxide powder can be improved while the use of glue is reduced, and the blank strength and the stability of the powder after compression molding can also be improved, so that the strength of the obtained dental restoration is improved.

Description

Technical Field

[0001] The invention relates to the field of zirconium oxide, and in particular to a zirconium oxide composite powder, a dental restoration and a preparation method thereof. Background Art

[0002] In recent years, high-performance ceramic materials have attracted much attention due to their unique physical and chemical properties. Among them, zirconium oxide powder, as an important ceramic material, has excellent properties such as high hardness, high strength, high temperature resistance and corrosion resistance. It has a wide range of applications in many fields, such as electronic ceramic materials, biomedical materials, ceramic cutting tools, ceramic bearings and zirconium balls.

[0003] Traditional zirconia powder usually requires a lot of glue as a binder during the molding process to ensure the molding performance of the powder; however, a large amount of glue not only increases the production cost, but may also cause certain pollution to the environment. In order to solve this problem, low-glue easy-to-mold zirconia powder came into being; however, after the glue content is significantly reduced, the powder will have problems such as poor dispersibility, difficulty in molding, and reduced strength after sintering. Therefore, higher requirements are put forward for the basic properties of the pre-added powder, such as crystal form, particle size of the stabilized zirconia powder obtained by granulation, primary particles, specific surface area, etc., as well as the choice of glue type and glue addition ratio.

[0004] Therefore, how to improve the dispersibility and molding rate of zirconium oxide powder, and how to improve the strength and stability of the green body after the powder is pressed and molded, is a problem that needs to be solved urgently in the art. Summary of the invention

[0005] The object of the present invention is to provide a zirconium oxide composite powder, a dental restoration and a preparation method thereof, which can reduce the use of glue while improving the dispersibility and molding rate of the zirconium oxide powder, and can also improve the strength and stability of the powder body after pressing and molding, thereby improving the strength of the obtained dental restoration.

[0006] To achieve the above object, the present invention provides the following technical solutions:

[0007] A zirconium oxide composite powder, wherein the bulk density of the zirconium oxide composite powder is 1 to 1.3 g / cm 3 , sphericity of 80-95%, hollowness of 1-10% and particle size of 35-75 μm.

[0008] In some embodiments of the present invention, the zirconium oxide composite powder contains zirconium oxide, a stabilizer, a dispersant and a binder.

[0009] In some embodiments of the present invention, the stabilizer is at least one of yttrium oxide, erbium oxide, and ytterbium oxide.

[0010] In some embodiments of the present invention, the dispersant is at least one of polyether acid compounds, polycarboxylic acid compounds, phosphate compounds, polyether amine compounds, and polymethacrylate compounds, preferably a polymethacrylate compound.

[0011] In some embodiments of the present invention, the binder is at least one of polyvinyl alcohol, polyethylene glycol, and polymethyl methacrylate, preferably polyvinyl alcohol.

[0012] In some embodiments of the present invention, the glass transition temperature Tg of the binder is 65-90°C.

[0013] To achieve the above object, the present invention also provides the following technical solutions:

[0014] A method for preparing the above-mentioned zirconium oxide composite powder comprises the following steps:

[0015] S1, providing stabilized zirconium oxide powder, dispersant and binder;

[0016] S2, optionally diluting the dispersant and the binder respectively with a diluent;

[0017] S3, mixing the stabilized zirconium oxide powder, water and a diluted dispersant;

[0018] S4, adding the diluted binder to the mixture obtained in step S3;

[0019] S5, drying the mixture obtained in step S4 into powder to obtain the zirconium oxide composite powder.

[0020] In some embodiments of the present invention, the preparation of the stabilized zirconium oxide powder in step S1 comprises the following steps:

[0021] A1, dissolving zirconium nitrate in water to obtain an aqueous solution of zirconium nitrate, wherein the zirconium nitrate is preferably selected from at least one of zirconium oxychloride, zirconium chloride, zirconium sulfate and zirconium nitrate;

[0022] A2, adding a stabilizer to the aqueous solution system of step A1 to form stabilized zirconium oxide;

[0023] A3, drying the stabilized zirconium oxide obtained in step A2 into powder;

[0024] A4, sintering the powder obtained in step A3;

[0025] A5, grinding and dispersing the product obtained in step A4 to obtain the stabilized zirconium oxide powder.

[0026] In some embodiments of the present invention, at least one of the following features is present:

[0027] In the step A1, the mass ratio of zirconium nitrate to water is 1:(1-7);

[0028] In the step A2, the mass ratio of the stabilizer to zirconium nitrate is (0.01-0.16):1;

[0029] In step A3, the drying equipment is any one of an oven, a microwave dryer, and a spray dryer, the drying temperature is 150 to 270° C., and the drying time is 1 to 20 hours;

[0030] In the step A4, the sintering equipment is any one of a high temperature furnace, a bell furnace, a box furnace, a push plate furnace, a roller furnace, and a rotary furnace. The sintering temperature is 900-1200° C., the heating time is 1.5-10 hours, the temperature is kept at 900-1200° C. for 0.5-4 hours, and the cooling time is 3-10 hours.

[0031] In some embodiments of the present invention, at least one of the following features is present:

[0032] The particle size D50 of the stabilized zirconia is 0.1 to 0.5 μm and the D90 is 0.2 to 1 μm;

[0033] The crystal form of the stabilized zirconium oxide comprises a monoclinic phase and a tetragonal phase, preferably comprises 0.5-4% of the monoclinic phase and 96-99.5% of the tetragonal phase;

[0034] The specific surface area of ​​the stabilized zirconium oxide is 10 to 15 m2 / g;

[0035] In some embodiments of the present invention, in step S2, the diluent is at least one of alcohols, ethers, esters, and water.

[0036] In some embodiments of the present invention, in step S2, the mass ratio of the diluent to the dispersant is (0.5-20):1;

[0037] And / or, the mass ratio of the diluent to the binder is (0.5-10):1.

[0038] In some embodiments of the present invention, in step S3, the mass ratio of the stabilized zirconia powder, water and the diluted dispersant is (80-120):(100-300):(5-10), the temperature of the mixture is controlled at 25°C, the mixing rate is 10-50Hz, and the mixing time is 0.5-10h;

[0039] And / or, the pH value of the dispersant is 7.5 to 9, preferably 7.5 to 8.5.

[0040] In some embodiments of the present invention, in step S4, the mass ratio of the stabilized zirconia powder, water, diluted dispersant and diluted binder is (80-120):(100-300):(5-10):(1-80), the temperature of the mixture is controlled at 25°C, the mixing rate is 10-50Hz, and the mixing time is 0.5-10h.

[0041] In some embodiments of the present invention, the method has at least one of the following features:

[0042] In step S5, the drying temperature is 150-270° C., and the drying time is 1-20 hours;

[0043] In the step S5, drying is performed by using any one of rotary flash evaporation, high-speed centrifugal spraying, blade drying, and boiling drying, or a combination of at least two of the methods;

[0044] In the step S5, the mesh number of the stabilized zirconium oxide powder granulated by the drying equipment is 100-500 mesh, and the particle size of the stabilized zirconium oxide powder obtained by granulation is 35-75 μm.

[0045] In order to achieve the above object, the present invention also provides the following technical solutions:

[0046] A dental restoration is made from the zirconium oxide composite powder or the zirconium oxide composite powder obtained by the method.

[0047] In order to achieve the above object, the present invention also provides the following technical solutions:

[0048] A method for preparing the above-mentioned dental restoration, the method comprising the following steps:

[0049] A10, powder dry pressing: placing the zirconium oxide composite powder into a dry pressing machine mold for pressing;

[0050] A20, cold isostatic pressing: the compressed zirconium oxide composite powder obtained in step A10 is sealed in plastic and placed in a cold isostatic press to pressurize and exhaust;

[0051] A30, bisque firing and debinding: heating the zirconia composite powder obtained in step A20 and being cooled and isostatically pressed;

[0052] A40, final firing of porcelain: firing the bisque-fired zirconium oxide composite powder obtained in step A30 to obtain a bisque;

[0053] A50, post-processing: polishing, glazing and reshaping the blank obtained in step A40 to obtain the dental restoration.

[0054] Some embodiments of the present invention have at least one of the following features:

[0055] In the step A10, the pressing pressure is 15-25 MPa;

[0056] In the step A20, the pressure of the cold isostatic pressing is 180-250 MPa;

[0057] In the step A30, the heating temperature is 1000-1100° C.;

[0058] In the step A40, the firing temperature is 1400-1500°C.

[0059] Further areas of applicability will become apparent from the description provided in the present disclosure, and the description and specific examples in this summary are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure.

[0060] Compared with the prior art, the technical solution provided by the present invention has the following beneficial effects:

[0061] The zirconium oxide composite powder provided by the present invention can reduce the use of glue, improve the dispersibility and molding rate of the zirconium oxide powder, and can also improve the strength and stability of the blank after the powder is pressed and molded, thereby improving the strength of the obtained dental restoration. BRIEF DESCRIPTION OF THE DRAWINGS

[0062] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some implementation plans of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without paying any creative work.

[0063] Figure 1 A flowchart of a method for preparing zirconium oxide composite powder according to one embodiment of the present invention. DETAILED DESCRIPTION

[0064] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by those skilled in the art without creative work belong to the scope of protection of the present invention. It should be understood that the specific embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.

[0065] Any specific numerical value disclosed herein (including the endpoint of the numerical range) is not limited to the exact value of the numerical value, but should be understood to also cover values ​​close to the exact value, such as all possible numerical values ​​within the range of ±5% of the exact value. In addition, for the disclosed numerical range, the endpoint values ​​of the range, the endpoint values ​​and the specific point values ​​in the range, and the specific point values ​​can be arbitrarily combined to obtain one or more new numerical ranges, and these new numerical ranges should also be regarded as specifically disclosed herein.

[0066] The terms used in the present disclosure are only intended to describe specific exemplary embodiments and are not intended to be limiting. Unless the context clearly indicates otherwise, the singular forms "one", "a kind of" and "the" as used in the present disclosure may be intended to also include plural forms. The terms "comprise", "include", "contain" and "have" are inclusive, thus illustrating the presence of the features, elements, compositions, steps, integers, operations and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or their collections. Although the open term "comprise" should be understood as a non-limiting term for describing and claiming the various embodiments described in the present disclosure, in some aspects, the term may be alternatively understood as a more restrictive and limited term, such as "consisting of..." or "consisting essentially of..." Thus, for any given embodiment of a narration composition, material, component, element, feature, integer, operation and / or process step, the present disclosure also particularly includes an embodiment consisting of or essentially consisting of such a composition, material, component, element, feature, integer, operation and / or process step. In the case of “consisting of,” alternative embodiments exclude any additional compositions, materials, components, elements, features, integers, operations and / or process steps, while in the case of “consisting essentially of,” any additional compositions, materials, components, elements, features, integers, operations and / or process steps that materially affect the basic and novel characteristics are excluded from such embodiments, but any compositions, materials, components, elements, features, integers, operations and / or process steps that do not materially affect the basic and novel characteristics may be included in the embodiments.

[0067] Any method steps, processes, and operations described in the present disclosure should not be construed as necessarily requiring their performance in the particular order discussed or illustrated, unless expressly identified as a certain order of performance. It should also be understood that additional or alternative steps may be used unless otherwise stated.

[0068] In this application, except for the contents explicitly described, any matters or items not mentioned are directly applicable to those known in the art without any changes. Moreover, any embodiment described in this disclosure can be freely combined with one or more other embodiments described in this disclosure, and the technical solutions or technical ideas formed thereby are regarded as part of the original disclosure or original record of this application, and should not be regarded as new contents that have not been disclosed or anticipated in this disclosure, unless a person skilled in the art considers that the combination is obviously unreasonable.

[0069] Unless otherwise specified, the terms used herein have the same meaning as commonly understood by those skilled in the art. If a term is defined herein and its definition is different from the commonly understood meaning in the art, the definition herein shall prevail.

[0070] Unless otherwise stated, when % is mentioned herein, it means wt. %.

[0071] First aspect

[0072] The present invention provides a zirconium oxide composite powder, wherein the bulk density of the zirconium oxide composite powder is 1 to 1.3 g / cm 3 , sphericity of 80-95%, hollowness of 1-10% and particle size of 35-75 μm.

[0073] It is worth noting that the bulk density of the zirconium oxide composite powder provided by the present invention is between 1 and 1.3 g / cm 3 The results show that the composite powder has a low fluffy property, the mechanical bite between particles is weakened, and the fluidity is significantly improved; the spherical particles with a shape close to an ideal sphere, low surface roughness, and small friction between particles; the hollowness of 1-10% causes micron-scale cavities to exist inside the particles, but no through pores are formed. This partially hollow structure can be quickly densified by surface diffusion and grain boundary migration at the beginning of sintering, that is, the cavity shrinks, and a small amount of closed pores (<10%) can be retained to relieve sintering stress; the particle size in the range of 35-75μm is suitable for most molding processes, such as dry pressing requires coarser particles to avoid sticking to the mold, and spraying requires a certain particle size to ensure sufficient melting; at the same time, compared with solid particles, the hollow structure increases the specific surface area, increases the surface active sites, and can accelerate densification by surface diffusion at the beginning of sintering; in addition, zirconium oxide in the tetragonal phase (t-ZrO 2 ) to monoclinic phase (m-ZrO 2 ) transformation is accompanied by a volume expansion of about 3 to 5%; moreover, the hollow structure can absorb part of the phase change stress, while the uniform stacking of spherical particles reduces local stress concentration, making the phase change toughening effect more controllable.

[0074] In some embodiments of the present invention, the zirconium oxide composite powder contains zirconium oxide, a stabilizer, a dispersant and a binder.

[0075] In some embodiments of the present invention, the stabilizer is at least one of nitrates or chlorides of yttrium, erbium, silicon, magnesium, and calcium. Preferably, the nitrate or chloride is fully soluble in the aqueous solution. For example, the zirconium oxide is at least one of yttrium nitrate stabilized zirconium oxide, erbium chloride stabilized zirconium oxide, etc. The main functions of yttrium in zirconium oxide powder are as follows:

[0076] 1. Stabilize high temperature phase and inhibit harmful phase change: pure zirconium oxide is a monoclinic phase (m-ZrO 2 ), and transforms into a tetragonal phase (t-ZrO) when heated to about 1170°C. 2 ), and then further heated to 2370℃ to transform into cubic phase (c-ZrO 2 ). When cooled, the tetragonal phase will reverse to the monoclinic phase, accompanied by a 3-5% volume expansion, resulting in stress concentration and even cracking inside the material. 3+ Partially replace Zr 4+ Because Y 3+ Due to the large radius and charge difference, oxygen vacancies are introduced into the lattice to maintain electrical neutrality. The presence of oxygen vacancies reduces the phase transition energy barrier, allowing the high-temperature tetragonal phase or cubic phase to exist stably at room temperature.

[0077] 2. Phase transformation toughening mechanism: In the yttria-partially stabilized zirconia, the metastable tetragonal phase (t-ZrO 2 ) undergoes a martensitic phase transformation (t→m) under the action of external forces (such as crack tip stress), accompanied by volume expansion. This expansion compresses the crack tip, hinders crack propagation, and significantly improves the fracture toughness of the material.

[0078] 3. Suppressing grain coarsening: Y 3+ Segregation at grain boundaries can pin grain boundary migration, inhibit abnormal grain growth during sintering, maintain a fine-grained structure (grain size <1μm), and thus improve high-temperature mechanical properties (such as creep resistance).

[0079] 4. Thermal shock resistance: The stable tetragonal phase / cubic phase and phase change toughening work together to absorb the stress caused by thermal shock and avoid failure of coatings or ceramic components due to thermal cycles.

[0080] In some embodiments of the present invention, the dispersant is at least one of polyether acid compounds, polyether compounds, ether compounds, fatty acid salt compounds, polyphosphate compounds, polycarboxylic acid compounds, phosphate ester compounds, polyether amine compounds, and polymethacrylate compounds, preferably polymethacrylate compounds. The polymethacrylate compound is, for example, sodium polymethacrylate, potassium polymethacrylate, and ammonium polymethacrylate. Anionic dispersants such as polymethacrylates have carboxylate groups (—COO - ) and the —OH or —O - Through hydrogen bonds or chemical bonds (such as coordination bonds), a thick adsorption layer with a thickness of about 10 to 50 nm is formed. This adsorption reduces the surface energy of the particles and prevents agglomeration. When the particles are close, the compression of the adsorption layer consumes energy (entropy repulsion), further preventing agglomeration. Polymethacrylate can make the Zeta potential of zirconium oxide particles reach above -40mV, significantly inhibiting agglomeration. The long chain structure of polymethacrylate forms a "flexible barrier" on the surface of the particles, resisting gravity sedimentation through Brownian motion. At the same time, its hydrophilic chain segments strongly interact with water molecules to form a hydration layer, reducing the probability of particle collision. Anionic dispersants such as polymethacrylates have good dispersibility, ensuring that the bulk density and sphericity of the powder meet the standards (such as loose density 1 to 1.3g / cm 3 ), reducing local defects during sintering. Dispersants inhibit hard agglomeration, making the powder particle size distribution narrow and the specific surface area high (such as hollow structure particles), shortening the mass transfer path during sintering, and increasing the densification rate. Polymethacrylate can be completely decomposed into CO during high-temperature sintering. 2 and H 2 O, no residual impurities (such as sodium and potassium salts need to be controlled to avoid affecting the stability of the zirconium oxide phase). Other types of dispersants may be less preferred due to weak adsorption (such as polyethers), poor stability (such as phosphates), and the introduction of impurities (such as polyphosphates).

[0081] In some embodiments of the present invention, the binder is at least one of polyvinyl alcohol, polyethylene glycol, cellulose, alginates, and polymethyl methacrylate, preferably polyvinyl alcohol. The dense hydroxyl groups (—OH) on the molecular chain of polyvinyl alcohol (PVA) can form a strong hydrogen bond network with the —OH on the surface of zirconium oxide, and at the same time form a flexible polymer chain bridge between the powders. This dual effect (surface adsorption + chain entanglement) imparts high bonding strength, and the surface tension of the PVA aqueous solution (about 40-50 mN / m) and the surface energy of zirconium oxide (about 60 mJ / m 2) can fully wet the particle surface, reduce porosity, and thus improve the green strength of the powder. The aqueous solution of PVA has pseudoplastic fluid properties (shear thinning), which can reduce friction between powders and promote uniform filling during dry pressing or injection molding. Other binders may be less preferred due to weak bonding (PEG), complex process (PMMA), and poor stability (alginate).

[0082] In the context of the present invention, polyethylene glycol is also referred to as polyethylene oxide or polyoxyethylene.

[0083] In some embodiments of the present invention, the cellulose is at least one of hydroxymethyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, carboxymethyl cellulose, carboxyethyl cellulose, carboxypropyl cellulose, methyl cellulose, and ethyl cellulose. In the context of the present invention, the above cellulose includes the form of its salt, such as sodium salt, potassium salt, and ammonium salt.

[0084] In some embodiments of the present invention, alginate includes, for example, sodium alginate, potassium alginate, calcium alginate, ammonium alginate. The source of alginate is not particularly limited and can be biological or synthetic. Alginate can be optionally modified, for example, by introducing chemical functional groups.

[0085] In some embodiments of the present invention, the glass transition temperature Tg of the binder is 65-90° C. During dry pressing or injection molding, the local temperature may be close to Tg, at which time the binder part enters a highly elastic state, the flexibility of the molecular chain increases, the particles are rearranged through the viscoelastic creep of the binder film, the drying stress is released, and the gaps between the particles are filled through viscoelastic flow, avoiding microcracks caused by too fast solvent evaporation, thereby increasing the green density.

[0086] In some embodiments of the present invention, the zirconium oxide composite powder comprises 85-100% zirconium oxide, 1-16% stabilizer, 0.05-1.5% dispersant, and 0.05-1.0% binder. In some embodiments of the present invention, the content of the above components is based on 100% by weight of the zirconium oxide composite powder. In some preferred embodiments, the total amount of zirconium oxide, stabilizer, dispersant and binder is 100% by weight.

[0087] In some embodiments of the present invention, the dispersant will be adsorbed on the surface of the zirconium oxide particles, especially the stabilized zirconium oxide particles. In particular, the adsorbent in the above preferred content range helps to form steric hindrance or electrostatic repulsion, so that the particles are in a suspended state, preventing the particles from settling, and the slurry has better fluidity and lower viscosity. When the dispersant is in the above preferred range, it helps to ensure the hydrophilicity of the zirconium oxide particles and prevent the particles from forming larger agglomerates. After drying, the sphericity ratio of the mixed liquid is ≥80%, the hollowness ratio is <10%, and the powder forming rate is ≥95% after dry pressing, isostatic pressing, and pre-sintering stages.

[0088] In some embodiments of the present invention, the glass transition temperature Tg of the binder is 65-90°C. When the glass transition temperature of the binder is within the above range, it is advantageous to avoid or alleviate the defects of the mixed slurry during the drying process, such as cracks and deformation of the blank due to uneven drying, improve the strength of the dried zirconium oxide particles, and reduce the number of "apple-shaped balls", "shrunken balls", and "agglomerates of multiple balls". The sphericity ratio of the powder produced by using the binder with the above glass transition temperature Tg and the preferred content range is ≥80%-95%, and the hollowness ratio is ≤10%.

[0089] In some embodiments of the present invention, the zirconium oxide comprises monoclinic zirconium oxide and tetragonal zirconium oxide, preferably 0.5% to 4% of monoclinic zirconium oxide and 96% to 99.5% of tetragonal zirconium oxide.

[0090] Second aspect

[0091] See also Figure 1 The present invention provides a method for preparing the zirconium oxide composite powder of the present invention, comprising the following steps: S1, providing stabilized zirconium oxide powder, a dispersant and a binder; S2, optionally diluting the dispersant and the binder with a diluent respectively; S3, mixing the stabilized zirconium oxide powder, water and the optionally diluted dispersant; S4, adding the optionally diluted binder to the mixture obtained in step S3; S5, drying the mixture obtained in step S4 into powder to obtain the zirconium oxide composite powder.

[0092] In some embodiments of the present invention, the preparation of the stabilized zirconium oxide powder in step S1 includes the following steps: A1, dissolving zirconium nitrate in water to obtain an aqueous solution of zirconium nitrate; A2, adding a stabilizer to the aqueous solution system of step A1; A3, drying the mixture obtained in step A2 into powder; A4, sintering the powder obtained in step A3; A5, grinding and dispersing the product obtained in step A4 to obtain the stabilized zirconium oxide powder.

[0093] In some preferred embodiments of the present invention, the zirconium nitrate is selected from at least one of zirconium oxychloride, zirconium chloride, zirconium sulfate and zirconium nitrate.

[0094] In some embodiments of the present invention, the zirconium oxide is prepared by coprecipitation, hydrolysis precipitation, hydrothermal or sol-gel method, preferably by hydrothermal method. In the hydrothermal method, zirconium ions in zirconium nitrate solution react under high temperature and high pressure conditions to form zirconium oxide crystals. The specific conditions of the hydrothermal method are well known to those skilled in the art.

[0095] In some embodiments of the present invention, the hydrothermal reaction is carried out in a hydrothermal reactor. In some embodiments of the present invention, the hydrothermal reaction is carried out under the autogenous pressure of the hydrothermal reactor, and the specific pressure is not limited. The pressure of the hydrothermal reaction is, for example, 0.1 to 2 MPa, such as 0.5 MPa, 1 MPa, 1.5 MPa.

[0096] In some embodiments of the present invention, in step A1, the mass ratio of zirconium nitrate to water is 1:(1-7), which ensures the solid content of the slurry while improving the stability of the powder during the reaction process.

[0097] In some embodiments of the present invention, in step A2, the mass ratio of the stabilizer to zirconium nitrate is (0.01-0.16):1, and the temperature is gradually increased to 170° C. and kept for 30 hours for the synthesis reaction.

[0098] In some embodiments of the present invention, in step A3, the drying equipment is any one of an oven, a microwave dryer, and a spray dryer, the drying temperature is 150 to 270° C., and the drying time is 1 to 20 hours. The drying equipment is preferably a spray dryer, which has high drying efficiency and is not easy to introduce impurities.

[0099] In some embodiments of the present invention, in step A4, the sintering equipment is any one of a high-temperature furnace, a bell furnace, a box furnace, a push-plate furnace, a roller furnace, and a rotary furnace, the sintering temperature is 900-1200°C, the heating time is 1.5-10 hours, the temperature is kept at 900-1200°C for 0.5-4 hours, and the cooling time is 3-10 hours.

[0100] In some embodiments of the present invention, the particle size D50 of the stabilized zirconia is 0.1-0.5 μm and the particle size D90 is 0.2-1 μm.

[0101] In some embodiments of the present invention, the stabilized zirconia comprises monoclinic zirconia and tetragonal zirconia, preferably 0.5-4% monoclinic zirconia and 96-99.5% tetragonal zirconia.

[0102] In some embodiments of the present invention, the specific surface area of ​​the stabilized zirconia is 10 to 15 m 2 / g.

[0103] In some embodiments of the present invention, in step S2, the diluent is at least one of alcohols, ethers, esters, and water.

[0104] In some embodiments of the present invention, in step S2, the mass ratio of the diluent to the dispersant is (0.5-20):1.

[0105] In some embodiments of the present invention, the mass ratio of the diluent to the binder is (0.5-10):1.

[0106] In some embodiments of the present invention, in step S3, the mass ratio of the stabilized zirconia powder, water and diluted dispersant is (80-120):(100-300):(5-10), the temperature of the mixture is controlled at 10-50°C, for example, 25°C, the mixing rate is 10-50Hz, and the mixing time is 0.5-10h.

[0107] In some embodiments of the present invention, the pH value of the dispersant is 7.5 to 9, preferably 7.5 to 8.5. Increasing the amount of polymethacrylate dispersant will increase the pH value of the system, which is mainly affected by Na + Affected by carboxylate hydrolysis.

[0108] Advantageously, when the pH value of the dispersant satisfies the above range, it helps to improve the dispersing ability of the dispersant, inhibit the agglomeration of zirconium oxide particles, and increase the stability of the dispersion system. In addition, the pH range of the dispersant helps to avoid the degradation of the dispersant molecular chain or other chemical reactions, and maintain the beneficial effects of the dispersant. The powder has a molding rate of ≥95% after dry pressing, isostatic pressing, and pre-sintering.

[0109] In some embodiments of the present invention, in step S4, the mass ratio of the stabilized zirconia powder, water, diluted dispersant and diluted binder is (80-120):(100-300):(5-10):(1-80), the temperature of the mixture is controlled at 10-50°C, for example, 25°C, the mixing rate is 10-50Hz, and the mixing time is 0.5-10h.

[0110] In the above steps S3 and S4, maintaining the temperature and mixing rate within the above favorable range helps to improve the support of the primary particles in the process of drying into larger particles, and obtains powders with high sphericity, high gloss, low local depression ratio, and a molding rate of ≥95% in the dry pressing, isostatic pressing and biscuit sintering stages.

[0111] In some embodiments of the present invention, in step S5, the drying temperature is 150-270° C., and the drying time is 1-20 hours.

[0112] In some embodiments of the present invention, in step S5, drying is performed by using any one of rotary flash evaporation, high-speed centrifugal spraying, blade drying, and boiling drying, or a combination of at least two of the methods.

[0113] In some embodiments of the present invention, in step S5, the mesh number of the stabilized zirconia powder granulated by the drying equipment is 100-500 mesh, and the particle size of the stabilized zirconia powder obtained by granulation is 35-75 μm.

[0114] The third aspect

[0115] The present invention provides a dental restoration, which is made from the zirconium oxide composite powder or the zirconium oxide composite powder obtained by the above method.

[0116] The fourth aspect

[0117] The present invention provides a method for preparing the above-mentioned dental restoration, which comprises the following steps: A10, powder dry pressing molding: placing the zirconium oxide composite powder into a dry pressing machine mold for pressing; A20, cold isostatic pressing: sealing the compressed zirconium oxide composite powder obtained in step A10, placing it into a cold isostatic press for pressurization and exhaust; A30, bisque firing and debinding: heating the cold isostatically pressed zirconium oxide composite powder obtained in step A20; A40, final firing and porcelainization: firing the bisque fired zirconium oxide composite powder obtained in step A30 to obtain a bisque blank; A50, post-processing: polishing, glazing and shaping the bisque blank obtained in step A40 to obtain the dental restoration.

[0118] In some embodiments of the present invention, in step A10, the pressing pressure is 15-25 MPa.

[0119] In some embodiments of the present invention, in step A20, the pressure of cold isostatic pressing is 180-250 MPa.

[0120] In some embodiments of the present invention, in step A30, the heating temperature is 1000-1100°C.

[0121] In some embodiments of the present invention, in step A40, the firing temperature is 1400-1500°C.

[0122] In some embodiments of the present invention, there is a step A35 between step A30 and step A40, and step A35 is carving: carving is performed on the bisque-fired zirconium oxide composite powder obtained in step A30; and in step A40, the carved zirconium oxide composite powder obtained in step A35 is fired to obtain the bisque.

[0123] Example 1

[0124] The present embodiment provides a method for preparing a zirconia composite powder, comprising the following steps: S1, providing stabilized zirconia powder, a dispersant and a binder; S2, diluting the dispersant and the binder with a diluent; S3, mixing the stabilized zirconia powder, water and the diluted dispersant; S4, adding the diluted binder to the mixture obtained in step S3; S5, drying the mixture obtained in step S4 into powder to obtain the zirconia composite powder. Sodium polymethacrylate is used as a dispersant, and polyvinyl alcohol is used as a binder. The Tg of the binder used is 85°C.

[0125] The preparation of the stabilized zirconium oxide powder in step S1 includes the following steps: A1, dissolving zirconium nitrate in water to obtain an aqueous solution of zirconium nitrate; A2, adding a stabilizer to the aqueous solution system of step A1 to form stabilized zirconium oxide; A3, drying the mixture obtained in step A2 into powder; A4, sintering the powder obtained in step A3; A5, grinding and dispersing the product obtained in step A4 to obtain the stabilized zirconium oxide powder.

[0126] Wherein, in step A1, the mass ratio of zirconium nitrate to water is 1:1, the ambient temperature is 10° C., the stirring rate is 10 Hz, and the reaction time is 0.5 h.

[0127] Wherein, in step A2, the mass ratio of the stabilizer to zirconium nitrate is 0.01:1.

[0128] Wherein, in step A3, the drying equipment is any one of an oven, a microwave dryer, and a spray dryer, the drying temperature is 150° C., and the drying time is 1 hour.

[0129] Wherein, in step A4, the sintering equipment is a rotary kiln, the sintering temperature is 900°C, the heating time is 1.5 hours, the temperature is kept at 900°C for 0.5 hours, and the cooling time is 3 hours.

[0130] Wherein, in the step A5, the mesh number of the ground stabilized zirconia powder is 450 mesh, and the particle size of the stabilized zirconia powder obtained by granulation is 35 μm.

[0131] The D50 of the stabilized zirconia is 0.1 μm and the D90 is 0.2 μm; the stabilized zirconia contains 4.0% monoclinic phase and 96% tetragonal phase; the specific surface area of ​​the stabilized zirconia is 14 m 2 / g.

[0132] Wherein, in step S2, the diluent is pure water.

[0133] Wherein, in step S2, the mass ratio of the diluent to the dispersant is 0.5:1, and the mass ratio of the diluent to the binder is 0.5:1.

[0134] Wherein, in the step S3, the mass ratio of the stabilized zirconium oxide powder, water and the diluted dispersant is 100:100:1, the temperature of the mixture is controlled at 25°C, the mixing rate is 10-50Hz, and the mixing time is 5h.

[0135] The pH value of the dispersant is 7.5.

[0136] Wherein, in step S4, the mass ratio of the stabilized zirconia powder, water, diluted dispersant and diluted binder is 100:100:1:1, the temperature of the mixture is controlled at 25°C, the mixing rate is 10 Hz, and the mixing time is 0.5 h.

[0137] Wherein, in step S5, the drying temperature is 150° C. and the drying time is 1 hour.

[0138] Wherein, in the step S5, drying is performed by high-speed centrifugal spraying.

[0139] Example 2

[0140] This embodiment provides a method for preparing a zirconia composite powder, comprising the following steps: S1, providing stabilized zirconia powder, a dispersant and a binder; S2, diluting the dispersant and the binder with a diluent; S3, mixing the stabilized zirconia powder, water and the diluted dispersant; S4, adding the diluted binder to the mixture obtained in step S3; S5, drying the mixture obtained in step S4 into powder to obtain the zirconia composite powder. Sodium polymethacrylate is used as a dispersant, and polyvinyl alcohol is used as a binder. The Tg of the binder used is 88°C.

[0141] The preparation of the stabilized zirconium oxide powder in step S1 includes the following steps: A1, dissolving zirconium nitrate in water to obtain an aqueous solution of zirconium nitrate; A2, adding a stabilizer to the aqueous solution system of step A1 to form stabilized zirconium oxide; A3, drying the mixture obtained in step A2 into powder; A4, sintering the powder obtained in step A3; A5, grinding and dispersing the product obtained in step A4 to obtain the stabilized zirconium oxide powder.

[0142] Wherein, in step A1, the mass ratio of zirconium nitrate to water is 1:2, the ambient temperature is 15° C., the stirring rate is 15 Hz, and the reaction time is 0.5 h.

[0143] Wherein, in step A2, the mass ratio of the stabilizer to zirconium nitrate is 0.02:1.

[0144] Wherein, in step A3, the drying equipment is any one of an oven, a microwave dryer, and a spray dryer, the drying temperature is 150° C., and the drying time is 1.5 h.

[0145] Wherein, in step A4, the sintering equipment is a rotary kiln, the sintering temperature is 900°C, the heating time is 1.5 hours, the temperature is kept at 900°C for 0.5 hours, and the cooling time is 3 hours.

[0146] Wherein, in the step A5, the mesh size of the ground stabilized zirconia powder is 400 mesh, and the particle size of the stabilized zirconia powder obtained by granulation is 36 μm.

[0147] The D50 of the stabilized zirconia is 0.12 μm and the D90 is 0.2 μm; the stabilized zirconia contains 3.5% monoclinic phase and 96.4% tetragonal phase; the specific surface area of ​​the stabilized zirconia is 13 m 2 / g.

[0148] Wherein, in step S2, the diluent is pure water.

[0149] Wherein, in step S2, the mass ratio of the diluent to the dispersant is 1:1, and the mass ratio of the diluent to the binder is 1:1.

[0150] Wherein, in the step S3, the mass ratio of the stabilized zirconia powder, water and the diluted dispersant is 100:200:2, the temperature of the mixture is controlled at 25°C, the mixing rate is 10-50Hz, and the mixing time is 5h.

[0151] Wherein, a dispersant is used to adjust the pH value of the solution system in step S3 to 7.7.

[0152] Wherein, in step S4, the mass ratio of the stabilized zirconia powder, water, diluted dispersant and diluted binder is 100:200:2:2, the temperature of the mixture is controlled at 25°C, the mixing rate is 15 Hz, and the mixing time is 1 hour.

[0153] Wherein, in step S5, the drying temperature is 150° C. and the drying time is 2 hours.

[0154] Wherein, in the step S5, drying is performed by high-speed centrifugal spraying.

[0155] Example 3

[0156] This embodiment provides a method for preparing a zirconia composite powder, comprising the following steps: S1, providing stabilized zirconia powder, a dispersant and a binder; S2, diluting the dispersant and the binder with a diluent; S3, mixing the stabilized zirconia powder, water and the diluted dispersant; S4, adding the diluted binder to the mixture obtained in step S3; S5, drying the mixture obtained in step S4 into powder to obtain the zirconia composite powder. Sodium polymethacrylate is used as a dispersant, and polyvinyl alcohol is used as a binder. The Tg of the binder used is 71°C.

[0157] The preparation of the stabilized zirconium oxide powder in step S1 includes the following steps: A1, dissolving zirconium nitrate in water to obtain an aqueous solution of zirconium nitrate; A2, adding a stabilizer to the aqueous solution system of step A1 to form stabilized zirconium oxide; A3, drying the mixture obtained in step A2 into powder; A4, sintering the powder obtained in step A3; A5, grinding and dispersing the product obtained in step A4 to obtain the stabilized zirconium oxide powder.

[0158] Wherein, in step A1, the mass ratio of zirconium nitrate to water is 1:2, the ambient temperature is 17° C., the stirring rate is 15 Hz, and the reaction time is 1 h.

[0159] Wherein, in step A2, the mass ratio of the stabilizer to zirconium nitrate is 0.03:1.

[0160] Wherein, in step A3, the drying equipment is any one of an oven, a microwave dryer, and a spray dryer, the drying temperature is 200° C., and the drying time is 2 hours.

[0161] Wherein, in step A4, the sintering equipment is a rotary kiln, the sintering temperature is 1000°C, the heating time is 1.5 hours, the temperature is kept at 1000°C for 1.5 hours, and the cooling time is 3 hours.

[0162] Wherein, in the step A5, the mesh number of the ground stabilized zirconia powder is 380 mesh, and the particle size of the stabilized zirconia powder obtained by granulation is 40 μm.

[0163] The D50 of the stabilized zirconia is 0.2 μm and the D90 is 0.22 μm; the stabilized zirconia contains 3.0% monoclinic phase and 96.5% tetragonal phase; the specific surface area of ​​the stabilized zirconia is 12 m 2 / g.

[0164] Wherein, in step S2, the diluent is pure water.

[0165] Wherein, in step S2, the mass ratio of the diluent to the dispersant is 2:1, and the mass ratio of the diluent to the binder is 2:1.

[0166] Wherein, in the step S3, the mass ratio of the stabilized zirconia powder, water and the diluted dispersant is 100:200:3, the temperature of the mixture is controlled at 25°C, the mixing rate is 10-50Hz, and the mixing time is 5h.

[0167] Wherein, a dispersant is used to adjust the pH value of the solution system in step S3 to 7.9.

[0168] Wherein, in step S4, the mass ratio of the stabilized zirconia powder, water, diluted dispersant and diluted binder is 100:200:3:3, the temperature of the mixture is controlled at 25°C, the mixing rate is 20Hz, and the mixing time is 2h.

[0169] Wherein, in step S5, the drying temperature is 200° C. and the drying time is 3 hours.

[0170] Wherein, in the step S5, drying is performed by high-speed centrifugal spraying.

[0171] Example 4

[0172] This embodiment provides a method for preparing a zirconia composite powder, comprising the following steps: S1, providing stabilized zirconia powder, a dispersant and a binder; S2, diluting the dispersant and the binder with a diluent; S3, mixing the stabilized zirconia powder, water and the diluted dispersant; S4, adding the diluted binder to the mixture obtained in step S3; S5, drying the mixture obtained in step S4 into powder to obtain the zirconia composite powder. Sodium polymethacrylate is used as a dispersant, and polyvinyl alcohol is used as a binder. The Tg of the binder used is 74°C.

[0173] The preparation of the stabilized zirconium oxide powder in step S1 includes the following steps: A1, dissolving zirconium nitrate in water to obtain an aqueous solution of zirconium nitrate; A2, adding a stabilizer to the aqueous solution system of step A1 to form stabilized zirconium oxide; A3, drying the mixture obtained in step A2 into powder; A4, sintering the powder obtained in step A3; A5, grinding and dispersing the product obtained in step A4 to obtain the stabilized zirconium oxide powder.

[0174] Wherein, in step A1, the mass ratio of zirconium nitrate to water is 1:2, the ambient temperature is 20° C., the stirring rate is 20 Hz, and the reaction time is 2 h.

[0175] Wherein, in step A2, the mass ratio of the stabilizer to zirconium nitrate is 0.03:1.

[0176] Wherein, in step A3, the drying equipment is any one of an oven, a microwave dryer, and a spray dryer, the drying temperature is 200° C., and the drying time is 2 hours.

[0177] Wherein, in step A4, the sintering equipment is a rotary kiln, the sintering temperature is 1000°C, the heating time is 2.0 hours, the temperature is kept at 1000°C for 1.5 hours, and the cooling time is 3 hours.

[0178] Wherein, in the step A5, the mesh number of the ground stabilized zirconia powder is 370 mesh, and the particle size of the stabilized zirconia powder obtained by granulation is 50 μm.

[0179] The D50 of the stabilized zirconia is 0.2 μm and the D90 is 0.30 μm; the stabilized zirconia contains 2.0% monoclinic phase and 97.5% tetragonal phase; the specific surface area of ​​the stabilized zirconia is 12 m 2 / g.

[0180] Wherein, in step S2, the diluent is pure water.

[0181] Wherein, in step S2, the mass ratio of the diluent to the dispersant is 3:1, and the mass ratio of the diluent to the binder is 3:1.

[0182] Wherein, in the step S3, the mass ratio of the stabilized zirconia powder, water and the diluted dispersant is 100:200:4, the temperature of the mixture is controlled at 25°C, the mixing rate is 10-50Hz, and the mixing time is 5h.

[0183] Wherein, a dispersant is used to adjust the pH value of the solution system in step S3 to 8.2.

[0184] Wherein, in step S4, the mass ratio of the stabilized zirconia powder, water, diluted dispersant and diluted binder is 100:200:4:4, the temperature of the mixture is controlled at 25°C, the mixing rate is 20Hz, and the mixing time is 2h.

[0185] Wherein, in step S5, the drying temperature is 200° C. and the drying time is 3 hours.

[0186] Wherein, in the step S5, drying is performed by high-speed centrifugal spraying.

[0187] Example 5

[0188] This embodiment provides a method for preparing a zirconia composite powder, comprising the following steps: S1, providing stabilized zirconia powder, a dispersant and a binder; S2, diluting the dispersant and the binder with a diluent; S3, mixing the stabilized zirconia powder, water and the diluted dispersant; S4, adding the diluted binder to the mixture obtained in step S3; S5, drying the mixture obtained in step S4 into powder to obtain the zirconia composite powder. Sodium polymethacrylate is used as a dispersant, and polyvinyl alcohol is used as a binder. The Tg of the binder used is 77°C.

[0189] The preparation of the stabilized zirconium oxide powder in step S1 includes the following steps: A1, dissolving zirconium nitrate in water to obtain an aqueous solution of zirconium nitrate; A2, adding a stabilizer to the aqueous solution system of step A1 to form stabilized zirconium oxide; A3, drying the mixture obtained in step A2 into powder; A4, sintering the powder obtained in step A3; A5, grinding and dispersing the product obtained in step A4 to obtain the stabilized zirconium oxide powder.

[0190] Wherein, in step A1, the mass ratio of zirconium nitrate to water is 1:3, the ambient temperature is 30° C., the stirring rate is 30 Hz, and the reaction time is 3 h.

[0191] Wherein, in step A2, the mass ratio of the stabilizer to zirconium nitrate is 0.03:1.

[0192] Wherein, in step A3, the drying equipment is any one of an oven, a microwave dryer, and a spray dryer, the drying temperature is 200° C., and the drying time is 2 hours.

[0193] Wherein, in step A4, the sintering equipment is a rotary kiln, the sintering temperature is 1000°C, the heating time is 2.0 hours, the temperature is kept at 1000°C for 1.5 hours, and the cooling time is 3 hours.

[0194] Wherein, in the step A5, the mesh number of the ground stabilized zirconia powder is 350 mesh, and the particle size of the stabilized zirconia powder obtained by granulation is 40 μm.

[0195] The D50 of the stabilized zirconia is 0.22 μm and the D90 is 0.30 μm; the stabilized zirconia contains 1.5% monoclinic phase and 98% tetragonal phase; the specific surface area of ​​the stabilized zirconia is 12 m 2 / g.

[0196] Wherein, in step S2, the diluent is pure water.

[0197] Wherein, in step S2, the mass ratio of the diluent to the dispersant is 3:1, and the mass ratio of the diluent to the binder is 3:1.

[0198] Wherein, in the step S3, the mass ratio of the stabilized zirconia powder, water and the diluted dispersant is 100:300:4, the temperature of the mixture is controlled at 25°C, the mixing rate is 10-50Hz, and the mixing time is 5h.

[0199] Wherein, a dispersant is used to adjust the pH value of the solution system in step S3 to 8.3.

[0200] Wherein, in step S4, the mass ratio of the stabilized zirconia powder, water, diluted dispersant and diluted binder is 100:300:4:4, the temperature of the mixture is controlled at 25°C, the mixing rate is 20Hz, and the mixing time is 2h.

[0201] Wherein, in step S5, the drying temperature is 200° C. and the drying time is 4 hours.

[0202] Wherein, in the step S5, drying is performed by high-speed centrifugal spraying.

[0203] Example 6

[0204] The present embodiment provides a method for preparing a zirconia composite powder, comprising the following steps: S1, providing stabilized zirconia powder, a dispersant and a binder; S2, diluting the dispersant and the binder with a diluent; S3, mixing the stabilized zirconia powder, water and the diluted dispersant; S4, adding the diluted binder to the mixture obtained in step S3; S5, drying the mixture obtained in step S4 into powder to obtain the zirconia composite powder. Sodium polymethacrylate is used as a dispersant, and polyvinyl alcohol is used as a binder. The Tg of the binder used is 80°C.

[0205] The preparation of the stabilized zirconium oxide powder in step S1 includes the following steps: A1, dissolving zirconium nitrate in water to obtain an aqueous solution of zirconium nitrate; A2, adding a stabilizer to the aqueous solution system of step A1 to form stabilized zirconium oxide; A3, drying the mixture obtained in step A2 into powder; A4, sintering the powder obtained in step A3; A5, grinding and dispersing the product obtained in step A4 to obtain the stabilized zirconium oxide powder.

[0206] Wherein, in step A1, the mass ratio of zirconium nitrate to water is 1:3, the ambient temperature is 30° C., the stirring rate is 30 Hz, and the reaction time is 4 hours.

[0207] Wherein, in step A2, the mass ratio of the stabilizer to zirconium nitrate is 0.04:1.

[0208] Wherein, in step A3, the drying equipment is any one of an oven, a microwave dryer, and a spray dryer, the drying temperature is 205° C., and the drying time is 3 hours.

[0209] Wherein, in step A4, the sintering equipment is a rotary kiln, the sintering temperature is 1100° C., the heating time is 3.0 hours, the temperature is kept at 1100° C. for 3 hours, and the cooling time is 3 hours.

[0210] Wherein, in the step A5, the mesh number of the ground stabilized zirconia powder is 330 mesh, and the particle size of the stabilized zirconia powder obtained by granulation is 50 μm.

[0211] The D50 of the stabilized zirconia is 0.23 μm and the D90 is 0.40 μm; the stabilized zirconia contains 1.0% monoclinic phase and 98.5% tetragonal phase; the specific surface area of ​​the stabilized zirconia is 11.5 m 2 / g.

[0212] Wherein, in step S2, the diluent is pure water.

[0213] Wherein, in step S2, the mass ratio of the diluent to the dispersant is 3:1, and the mass ratio of the diluent to the binder is 3:1.

[0214] Wherein, in the step S3, the mass ratio of the stabilized zirconia powder, water and the diluted dispersant is 100:300:4, the temperature of the mixture is controlled at 25°C, the mixing rate is 10-50Hz, and the mixing time is 5h.

[0215] Wherein, a dispersant is used to adjust the pH value of the solution system in step S3 to 8.5.

[0216] Wherein, in step S4, the mass ratio of the stabilized zirconia powder, water, diluted dispersant and diluted binder is 100:300:4:4, the temperature of the mixture is controlled at 25°C, the mixing rate is 20Hz, and the mixing time is 2h.

[0217] Wherein, in step S5, the drying temperature is 200° C. and the drying time is 4 hours.

[0218] Wherein, in the step S5, drying is performed by high-speed centrifugal spraying.

[0219] Example 7

[0220] This embodiment provides a method for preparing a zirconia composite powder, comprising the following steps: S1, providing stabilized zirconia powder, a dispersant and a binder; S2, diluting the dispersant and the binder with a diluent; S3, mixing the stabilized zirconia powder, water and the diluted dispersant; S4, adding the diluted binder to the mixture obtained in step S3; S5, drying the mixture obtained in step S4 into powder to obtain the zirconia composite powder. Sodium polymethacrylate is used as a dispersant, and polyvinyl alcohol is used as a binder. The Tg of the binder used is 83°C.

[0221] The preparation of the stabilized zirconium oxide powder in step S1 includes the following steps: A1, dissolving zirconium nitrate in water to obtain an aqueous solution of zirconium nitrate; A2, adding a stabilizer to the aqueous solution system of step A1 to form stabilized zirconium oxide; A3, drying the mixture obtained in step A2 into powder; A4, sintering the powder obtained in step A3; A5, grinding and dispersing the product obtained in step A4 to obtain the stabilized zirconium oxide powder.

[0222] Wherein, in step A1, the mass ratio of zirconium nitrate to water is 1:3, the ambient temperature is 30° C., the stirring rate is 30 Hz, and the reaction time is 4.5 h.

[0223] Wherein, in step A2, the mass ratio of the stabilizer to zirconium nitrate is 0.06:1.

[0224] Wherein, in step A3, the drying equipment is any one of an oven, a microwave dryer, and a spray dryer, the drying temperature is 210° C., and the drying time is 5 hours.

[0225] Wherein, in step A4, the sintering equipment is a rotary kiln, the sintering temperature is 1100° C., the heating time is 3.0 hours, the temperature is kept at 1100° C. for 3 hours, and the cooling time is 3 hours.

[0226] Wherein, in the step A5, the mesh size of the ground stabilized zirconia powder is 300 mesh, and the particle size of the stabilized zirconia powder obtained by granulation is 50 μm.

[0227] The D50 of the stabilized zirconia is 0.24 μm and the D90 is 0.40 μm; the stabilized zirconia contains 0.8% monoclinic phase and 98.5% tetragonal phase; and the specific surface area of ​​the stabilized zirconia is 11.5 m2 / g.

[0228] Wherein, in step S2, the diluent is pure water.

[0229] Wherein, in step S2, the mass ratio of the diluent to the dispersant is 5:1, and the mass ratio of the diluent to the binder is 5:1.

[0230] Wherein, in the step S3, the mass ratio of the stabilized zirconia powder, water and the diluted dispersant is 100:300:6, the temperature of the mixture is controlled at 25°C, the mixing rate is 10-50Hz, and the mixing time is 5h.

[0231] Wherein, a dispersant is used to adjust the pH value of the solution system in step S3 to 8.5.

[0232] Wherein, in step S4, the mass ratio of the stabilized zirconia powder, water, diluted dispersant and diluted binder is 100:300:6:4.1, the temperature of the mixture is controlled at 25°C, the mixing rate is 30 Hz, and the mixing time is 2 hours.

[0233] Wherein, in step S5, the drying temperature is 205° C. and the drying time is 6 hours.

[0234] Wherein, in the step S5, drying is performed by high-speed centrifugal spraying.

[0235] Example 8

[0236] This embodiment provides a method for preparing a zirconia composite powder, comprising the following steps: S1, providing stabilized zirconia powder, a dispersant and a binder; S2, diluting the dispersant and the binder with a diluent; S3, mixing the stabilized zirconia powder, water and the diluted dispersant; S4, adding the diluted binder to the mixture obtained in step S3; S5, drying the mixture obtained in step S4 into powder to obtain the zirconia composite powder. Sodium polymethacrylate is used as a dispersant, and polyvinyl alcohol is used as a binder. The Tg of the binder used is 86°C.

[0237] The preparation of the stabilized zirconium oxide powder in step S1 includes the following steps: A1, dissolving zirconium nitrate in water to obtain an aqueous solution of zirconium nitrate; A2, adding a stabilizer to the aqueous solution system of step A1 to form stabilized zirconium oxide; A3, drying the mixture obtained in step A2 into powder; A4, sintering the powder obtained in step A3; A5, grinding and dispersing the product obtained in step A4 to obtain the stabilized zirconium oxide powder.

[0238] Wherein, in step A1, the mass ratio of zirconium nitrate to water is 1:4, the ambient temperature is 35° C., the stirring rate is 32 Hz, and the reaction time is 4.5 h.

[0239] Wherein, in step A2, the mass ratio of the stabilizer to zirconium nitrate is 0.06:1.

[0240] Wherein, in step A3, the drying equipment is any one of an oven, a microwave dryer, and a spray dryer, the drying temperature is 210° C., and the drying time is 5 hours.

[0241] Wherein, in step A4, the sintering equipment is a rotary kiln, the sintering temperature is 1100° C., the heating time is 3.5 hours, the temperature is kept at 1100° C. for 3 hours, and the cooling time is 3 hours.

[0242] Wherein, in the step A5, the mesh number of the ground stabilized zirconia powder is 280 mesh, and the particle size of the stabilized zirconia powder obtained by granulation is 50 μm.

[0243] The D50 of the stabilized zirconia is 0.24 μm and the D90 is 0.40 μm; the stabilized zirconia contains 0.5% monoclinic phase and 99.0% tetragonal phase; the specific surface area of ​​the stabilized zirconia is 11.5 m 2 / g.

[0244] Wherein, in step S2, the diluent is pure water.

[0245] Wherein, in step S2, the mass ratio of the diluent to the dispersant is 5:1, and the mass ratio of the diluent to the binder is 5:1.

[0246] Wherein, in the step S3, the mass ratio of the stabilized zirconium oxide powder, water and the diluted dispersant is 100:300:6.5, the temperature of the mixture is controlled at 25°C, the mixing rate is 10-50Hz, and the mixing time is 5h.

[0247] Wherein, a dispersant is used to adjust the pH value of the solution system in step S3 to 8.0.

[0248] Wherein, in step S4, the mass ratio of the stabilized zirconia powder, water, diluted dispersant and diluted binder is 100:300:6.5:4.3, the temperature of the mixture is controlled at 25°C, the mixing rate is 32Hz, and the mixing time is 2h.

[0249] Wherein, in step S5, the drying temperature is 205° C. and the drying time is 6 hours.

[0250] Wherein, in the step S5, drying is performed by high-speed centrifugal spraying.

[0251] Example 9

[0252] The present embodiment provides a method for preparing a zirconia composite powder, comprising the following steps: S1, providing stabilized zirconia powder, a dispersant and a binder; S2, diluting the dispersant and the binder with a diluent; S3, mixing the stabilized zirconia powder, water and the diluted dispersant; S4, adding the diluted binder to the mixture obtained in step S3; S5, drying the mixture obtained in step S4 into powder to obtain the zirconia composite powder. Sodium polymethacrylate is used as a dispersant, and polyvinyl alcohol is used as a binder. The Tg of the binder used is 90°C.

[0253] The preparation of the stabilized zirconium oxide powder in step S1 includes the following steps: A1, dissolving zirconium nitrate in water to obtain an aqueous solution of zirconium nitrate; A2, adding a stabilizer to the aqueous solution system of step A1 to form stabilized zirconium oxide; A3, drying the mixture obtained in step A2 into powder; A4, sintering the powder obtained in step A3; A5, grinding and dispersing the product obtained in step A4 to obtain the stabilized zirconium oxide powder.

[0254] Wherein, in step A1, the mass ratio of zirconium nitrate to water is 1:4, the ambient temperature is 35° C., the stirring rate is 32 Hz, and the reaction time is 4.5 h.

[0255] Wherein, in step A2, the mass ratio of the stabilizer to zirconium nitrate is 0.06:1.

[0256] Wherein, in step A3, the drying equipment is any one of an oven, a microwave dryer, and a spray dryer, the drying temperature is 210° C., and the drying time is 5 hours.

[0257] Among them, in the step A4, the sintering equipment is a rotary kiln, the sintering temperature is 1110° C., the heating time is 3.5 hours, the temperature is kept at 1110° C. for 3 hours, and the cooling time is 3 hours.

[0258] Wherein, in the step A5, the mesh number of the ground stabilized zirconia powder is 290 mesh, and the particle size of the stabilized zirconia powder obtained by granulation is 50 μm.

[0259] The D50 of the stabilized zirconia is 0.24 μm and the D90 is 0.50 μm; the stabilized zirconia contains 0.4% monoclinic phase and 98.9% tetragonal phase; the specific surface area of ​​the stabilized zirconia is 10.5 m 2 / g.

[0260] Wherein, in step S2, the diluent is pure water.

[0261] Wherein, in step S2, the mass ratio of the diluent to the dispersant is 6:1, and the mass ratio of the diluent to the binder is 6:1.

[0262] Wherein, in the step S3, the mass ratio of the stabilized zirconia powder, water and the diluted dispersant is 100:300:7, the temperature of the mixture is controlled at 25°C, the mixing rate is 10-50Hz, and the mixing time is 5.5h.

[0263] Wherein, a dispersant is used to adjust the pH value of the solution system in step S3 to 8.0.

[0264] Wherein, in step S4, the mass ratio of the stabilized zirconia powder, water, diluted dispersant and diluted binder is 100:300:7:4.3, the temperature of the mixture is controlled at 25°C, the mixing rate is 32Hz, and the mixing time is 2h.

[0265] Wherein, in step S5, the drying temperature is 205° C. and the drying time is 6 hours.

[0266] Wherein, in the step S5, drying is performed by high-speed centrifugal spraying.

[0267] Example 10

[0268] The present embodiment provides a method for preparing a zirconia composite powder, comprising the following steps: S1, providing stabilized zirconia powder, a dispersant and a binder; S2, diluting the dispersant and the binder with a diluent; S3, mixing the stabilized zirconia powder, water and the diluted dispersant; S4, adding the diluted binder to the mixture obtained in step S3; S5, drying the mixture obtained in step S4 into powder to obtain the zirconia composite powder. Propylene glycol methyl ether is used as a dispersant, and carboxymethyl cellulose is used as a binder. The Tg of the binder used is 71°C.

[0269] The preparation of the stabilized zirconium oxide powder in step S1 includes the following steps: A1, dissolving zirconium nitrate in water to obtain an aqueous solution of zirconium nitrate; A2, adding a stabilizer to the aqueous solution system of step A1 to form stabilized zirconium oxide; A3, drying the mixture obtained in step A2 into powder; A4, sintering the powder obtained in step A3; A5, grinding and dispersing the product obtained in step A4 to obtain the stabilized zirconium oxide powder.

[0270] Wherein, in step A1, the mass ratio of zirconium nitrate to water is 1:5, the ambient temperature is 35° C., the stirring rate is 35 Hz, and the reaction time is 4.5 h.

[0271] Wherein, in step A2, the mass ratio of the stabilizer to zirconium nitrate is 0.07:1.

[0272] Wherein, in step A3, the drying equipment is any one of an oven, a microwave dryer, and a spray dryer, the drying temperature is 220° C., and the drying time is 6 hours.

[0273] Among them, in the step A4, the sintering equipment is a rotary kiln, the sintering temperature is 1110° C., the heating time is 4.5 hours, the temperature is kept at 1110° C. for 3 hours, and the cooling time is 4 hours.

[0274] Wherein, in the step A5, the mesh number of the ground stabilized zirconia powder is 270 mesh, and the particle size of the stabilized zirconia powder obtained by granulation is 55 μm.

[0275] The D50 of the stabilized zirconia is 0.3 μm and the D90 is 0.50 μm; the stabilized zirconia contains 0.4% monoclinic phase and 99% tetragonal phase; the specific surface area of ​​the stabilized zirconia is 10.5 m 2 / g.

[0276] Wherein, in step S2, the diluent is pure water.

[0277] Wherein, in step S2, the mass ratio of the diluent to the dispersant is 7:1, and the mass ratio of the diluent to the binder is 6:1.

[0278] Wherein, in the step S3, the mass ratio of the stabilized zirconia powder, water and the diluted dispersant is 100:300:7, the temperature of the mixture is controlled at 25°C, the mixing rate is 10-50Hz, and the mixing time is 6h.

[0279] Wherein, a dispersant is used to adjust the pH value of the solution system in step S3 to 8.0.

[0280] Wherein, in step S4, the mass ratio of the stabilized zirconia powder, water, diluted dispersant and diluted binder is 100:300:7:4.5, the temperature of the mixture is controlled at 25°C, the mixing rate is 35Hz, and the mixing time is 2h.

[0281] Wherein, in step S5, the drying temperature is 205° C. and the drying time is 6 hours.

[0282] Wherein, in the step S5, drying is performed by high-speed centrifugal spraying.

[0283] Embodiment 11

[0284] The present embodiment provides a method for preparing a zirconia composite powder, comprising the following steps: S1, providing stabilized zirconia powder, a dispersant and a binder; S2, diluting the dispersant and the binder with a diluent; S3, mixing the stabilized zirconia powder, water and the diluted dispersant; S4, adding the diluted binder to the mixture obtained in step S3; S5, drying the mixture obtained in step S4 into powder to obtain the zirconia composite powder. Propylene glycol methyl ether is used as a dispersant, and carboxymethyl cellulose is used as a binder. The Tg of the binder used is 80°C.

[0285] The preparation of the stabilized zirconium oxide powder in step S1 includes the following steps: A1, dissolving zirconium nitrate in water to obtain an aqueous solution of zirconium nitrate; A2, adding a stabilizer to the aqueous solution system of step A1 to form stabilized zirconium oxide; A3, drying the mixture obtained in step A2 into powder; A4, sintering the powder obtained in step A3; A5, grinding and dispersing the product obtained in step A4 to obtain the stabilized zirconium oxide powder.

[0286] Wherein, in step A1, the mass ratio of zirconium nitrate to water is 1:5.3, the ambient temperature is 38° C., the stirring rate is 35 Hz, and the reaction time is 5.5 h.

[0287] Wherein, in step A2, the mass ratio of the stabilizer to zirconium nitrate is 0.08:1.

[0288] Wherein, in step A3, the drying equipment is any one of an oven, a microwave dryer, and a spray dryer, the drying temperature is 225° C., and the drying time is 7 hours.

[0289] Wherein, in step A4, the sintering equipment is a rotary kiln, the sintering temperature is 1110° C., the heating time is 5 hours, the temperature is kept at 1110° C. for 3 hours, and the cooling time is 4.5 hours.

[0290] Wherein, in the step A5, the mesh size of the ground stabilized zirconia powder is 250 mesh, and the particle size of the stabilized zirconia powder obtained by granulation is 62 μm.

[0291] The D50 of the stabilized zirconia is 0.38 μm and the D90 is 0.56 μm; the stabilized zirconia contains 0.4% monoclinic phase and 99% tetragonal phase; the specific surface area of ​​the stabilized zirconia is 10.3 m 2 / g.

[0292] Wherein, in step S2, the diluent is pure water.

[0293] Wherein, in step S2, the mass ratio of the diluent to the dispersant is 8.5:1, and the mass ratio of the diluent to the binder is 6.5:1.

[0294] Wherein, in the step S3, the mass ratio of the stabilized zirconium oxide powder, water and diluted dispersant is 100:300:7.5, the temperature of the mixture is controlled at 25°C, the mixing rate is 10-50Hz, and the mixing time is 7h.

[0295] Wherein, a dispersant is used to adjust the pH value of the solution system in step S3 to 8.2.

[0296] Wherein, in step S4, the mass ratio of the stabilized zirconia powder, water, diluted dispersant and diluted binder is 100:300:7.5:8, the temperature of the mixture is controlled at 25°C, the mixing rate is 35Hz, and the mixing time is 2.5h.

[0297] Wherein, in step S5, the drying temperature is 205° C. and the drying time is 6 hours.

[0298] Wherein, in the step S5, drying is performed by high-speed centrifugal spraying.

[0299] Example 12

[0300] The present embodiment provides a method for preparing a zirconia composite powder, comprising the following steps: S1, providing stabilized zirconia powder, a dispersant and a binder; S2, diluting the dispersant and the binder with a diluent; S3, mixing the stabilized zirconia powder, water and the diluted dispersant; S4, adding the diluted binder to the mixture obtained in step S3; S5, drying the mixture obtained in step S4 into powder to obtain the zirconia composite powder. Sodium oleate is used as a dispersant, and carboxymethyl cellulose is used as a binder. The Tg of the binder used is 71°C.

[0301] The preparation of the stabilized zirconium oxide powder in step S1 includes the following steps: A1, dissolving zirconium nitrate in water to obtain an aqueous solution of zirconium nitrate; A2, adding a stabilizer to the aqueous solution system of step A1 to form stabilized zirconium oxide; A3, drying the mixture obtained in step A2 into powder; A4, sintering the powder obtained in step A3; A5, grinding and dispersing the product obtained in step A4 to obtain the stabilized zirconium oxide powder.

[0302] Wherein, in step A1, the mass ratio of zirconium nitrate to water is 1:5.6, the ambient temperature is 40° C., the stirring rate is 35 Hz, and the reaction time is 6 h.

[0303] Wherein, in step A2, the mass ratio of the stabilizer to zirconium nitrate is 0.09:1.

[0304] Wherein, in step A3, the drying equipment is any one of an oven, a microwave dryer, and a spray dryer, the drying temperature is 230° C., and the drying time is 8 hours.

[0305] Among them, in step A4, the sintering equipment is a rotary kiln, the sintering temperature is 1110° C., the heating time is 5.5 hours, the temperature is kept at 1110° C. for 3.5 hours, and the cooling time is 5 hours.

[0306] Wherein, in the step A5, the mesh number of the ground stabilized zirconia powder is 230 mesh, and the particle size of the stabilized zirconia powder obtained by granulation is 64 μm.

[0307] The D50 of the stabilized zirconia is 0.4 μm and the D90 is 0.58 μm; the stabilized zirconia contains 0.4% monoclinic phase and 99% tetragonal phase; the specific surface area of ​​the stabilized zirconia is 10.3 m 2 / g.

[0308] Wherein, in step S2, the diluent is pure water.

[0309] Wherein, in step S2, the mass ratio of the diluent to the dispersant is 9:1, and the mass ratio of the diluent to the binder is 6.5:1.

[0310] Wherein, in the step S3, the mass ratio of the stabilized zirconia powder, water and the diluted dispersant is 100:300:8.0, the temperature of the mixture is controlled at 25°C, the mixing rate is 10-50Hz, and the mixing time is 7.5h.

[0311] Wherein, a dispersant is used to adjust the pH value of the solution system in step S3 to 8.4.

[0312] Wherein, in step S4, the mass ratio of the stabilized zirconia powder, water, diluted dispersant and diluted binder is 100:300:8:8, the temperature of the mixture is controlled at 25°C, the mixing rate is 35Hz, and the mixing time is 3h.

[0313] Wherein, in step S5, the drying temperature is 215° C. and the drying time is 7 hours.

[0314] Wherein, in the step S5, drying is performed by high-speed centrifugal spraying.

[0315] Example 13

[0316] This embodiment provides a method for preparing a zirconia composite powder, comprising the following steps: S1, providing stabilized zirconia powder, a dispersant and a binder; S2, diluting the dispersant and the binder with a diluent; S3, mixing the stabilized zirconia powder, water and the diluted dispersant; S4, adding the diluted binder to the mixture obtained in step S3; S5, drying the mixture obtained in step S4 into powder to obtain the zirconia composite powder. Sodium oleate is used as a dispersant, and polymethyl methacrylate is used as a binder. The Tg of the binder used is 80°C.

[0317] The preparation of the stabilized zirconium oxide powder in step S1 includes the following steps: A1, dissolving zirconium nitrate in water to obtain an aqueous solution of zirconium nitrate; A2, adding a stabilizer to the aqueous solution system of step A1 to form stabilized zirconium oxide; A3, drying the mixture obtained in step A2 into powder; A4, sintering the powder obtained in step A3; A5, grinding and dispersing the product obtained in step A4 to obtain the stabilized zirconium oxide powder.

[0318] Wherein, in step A1, the mass ratio of zirconium nitrate to water is 1:5.8, the ambient temperature is 40° C., the stirring rate is 40 Hz, and the reaction time is 7 hours.

[0319] Wherein, in step A2, the mass ratio of the stabilizer to zirconium nitrate is 0.09:1.

[0320] Wherein, in step A3, the drying equipment is any one of an oven, a microwave dryer, and a spray dryer, the drying temperature is 230° C., and the drying time is 8 hours.

[0321] Among them, in the step A4, the sintering equipment is a rotary kiln, the sintering temperature is 1120° C., the heating time is 5.5 hours, the temperature is kept at 1120° C. for 3.5 hours, and the cooling time is 5 hours.

[0322] Wherein, in the step A5, the mesh size of the ground stabilized zirconia powder is 200 mesh, and the particle size of the stabilized zirconia powder obtained by granulation is 64 μm.

[0323] The D50 of the stabilized zirconia is 0.4 μm and the D90 is 0.58 μm; the stabilized zirconia contains 0.4% monoclinic phase and 99% tetragonal phase; the specific surface area of ​​the stabilized zirconia is 10.3 m 2 / g.

[0324] Wherein, in step S2, the diluent is pure water.

[0325] Wherein, in step S2, the mass ratio of the diluent to the dispersant is 9.5:1, and the mass ratio of the diluent to the binder is 7.0:1.

[0326] Wherein, in the step S3, the mass ratio of the stabilized zirconia powder, water and the diluted dispersant is 100:300:8.2, the temperature of the mixture is controlled at 25°C, the mixing rate is 10-50Hz, and the mixing time is 7.8h.

[0327] Wherein, a dispersant is used to adjust the pH value of the solution system in step S3 to 8.5.

[0328] Wherein, in step S4, the mass ratio of the stabilized zirconia powder, water, diluted dispersant and diluted binder is 100:300:8.2:8.5, the temperature of the mixture is controlled at 25°C, the mixing rate is 35Hz, and the mixing time is 4h.

[0329] Wherein, in step S5, the drying temperature is 220° C. and the drying time is 8 hours.

[0330] Wherein, in the step S5, drying is performed by high-speed centrifugal spraying.

[0331] Embodiment 14

[0332] The present embodiment provides a method for preparing a zirconia composite powder, comprising the following steps: S1, providing stabilized zirconia powder, a dispersant and a binder; S2, diluting the dispersant and the binder with a diluent; S3, mixing the stabilized zirconia powder, water and the diluted dispersant; S4, adding the diluted binder to the mixture obtained in step S3; S5, drying the mixture obtained in step S4 into powder to obtain the zirconia composite powder. Sodium hexametaphosphate is used as a dispersant, and polymethyl methacrylate is used as a binder. The Tg of the binder used is 71°C.

[0333] The preparation of the stabilized zirconium oxide powder in step S1 includes the following steps: A1, dissolving zirconium nitrate in water to obtain an aqueous solution of zirconium nitrate; A2, adding a stabilizer to the aqueous solution system of step A1 to form stabilized zirconium oxide; A3, drying the mixture obtained in step A2 into powder; A4, sintering the powder obtained in step A3; A5, grinding and dispersing the product obtained in step A4 to obtain the stabilized zirconium oxide powder.

[0334] Wherein, in step A1, the mass ratio of zirconium nitrate to water is 1:5.8, the ambient temperature is 40° C., the stirring rate is 40 Hz, and the reaction time is 7.5 h.

[0335] Wherein, in step A2, the mass ratio of the stabilizer to zirconium nitrate is 0.10:1.

[0336] Wherein, in step A3, the drying equipment is any one of an oven, a microwave dryer, and a spray dryer, the drying temperature is 230° C., and the drying time is 9 hours.

[0337] Among them, in the step A4, the sintering equipment is a rotary kiln, the sintering temperature is 1120° C., the heating time is 5.5 hours, the temperature is kept at 1120° C. for 3.5 hours, and the cooling time is 5 hours.

[0338] Wherein, in the step A5, the mesh size of the ground stabilized zirconia powder is 180 mesh, and the particle size of the stabilized zirconia powder obtained by granulation is 64 μm.

[0339] The D50 of the stabilized zirconia is 0.4 μm and the D90 is 0.58 μm; the stabilized zirconia contains 0.4% monoclinic phase and 99% tetragonal phase; the specific surface area of ​​the stabilized zirconia is 10.3 m 2 / g.

[0340] Wherein, in step S2, the diluent is pure water.

[0341] Wherein, in step S2, the mass ratio of the diluent to the dispersant is 9.5:1, and the mass ratio of the diluent to the binder is 7.0:1.

[0342] Wherein, in the step S3, the mass ratio of the stabilized zirconia powder, water and the diluted dispersant is 100:300:8.2, the temperature of the mixture is controlled at 25°C, the mixing rate is 10-50Hz, and the mixing time is 7.8h.

[0343] Wherein, a dispersant is used to adjust the pH value of the solution system in step S3 to 8.5.

[0344] Wherein, in step S4, the mass ratio of the stabilized zirconia powder, water, diluted dispersant and diluted binder is 100:300:8.2:8.5, the temperature of the mixture is controlled at 25°C, the mixing rate is 35Hz, and the mixing time is 4h.

[0345] Wherein, in step S5, the drying temperature is 220° C. and the drying time is 8 hours.

[0346] Wherein, in the step S5, drying is performed by high-speed centrifugal spraying.

[0347] Embodiment 15

[0348] This embodiment provides a method for preparing a zirconia composite powder, comprising the following steps: S1, providing stabilized zirconia powder, a dispersant and a binder; S2, diluting the dispersant and the binder with a diluent; S3, mixing the stabilized zirconia powder, water and the diluted dispersant; S4, adding the diluted binder to the mixture obtained in step S3; S5, drying the mixture obtained in step S4 into powder to obtain the zirconia composite powder. Sodium hexametaphosphate is used as a dispersant, and sodium alginate is used as a binder. The Tg of the binder used is 80°C.

[0349] The preparation of the stabilized zirconium oxide powder in step S1 includes the following steps: A1, dissolving zirconium nitrate in water to obtain an aqueous solution of zirconium nitrate; A2, adding a stabilizer to the aqueous solution system of step A1 to form stabilized zirconium oxide; A3, drying the mixture obtained in step A2 into powder; A4, sintering the powder obtained in step A3; A5, grinding and dispersing the product obtained in step A4 to obtain the stabilized zirconium oxide powder.

[0350] Wherein, in step A1, the mass ratio of zirconium nitrate to water is 1:5.8, the ambient temperature is 42° C., the stirring rate is 40 Hz, and the reaction time is 8 h.

[0351] Wherein, in step A2, the mass ratio of the stabilizer to zirconium nitrate is 0.11:1.

[0352] Wherein, in step A3, the drying equipment is any one of an oven, a microwave dryer, and a spray dryer, the drying temperature is 230° C., and the drying time is 10 hours.

[0353] Wherein, in step A4, the sintering equipment is a rotary kiln, the sintering temperature is 1130° C., the heating time is 6 hours, the temperature is kept at 1130° C. for 4 hours, and the cooling time is 6 hours.

[0354] Wherein, in the step A5, the mesh size of the ground stabilized zirconia powder is 150 mesh, and the particle size of the stabilized zirconia powder obtained by granulation is 63 μm.

[0355] The D50 of the stabilized zirconia is 0.41 μm and the D90 is 0.62 μm; the stabilized zirconia contains 0.5% monoclinic phase and 99% tetragonal phase; the specific surface area of ​​the stabilized zirconia is 10.2 m 2 / g.

[0356] Wherein, in step S2, the diluent is pure water.

[0357] Wherein, in step S2, the mass ratio of the diluent to the dispersant is 10:1, and the mass ratio of the diluent to the binder is 7.0:1.

[0358] Wherein, in the step S3, the mass ratio of the stabilized zirconium oxide powder, water and diluted dispersant is 100:300:8.5, the temperature of the mixture is controlled at 25°C, the mixing rate is 10-50Hz, and the mixing time is 8h.

[0359] Wherein, a dispersant is used to adjust the pH value of the solution system in step S3 to 8.5.

[0360] Wherein, in step S4, the mass ratio of the stabilized zirconia powder, water, diluted dispersant and diluted binder is 100:300:8.5:8.5, the temperature of the mixture is controlled at 25°C, the mixing rate is 40Hz, and the mixing time is 5h.

[0361] Wherein, in step S5, the drying temperature is 225° C. and the drying time is 8 hours.

[0362] Wherein, in the step S5, drying is performed by high-speed centrifugal spraying.

[0363] Example 16

[0364] The present embodiment provides a method for preparing a zirconia composite powder, comprising the following steps: S1, providing stabilized zirconia powder, a dispersant and a binder; S2, diluting the dispersant and the binder with a diluent; S3, mixing the stabilized zirconia powder, water and the diluted dispersant; S4, adding the diluted binder to the mixture obtained in step S3; S5, drying the mixture obtained in step S4 into powder to obtain the zirconia composite powder. Sodium tripolyphosphate is used as a dispersant, and polymethyl methacrylate is used as a binder. The Tg of the binder used is 71°C.

[0365] The preparation of the stabilized zirconium oxide powder in step S1 includes the following steps: A1, dissolving zirconium nitrate in water to obtain an aqueous solution of zirconium nitrate; A2, adding a stabilizer to the aqueous solution system of step A1 to form stabilized zirconium oxide; A3, drying the mixture obtained in step A2 into powder; A4, sintering the powder obtained in step A3; A5, grinding and dispersing the product obtained in step A4 to obtain the stabilized zirconium oxide powder.

[0366] Wherein, in step A1, the mass ratio of zirconium nitrate to water is 1:6.3, the ambient temperature is 45° C., the stirring rate is 40 Hz, and the reaction time is 8.5 h.

[0367] Wherein, in step A2, the mass ratio of the stabilizer to zirconium nitrate is 0.13:1.

[0368] Wherein, in step A3, the drying equipment is any one of an oven, a microwave dryer, and a spray dryer, the drying temperature is 240° C., and the drying time is 12 hours.

[0369] Wherein, in step A4, the sintering equipment is a rotary kiln, the sintering temperature is 1135° C., the heating time is 6 hours, the temperature is kept at 1135° C. for 4 hours, and the cooling time is 8 hours.

[0370] Wherein, in the step A5, the mesh size of the ground stabilized zirconia powder is 120 mesh, and the particle size of the stabilized zirconia powder obtained by granulation is 65 μm.

[0371] The D50 of the stabilized zirconia is 0.44 μm and the D90 is 0.70 μm; the stabilized zirconia contains 0.5% monoclinic phase and 99.3% tetragonal phase; the specific surface area of ​​the stabilized zirconia is 10.1 m 2 / g.

[0372] Wherein, in step S2, the diluent is pure water.

[0373] Wherein, in step S2, the mass ratio of the diluent to the dispersant is 12:1, and the mass ratio of the diluent to the binder is 7.5:1.

[0374] Wherein, in the step S3, the mass ratio of the stabilized zirconia powder, water and the diluted dispersant is 100:300:9, the temperature of the mixture is controlled at 25°C, the mixing rate is 10-50Hz, and the mixing time is 8h.

[0375] Wherein, a dispersant is used to adjust the pH value of the solution system in step S3 to 8.6.

[0376] Wherein, in step S4, the mass ratio of the stabilized zirconia powder, water, diluted dispersant and diluted binder is 100:300:9:10, the temperature of the mixture is controlled at 25°C, the mixing rate is 40Hz, and the mixing time is 6h.

[0377] Wherein, in step S5, the drying temperature is 225° C. and the drying time is 10 hours.

[0378] Wherein, in the step S5, drying is performed by high-speed centrifugal spraying.

[0379] Embodiment 17

[0380] This embodiment provides a method for preparing a zirconia composite powder, comprising the following steps: S1, providing stabilized zirconia powder, a dispersant and a binder; S2, diluting the dispersant and the binder with a diluent; S3, mixing the stabilized zirconia powder, water and the diluted dispersant; S4, adding the diluted binder to the mixture obtained in step S3; S5, drying the mixture obtained in step S4 into powder to obtain the zirconia composite powder. Sodium tripolyphosphate is used as a dispersant, and polyethylene oxide is used as a binder. The Tg of the binder used is 80°C.

[0381] The preparation of the stabilized zirconium oxide powder in step S1 includes the following steps: A1, dissolving zirconium nitrate in water to obtain an aqueous solution of zirconium nitrate; A2, adding a stabilizer to the aqueous solution system of step A1 to form stabilized zirconium oxide; A3, drying the mixture obtained in step A2 into powder; A4, sintering the powder obtained in step A3; A5, grinding and dispersing the product obtained in step A4 to obtain the stabilized zirconium oxide powder.

[0382] Wherein, in step A1, the mass ratio of zirconium nitrate to water is 1:6.5, the ambient temperature is 50° C., the stirring rate is 45 Hz, and the reaction time is 9 hours.

[0383] Wherein, in step A2, the mass ratio of the stabilizer to zirconium nitrate is 0.14:1.

[0384] Wherein, in step A3, the drying equipment is any one of an oven, a microwave dryer, and a spray dryer, the drying temperature is 240° C., and the drying time is 12 hours.

[0385] Wherein, in step A4, the sintering equipment is a rotary kiln, the sintering temperature is 1135° C., the heating time is 6 hours, the temperature is kept at 1135° C. for 4 hours, and the cooling time is 8 hours.

[0386] Wherein, in the step A5, the mesh size of the ground stabilized zirconia powder is 120 mesh, and the particle size of the stabilized zirconia powder obtained by granulation is 65 μm.

[0387] The D50 of the stabilized zirconia is 0.44 μm and the D90 is 0.70 μm; the stabilized zirconia contains 0.5% monoclinic phase and 99.3% tetragonal phase; the specific surface area of ​​the stabilized zirconia is 10.1 m 2 / g.

[0388] Wherein, in step S2, the diluent is pure water.

[0389] Wherein, in step S2, the mass ratio of the diluent to the dispersant is 12:1, and the mass ratio of the diluent to the binder is 7.5:1.

[0390] Wherein, in the step S3, the mass ratio of the stabilized zirconium oxide powder, water and diluted dispersant is 100:300:9.5, the temperature of the mixture is controlled at 25°C, the mixing rate is 10-50Hz, and the mixing time is 8h.

[0391] Wherein, a dispersant is used to adjust the pH value of the solution system in step S3 to 8.6.

[0392] Wherein, in step S4, the mass ratio of the stabilized zirconia powder, water, diluted dispersant and diluted binder is 100:300:9.5:10, the temperature of the mixture is controlled at 25°C, the mixing rate is 40Hz, and the mixing time is 7h.

[0393] Wherein, in step S5, the drying temperature is 225° C. and the drying time is 10 hours.

[0394] Wherein, in the step S5, drying is performed by high-speed centrifugal spraying.

[0395] Embodiment 18

[0396] This embodiment provides a method for preparing a zirconia composite powder, comprising the following steps: S1, providing stabilized zirconia powder, a dispersant and a binder; S2, diluting the dispersant and the binder with a diluent; S3, mixing the stabilized zirconia powder, water and the diluted dispersant; S4, adding the diluted binder to the mixture obtained in step S3; S5, drying the mixture obtained in step S4 into powder to obtain the zirconia composite powder. Fatty alcohol polyvinyl ether is used as a dispersant, and polyethylene oxide is used as a binder. The Tg of the binder used is 80°C.

[0397] The preparation of the stabilized zirconium oxide powder in step S1 includes the following steps: A1, dissolving zirconium nitrate in water to obtain an aqueous solution of zirconium nitrate; A2, adding a stabilizer to the aqueous solution system of step A1 to form stabilized zirconium oxide; A3, drying the mixture obtained in step A2 into powder; A4, sintering the powder obtained in step A3; A5, grinding and dispersing the product obtained in step A4 to obtain the stabilized zirconium oxide powder.

[0398] Wherein, in step A1, the mass ratio of zirconium nitrate to water is 1:7, the ambient temperature is 50° C., the stirring rate is 50 Hz, and the reaction time is 10 h.

[0399] Wherein, in step A2, the mass ratio of the stabilizer to zirconium nitrate is 0.15:1.

[0400] Wherein, in step A3, the drying equipment is any one of an oven, a microwave dryer, and a spray dryer, the drying temperature is 240° C., and the drying time is 12 hours.

[0401] Wherein, in step A4, the sintering equipment is a rotary kiln, the sintering temperature is 1135° C., the heating time is 6 hours, the temperature is kept at 1135° C. for 4 hours, and the cooling time is 8 hours.

[0402] Wherein, in the step A5, the mesh size of the ground stabilized zirconia powder is 120 mesh, and the particle size of the stabilized zirconia powder obtained by granulation is 65 μm.

[0403] The D50 of the stabilized zirconia is 0.44 μm and the D90 is 0.70 μm; the stabilized zirconia contains 0.5% monoclinic phase and 99.3% tetragonal phase; the specific surface area of ​​the stabilized zirconia is 10.1 m 2 / g.

[0404] Wherein, in step S2, the diluent is pure water.

[0405] Wherein, in step S2, the mass ratio of the diluent to the dispersant is 15:1, and the mass ratio of the diluent to the binder is 8.5:1.

[0406] Wherein, in the step S3, the mass ratio of the stabilized zirconia powder, water and the diluted dispersant is 100:300:10, the temperature of the mixture is controlled at 25°C, the mixing rate is 10-50Hz, and the mixing time is 9h.

[0407] Wherein, a dispersant is used to adjust the pH value of the solution system in step S3 to 9.

[0408] Wherein, in step S4, the mass ratio of the stabilized zirconia powder, water, diluted dispersant and diluted binder is 100:300:10:10, the temperature of the mixture is controlled at 25°C, the mixing rate is 50 Hz, and the mixing time is 10 hours.

[0409] Wherein, in step S5, the drying temperature is 270° C. and the drying time is 15 hours.

[0410] Wherein, in the step S5, drying is performed by high-speed centrifugal spraying.

[0411] Embodiment 19

[0412] This embodiment provides a method for preparing a zirconia composite powder, comprising the following steps: S1, providing stabilized zirconia powder, a dispersant and a binder; S2, diluting the dispersant and the binder with a diluent; S3, mixing the stabilized zirconia powder, water and the diluted dispersant; S4, adding the diluted binder to the mixture obtained in step S3; S5, drying the mixture obtained in step S4 into powder to obtain the zirconia composite powder. Fatty alcohol polyvinyl ether is used as a dispersant, and polyethylene oxide is used as a binder. The Tg of the binder used is 80°C.

[0413] The preparation of the stabilized zirconium oxide powder in step S1 includes the following steps: A1, dissolving zirconium nitrate in water to obtain an aqueous solution of zirconium nitrate; A2, adding a stabilizer to the aqueous solution system of step A1 to form stabilized zirconium oxide; A3, drying the mixture obtained in step A2 into powder; A4, sintering the powder obtained in step A3; A5, grinding and dispersing the product obtained in step A4 to obtain the stabilized zirconium oxide powder.

[0414] Wherein, in step A1, the mass ratio of zirconium nitrate to water is 1:7, the ambient temperature is 50° C., the stirring rate is 50 Hz, and the reaction time is 10 h.

[0415] Wherein, in step A2, the mass ratio of the stabilizer to zirconium nitrate is 0.16:1.

[0416] Wherein, in step A3, the drying equipment is any one of an oven, a microwave dryer, and a spray dryer, the drying temperature is 270° C., and the drying time is 17 hours.

[0417] Wherein, in step A4, the sintering equipment is a rotary kiln, the sintering temperature is 1150° C., the heating time is 6 hours, the temperature is kept at 1150° C. for 4 hours, and the cooling time is 8 hours.

[0418] Wherein, in the step A5, the mesh size of the ground stabilized zirconia powder is 100 mesh, and the particle size of the stabilized zirconia powder obtained by granulation is 70 μm.

[0419] The D50 of the stabilized zirconia is 0.46 μm and the D90 is 0.90 μm; the stabilized zirconia contains 0.5% monoclinic phase and 99.3% tetragonal phase; the specific surface area of ​​the stabilized zirconia is 10.3 m 2 / g.

[0420] Wherein, in step S2, the diluent is pure water.

[0421] Wherein, in step S2, the mass ratio of the diluent to the dispersant is 18:1, and the mass ratio of the diluent to the binder is 9.5:1.

[0422] Wherein, in the step S3, the mass ratio of the stabilized zirconium oxide powder, water and the diluted dispersant is 100:300:10, the temperature of the mixture is controlled at 25°C, the mixing rate is 10-50Hz, and the mixing time is 10h.

[0423] Wherein, a dispersant is used to adjust the pH value of the solution system in step S3 to 9.

[0424] Wherein, in step S4, the mass ratio of the stabilized zirconia powder, water, diluted dispersant and diluted binder is 100:300:10:10, the temperature of the mixture is controlled at 28°C, the mixing rate is 50Hz, and the mixing time is 10h.

[0425] Wherein, in step S5, the drying temperature is 270° C. and the drying time is 18 hours.

[0426] Wherein, in the step S5, drying is performed by high-speed centrifugal spraying.

[0427] Embodiment 20

[0428] This embodiment provides a method for preparing a zirconia composite powder, comprising the following steps: S1, providing stabilized zirconia powder, a dispersant and a binder; S2, diluting the dispersant and the binder with a diluent; S3, mixing the stabilized zirconia powder, water and the diluted dispersant; S4, adding the diluted binder to the mixture obtained in step S3; S5, drying the mixture obtained in step S4 into powder to obtain the zirconia composite powder. Fatty alcohol polyvinyl ether is used as a dispersant, and polyethylene oxide is used as a binder. The Tg of the binder used is 71°C.

[0429] The preparation of the stabilized zirconium oxide powder in step S1 includes the following steps: A1, dissolving zirconium nitrate in water to obtain an aqueous solution of zirconium nitrate; A2, adding a stabilizer to the aqueous solution system of step A1 to form stabilized zirconium oxide; A3, drying the mixture obtained in step A2 into powder; A4, sintering the powder obtained in step A3; A5, grinding and dispersing the product obtained in step A4 to obtain the stabilized zirconium oxide powder.

[0430] Wherein, in step A1, the mass ratio of zirconium nitrate to water is 1:7, the ambient temperature is 50° C., the stirring rate is 50 Hz, and the reaction time is 10 h.

[0431] Wherein, in step A2, the mass ratio of the stabilizer to zirconium nitrate is 0.16:1.

[0432] Wherein, in step A3, the drying equipment is any one of an oven, a microwave dryer, and a spray dryer, the drying temperature is 270° C., and the drying time is 20 hours.

[0433] Wherein, in step A4, the sintering equipment is a rotary kiln, the sintering temperature is 1200° C., the heating time is 10 hours, the temperature is kept at 1200° C. for 4 hours, and the cooling time is 10 hours.

[0434] Wherein, in the step A5, the mesh size of the ground stabilized zirconia powder is 100 mesh, and the particle size of the stabilized zirconia powder obtained by granulation is 75 μm.

[0435] The D50 of the stabilized zirconia is 0.5 μm and the D90 is 1.0 μm; the stabilized zirconia contains 0.5% monoclinic phase and 99.5% tetragonal phase; the specific surface area of ​​the stabilized zirconia is 10 m 2 / g.

[0436] Wherein, in step S2, the diluent is pure water.

[0437] Wherein, in step S2, the mass ratio of the diluent to the dispersant is 20:1, and the mass ratio of the diluent to the binder is 10:1.

[0438] Wherein, in the step S3, the mass ratio of the stabilized zirconium oxide powder, water and the diluted dispersant is 120:300:10, the temperature of the mixture is controlled at 25°C, the mixing rate is 10-50Hz, and the mixing time is 10h.

[0439] Wherein, a dispersant is used to adjust the pH value of the solution system in step S3 to 9.

[0440] Wherein, in step S4, the mass ratio of the stabilized zirconia powder, water, diluted dispersant and diluted binder is 120:300:10:10, the temperature of the mixture is controlled at 30°C, the mixing rate is 50 Hz, and the mixing time is 10 hours.

[0441] Wherein, in step S5, the drying temperature is 270° C. and the drying time is 20 h.

[0442] Wherein, in the step S5, drying is performed by high-speed centrifugal spraying.

[0443] Comparative Example 1

[0444] This comparative example provides a method for preparing a zirconia composite powder, comprising the following steps: S1, providing stabilized zirconia powder, a dispersant and a binder; S2, diluting the dispersant and the binder with a diluent; S3, mixing the stabilized zirconia powder, water and the diluted dispersant; S4, adding the diluted binder to the mixture obtained in step S3; S5, drying the mixture obtained in step S4 into powder to obtain the zirconia composite powder. No dispersant is added, and polyvinyl alcohol is used as a binder. The Tg of the binder used is 85°C.

[0445] The preparation of the stabilized zirconium oxide powder in step S1 includes the following steps: A1, dissolving zirconium nitrate in water to obtain an aqueous solution of zirconium nitrate; A2, adding a stabilizer to the aqueous solution system of step A1 to form stabilized zirconium oxide; A3, drying the mixture obtained in step A2 into powder; A4, sintering the powder obtained in step A3; A5, grinding and dispersing the product obtained in step A4 to obtain the stabilized zirconium oxide powder.

[0446] Wherein, in step A1, the mass ratio of zirconium nitrate to water is 1:0.5, the ambient temperature is 50° C., the stirring rate is 50 Hz, and the reaction time is 10 h.

[0447] Wherein, in step A2, the mass ratio of the stabilizer to zirconium nitrate is 0.16:1.

[0448] Wherein, in step A3, the drying equipment is any one of an oven, a microwave dryer, and a spray dryer, the drying temperature is 280° C., and the drying time is 20 hours.

[0449] Wherein, in step A4, the sintering equipment is a rotary kiln, the sintering temperature is 1200° C., the heating time is 10 hours, the temperature is kept at 1200° C. for 4 hours, and the cooling time is 10 hours.

[0450] Wherein, in the step A5, the mesh size of the ground stabilized zirconia powder is 80 mesh, and the particle size of the stabilized zirconia powder obtained by granulation is 90 μm.

[0451] The D50 of the stabilized zirconia is 0.8 μm and the D90 is 1.2 μm; the stabilized zirconia contains 0.5% monoclinic phase and 99.5% tetragonal phase; the specific surface area of ​​the stabilized zirconia is 10 m 2 / g.

[0452] Wherein, in step S2, the diluent is pure water.

[0453] Wherein, in step S2, the mass ratio of the diluent to the dispersant is 0.4:0, and the mass ratio of the diluent to the binder is 0.4:1.

[0454] Wherein, in the step S3, the mass ratio of the stabilized zirconium oxide powder, water and the diluted dispersant is 100:300:0, the temperature of the mixture is controlled at 25°C, the mixing rate is 10-50Hz, and the mixing time is 10h.

[0455] Wherein, a dispersant is used to adjust the pH value of the solution system in step S3 to 6.5.

[0456] Wherein, in step S4, the mass ratio of the stabilized zirconia powder, water, diluted dispersant and diluted binder is 100:300:0:0.5, the temperature of the mixture is controlled at 25°C, the mixing rate is 50 Hz, and the mixing time is 10 hours.

[0457] Wherein, in step S5, the drying temperature is 270° C. and the drying time is 20 h.

[0458] Wherein, in the step S5, drying is performed by high-speed centrifugal spraying.

[0459] Comparative Example 2

[0460] This comparative example provides a method for preparing a zirconia composite powder, comprising the following steps: S1, providing stabilized zirconia powder, a dispersant and a binder; S2, diluting the dispersant and the binder with a diluent respectively; S3, mixing the stabilized zirconia powder, water and the diluted dispersant; S4, adding the diluted binder to the mixture obtained in step S3; S5, drying the mixture obtained in step S4 into powder to obtain the zirconia composite powder. Sodium polymethacrylate is used as a dispersant, and polyvinyl alcohol is used as a binder. The Tg of the binder used is 85°C.

[0461] The preparation of the stabilized zirconium oxide powder in step S1 includes the following steps: A1, dissolving zirconium nitrate in water to obtain an aqueous solution of zirconium nitrate; A2, adding a stabilizer to the aqueous solution system of step A1 to form stabilized zirconium oxide; A3, drying the mixture obtained in step A2 into powder; A4, sintering the powder obtained in step A3; A5, grinding and dispersing the product obtained in step A4 to obtain the stabilized zirconium oxide powder.

[0462] Wherein, in step A1, the mass ratio of zirconium nitrate to water is 1:0.6, the ambient temperature is 50° C., the stirring rate is 50 Hz, and the reaction time is 10 h.

[0463] Wherein, in step A2, the mass ratio of the stabilizer to zirconium nitrate is 0.16:1.

[0464] Wherein, in step A3, the drying equipment is any one of an oven, a microwave dryer, and a spray dryer, the drying temperature is 280° C., and the drying time is 20 hours.

[0465] Wherein, in step A4, the sintering equipment is a rotary kiln, the sintering temperature is 800°C, the heating time is 10 hours, the temperature is kept at 800°C for 4 hours, and the cooling time is 10 hours.

[0466] Wherein, in the step A5, the mesh size of the ground stabilized zirconia powder is 80 mesh, and the particle size of the stabilized zirconia powder obtained by granulation is 90 μm.

[0467] The D50 of the stabilized zirconia is 0.75 μm and the D90 is 1.11 μm; the stabilized zirconia contains 0.5% monoclinic phase and 99.5% tetragonal phase; the specific surface area of ​​the stabilized zirconia is 18 m 2 / g.

[0468] Wherein, in step S2, the diluent is pure water.

[0469] Wherein, in step S2, the mass ratio of the diluent to the dispersant is 0.4:4, and the mass ratio of the diluent to the binder is 0.4:1.

[0470] Wherein, in the step S3, the mass ratio of the stabilized zirconium oxide powder, water and the diluted dispersant is 100:300:40, the temperature of the mixture is controlled at 25°C, the mixing rate is 10-50Hz, and the mixing time is 10h.

[0471] Wherein, a dispersant is used to adjust the pH value of the solution system in step S3 to 9.1.

[0472] Wherein, in step S4, the mass ratio of the stabilized zirconia powder, water, diluted dispersant and diluted binder is 100:300:40:0.5, the temperature of the mixture is controlled at 25°C, the mixing rate is 50 Hz, and the mixing time is 10 hours.

[0473] Wherein, in step S5, the drying temperature is 270° C. and the drying time is 20 h.

[0474] Wherein, in the step S5, drying is performed by high-speed centrifugal spraying.

[0475] Comparative Example 3

[0476] This comparative example provides a method for preparing a zirconia composite powder, comprising the following steps: S1, providing stabilized zirconia powder, a dispersant and a binder; S2, diluting the dispersant and the binder with a diluent respectively; S3, mixing the stabilized zirconia powder, water and the diluted dispersant; S4, adding the diluted binder to the mixture obtained in step S3; S5, drying the mixture obtained in step S4 into powder to obtain the zirconia composite powder. Sodium polymethacrylate is used as a dispersant, and polyvinyl alcohol is used as a binder. The Tg of the binder used is 85°C.

[0477] The preparation of the stabilized zirconium oxide powder in step S1 includes the following steps: A1, dissolving zirconium nitrate in water to obtain an aqueous solution of zirconium nitrate; A2, adding a stabilizer to the aqueous solution system of step A1 to form stabilized zirconium oxide; A3, drying the mixture obtained in step A2 into powder; A4, sintering the powder obtained in step A3; A5, grinding and dispersing the product obtained in step A4 to obtain the stabilized zirconium oxide powder.

[0478] Wherein, in step A1, the mass ratio of zirconium nitrate to water is 1:0.8, the ambient temperature is 50° C., the stirring rate is 50 Hz, and the reaction time is 10 h.

[0479] Wherein, in step A2, the mass ratio of the stabilizer to zirconium nitrate is 0.16:1.

[0480] Wherein, in step A3, the drying equipment is any one of an oven, a microwave dryer, and a spray dryer, the drying temperature is 280° C., and the drying time is 20 hours.

[0481] Wherein, in step A4, the sintering equipment is a rotary kiln, the sintering temperature is 800°C, the heating time is 10 hours, the temperature is kept at 800°C for 4 hours, and the cooling time is 10 hours.

[0482] Wherein, in the step A5, the mesh size of the ground stabilized zirconia powder is 100 mesh, and the particle size of the stabilized zirconia powder obtained by granulation is 85 μm.

[0483] The D50 of the stabilized zirconia is 0.71 μm and the D90 is 1.01 μm; the stabilized zirconia contains 0.5% monoclinic phase and 99.5% tetragonal phase; the specific surface area of ​​the stabilized zirconia is 18 m 2 / g.

[0484] Wherein, in step S2, the diluent is pure water.

[0485] Wherein, in step S2, the mass ratio of the diluent to the dispersant is 0.4:8, and the mass ratio of the diluent to the binder is 0.4:1.

[0486] Wherein, in the step S3, the mass ratio of the stabilized zirconia powder, water and the diluted dispersant is 100:300:80, the temperature of the mixture is controlled at 25°C, the mixing rate is 10-50Hz, and the mixing time is 10h.

[0487] Wherein, a dispersant is used to adjust the pH value of the solution system in step S3 to 9.5.

[0488] Wherein, in step S4, the mass ratio of the stabilized zirconia powder, water, diluted dispersant and diluted binder is 100:300:80:0.5, the temperature of the mixture is controlled at 25°C, the mixing rate is 50 Hz, and the mixing time is 10 hours.

[0489] Wherein, in step S5, the drying temperature is 270° C. and the drying time is 20 h.

[0490] Wherein, in the step S5, drying is performed by high-speed centrifugal spraying.

[0491] Comparative Example 4

[0492] This comparative example provides a method for preparing a zirconia composite powder, comprising the following steps: S1, providing stabilized zirconia powder, a dispersant and a binder; S2, diluting the dispersant and the binder with a diluent respectively; S3, mixing the stabilized zirconia powder, water and the diluted dispersant; S4, adding the diluted binder to the mixture obtained in step S3; S5, drying the mixture obtained in step S4 into powder to obtain the zirconia composite powder. Sodium polymethacrylate is used as a dispersant, and polyvinyl alcohol is used as a binder. The Tg of the binder used is 85°C.

[0493] The preparation of the stabilized zirconium oxide powder in step S1 includes the following steps: A1, dissolving zirconium nitrate in water to obtain an aqueous solution of zirconium nitrate; A2, adding a stabilizer to the aqueous solution system of step A1 to form stabilized zirconium oxide; A3, drying the mixture obtained in step A2 into powder; A4, sintering the powder obtained in step A3; A5, grinding and dispersing the product obtained in step A4 to obtain the stabilized zirconium oxide powder.

[0494] Wherein, in step A1, the mass ratio of zirconium nitrate to water is 1:0.8, the ambient temperature is 50° C., the stirring rate is 50 Hz, and the reaction time is 10 h.

[0495] Wherein, in step A2, the mass ratio of the stabilizer to zirconium nitrate is 0.16:1.

[0496] Wherein, in step A3, the drying equipment is any one of an oven, a microwave dryer, and a spray dryer, the drying temperature is 280° C., and the drying time is 20 hours.

[0497] Wherein, in step A4, the sintering equipment is a rotary kiln, the sintering temperature is 800°C, the heating time is 10 hours, the temperature is kept at 800°C for 4 hours, and the cooling time is 10 hours.

[0498] Wherein, in the step A5, the mesh size of the ground stabilized zirconia powder is 100 mesh, and the particle size of the stabilized zirconia powder obtained by granulation is 85 μm.

[0499] The D50 of the stabilized zirconia is 0.71 μm and the D90 is 1.01 μm; the stabilized zirconia contains 0.5% monoclinic phase and 99.5% tetragonal phase; the specific surface area of ​​the stabilized zirconia is 18 m 2 / g.

[0500] Wherein, in step S2, the diluent is pure water.

[0501] Wherein, in step S2, the mass ratio of the diluent to the dispersant is 0.4:0.0003, and the mass ratio of the diluent to the binder is 0.4:1.

[0502] Wherein, in the step S3, the mass ratio of the stabilized zirconia powder, water and diluted dispersant is 100:300:0.003, the temperature of the mixture is controlled at 25°C, the mixing rate is 10-50Hz, and the mixing time is 13h.

[0503] Wherein, a dispersant is used to adjust the pH value of the solution system in step S3 to 6.8.

[0504] Wherein, in step S4, the mass ratio of the stabilized zirconia powder, water, diluted dispersant and diluted binder is 100:300:0.003:0.5, the temperature of the mixture is controlled at 25°C, the mixing rate is 50 Hz, and the mixing time is 13 hours.

[0505] Wherein, in step S5, the drying temperature is 280° C. and the drying time is 0.5 h.

[0506] Wherein, in the step S5, drying is performed by high-speed centrifugal spraying.

[0507] Comparative Example 5

[0508] This comparative example provides a method for preparing a zirconia composite powder, comprising the following steps: S1, providing stabilized zirconia powder, a dispersant and a binder; S2, diluting the dispersant and the binder with a diluent; S3, mixing the stabilized zirconia powder, water and the diluted dispersant; S4, adding the diluted binder to the mixture obtained in step S3; S5, drying the mixture obtained in step S4 into powder to obtain the zirconia composite powder. Sodium dodecyl sulfate is used as a dispersant, and polyvinyl alcohol is used as a binder. The Tg of the binder used is 85°C.

[0509] The preparation of the stabilized zirconium oxide powder in step S1 includes the following steps: A1, dissolving zirconium nitrate in water to obtain an aqueous solution of zirconium nitrate; A2, adding a stabilizer to the aqueous solution system of step A1 to form stabilized zirconium oxide; A3, drying the mixture obtained in step A2 into powder; A4, sintering the powder obtained in step A3; A5, grinding and dispersing the product obtained in step A4 to obtain the stabilized zirconium oxide powder.

[0510] Wherein, in step A1, the mass ratio of zirconium nitrate to water is 1:7.5, the ambient temperature is 40° C., the stirring rate is 20 Hz, and the reaction time is 15 h.

[0511] Wherein, in step A2, the mass ratio of the stabilizer to zirconium nitrate is 0.16:1.

[0512] Wherein, in step A3, the drying equipment is any one of an oven, a microwave dryer, and a spray dryer, the drying temperature is 280° C., and the drying time is 20 hours.

[0513] Wherein, in step A4, the sintering equipment is a rotary kiln, the sintering temperature is 800°C, the heating time is 10 hours, the temperature is kept at 800°C for 4 hours, and the cooling time is 10 hours.

[0514] Wherein, in the step A5, the mesh size of the ground stabilized zirconia powder is 100 mesh, and the particle size of the stabilized zirconia powder obtained by granulation is 85 μm.

[0515] The D50 of the stabilized zirconia is 0.71 μm and the D90 is 1.01 μm; the stabilized zirconia contains 0.5% monoclinic phase and 99.5% tetragonal phase; the specific surface area of ​​the stabilized zirconia is 18 m 2 / g.

[0516] Wherein, in step S2, the diluent is pure water.

[0517] Wherein, in step S2, the mass ratio of the diluent to the dispersant is 3:1, and the mass ratio of the diluent to the binder is 3:1.

[0518] Wherein, in the step S3, the mass ratio of the stabilized zirconia powder, water and the diluted dispersant is 100:300:4, the temperature of the mixture is controlled at 25°C, the mixing rate is 10-50Hz, and the mixing time is 13h.

[0519] Wherein, a dispersant is used to adjust the pH value of the solution system in step S3 to 7.9.

[0520] Wherein, in step S4, the mass ratio of the stabilized zirconia powder, water, diluted dispersant and diluted binder is 100:300:4:4, the temperature of the mixture is controlled at 25°C, the mixing rate is 50Hz, and the mixing time is 13h.

[0521] Wherein, in step S5, the drying temperature is 280° C. and the drying time is 0.5 h.

[0522] Wherein, in the step S5, drying is performed by high-speed centrifugal spraying.

[0523] Comparative Example 6

[0524] This comparative example provides a method for preparing a zirconia composite powder, comprising the following steps: S1, providing stabilized zirconia powder, a dispersant and a binder; S2, diluting the dispersant and the binder with a diluent; S3, mixing the stabilized zirconia powder, water and the diluted dispersant; S4, adding the diluted binder to the mixture obtained in step S3; S5, drying the mixture obtained in step S4 into powder to obtain the zirconia composite powder. Sodium dodecylbenzene sulfonate is used as a dispersant, and polyvinyl alcohol is used as a binder. The Tg of the binder used is 85°C.

[0525] The preparation of the stabilized zirconium oxide powder in step S1 includes the following steps: A1, dissolving zirconium nitrate in water to obtain an aqueous solution of zirconium nitrate; A2, adding a stabilizer to the aqueous solution system of step A1 to form stabilized zirconium oxide; A3, drying the mixture obtained in step A2 into powder; A4, sintering the powder obtained in step A3; A5, grinding and dispersing the product obtained in step A4 to obtain the stabilized zirconium oxide powder.

[0526] Wherein, in step A1, the mass ratio of zirconium nitrate to water is 1:8.5, the ambient temperature is 40° C., the stirring rate is 20 Hz, and the reaction time is 15 h.

[0527] Wherein, in step A2, the mass ratio of the stabilizer to zirconium nitrate is 0.16:1.

[0528] Wherein, in step A3, the drying equipment is any one of an oven, a microwave dryer, and a spray dryer, the drying temperature is 280° C., and the drying time is 20 hours.

[0529] Wherein, in step A4, the sintering equipment is a rotary kiln, the sintering temperature is 800°C, the heating time is 10 hours, the temperature is kept at 800°C for 4 hours, and the cooling time is 10 hours.

[0530] Wherein, in the step A5, the mesh size of the ground stabilized zirconia powder is 100 mesh, and the particle size of the stabilized zirconia powder obtained by granulation is 85 μm.

[0531] The D50 of the stabilized zirconia is 0.71 μm and the D90 is 1.01 μm; the stabilized zirconia contains 0.5% monoclinic phase and 99.5% tetragonal phase; the specific surface area of ​​the stabilized zirconia is 18 m 2 / g.

[0532] Wherein, in step S2, the diluent is pure water.

[0533] Wherein, in step S2, the mass ratio of the diluent to the dispersant is 3:1, and the mass ratio of the diluent to the binder is 3:1.

[0534] Wherein, in the step S3, the mass ratio of the stabilized zirconia powder, water and the diluted dispersant is 100:300:4, the temperature of the mixture is controlled at 25°C, the mixing rate is 10-50Hz, and the mixing time is 13h.

[0535] Wherein, a dispersant is used to adjust the pH value of the solution system in step S3 to 7.9.

[0536] Wherein, in step S4, the mass ratio of the stabilized zirconia powder, water, diluted dispersant and diluted binder is 100:300:4:4, the temperature of the mixture is controlled at 25°C, the mixing rate is 50Hz, and the mixing time is 13h.

[0537] Wherein, in step S5, the drying temperature is 280° C. and the drying time is 0.5 h.

[0538] Wherein, in the step S5, drying is performed by high-speed centrifugal spraying.

[0539] Comparative Example 7

[0540] This comparative example provides a method for preparing a zirconia composite powder, comprising the following steps: S1, providing stabilized zirconia powder, a dispersant and a binder; S2, diluting the dispersant and the binder with a diluent respectively; S3, mixing the stabilized zirconia powder, water and the diluted dispersant; S4, adding the diluted binder to the mixture obtained in step S3; S5, drying the mixture obtained in step S4 into powder to obtain the zirconia composite powder. Sodium polymethacrylate is used as a dispersant, and polyvinyl alcohol is used as a binder. The Tg of the binder used is 85°C.

[0541] The preparation of the stabilized zirconium oxide powder in step S1 includes the following steps: A1, dissolving zirconium nitrate in water to obtain an aqueous solution of zirconium nitrate; A2, adding a stabilizer to the aqueous solution system of step A1 to form stabilized zirconium oxide; A3, drying the mixture obtained in step A2 into powder; A4, sintering the powder obtained in step A3; A5, grinding and dispersing the product obtained in step A4 to obtain the stabilized zirconium oxide powder.

[0542] Wherein, in step A1, the mass ratio of zirconium nitrate to water is 1:9, the ambient temperature is 40° C., the stirring rate is 20 Hz, and the reaction time is 15 h.

[0543] Wherein, in step A2, the mass ratio of the stabilizer to zirconium nitrate is 0.16:1.

[0544] Wherein, in step A3, the drying equipment is any one of an oven, a microwave dryer, and a spray dryer, the drying temperature is 270° C., and the drying time is 20 hours.

[0545] Wherein, in step A4, the sintering equipment is a rotary kiln, the sintering temperature is 800°C, the heating time is 10 hours, the temperature is kept at 800°C for 4 hours, and the cooling time is 10 hours.

[0546] Wherein, in the step A5, the mesh size of the ground stabilized zirconia powder is 200 mesh, and the particle size of the stabilized zirconia powder obtained by granulation is 64 μm.

[0547] The D50 of the stabilized zirconia is 0.70 μm and the D90 is 1.05 μm; the stabilized zirconia contains 0.5% monoclinic phase and 99.5% tetragonal phase; the specific surface area of ​​the stabilized zirconia is 18 m 2 / g.

[0548] Wherein, in step S2, the diluent is pure water.

[0549] Wherein, in step S2, the mass ratio of the diluent to the dispersant is 0.4:1, and the mass ratio of the diluent to the binder is 0.4:0.0003.

[0550] Wherein, in the step S3, the mass ratio of the stabilized zirconia powder, water and the diluted dispersant is 100:300:1, the temperature of the mixture is controlled at 25°C, the mixing rate is 10-50Hz, and the mixing time is 13h.

[0551] Wherein, a dispersant is used to adjust the pH value of the solution system in step S3 to 7.9.

[0552] Wherein, in step S4, the mass ratio of the stabilized zirconia powder, water, diluted dispersant and diluted binder is 100:300:1:0.003, the temperature of the mixture is controlled at 25°C, the mixing rate is 50Hz, and the mixing time is 13h.

[0553] Wherein, in step S5, the drying temperature is 280° C. and the drying time is 0.5 h.

[0554] Wherein, in the step S5, drying is performed by high-speed centrifugal spraying.

[0555] Comparative Example 8

[0556] This comparative example provides a method for preparing a zirconia composite powder, comprising the following steps: S1, providing stabilized zirconia powder, a dispersant and a binder; S2, diluting the dispersant and the binder with a diluent respectively; S3, mixing the stabilized zirconia powder, water and the diluted dispersant; S4, adding the diluted binder to the mixture obtained in step S3; S5, drying the mixture obtained in step S4 into powder to obtain the zirconia composite powder. Sodium polymethacrylate is used as a dispersant, and polyvinyl alcohol is used as a binder. The Tg of the binder used is 85°C.

[0557] The preparation of the stabilized zirconium oxide powder in step S1 includes the following steps: A1, dissolving zirconium nitrate in water to obtain an aqueous solution of zirconium nitrate; A2, adding a stabilizer to the aqueous solution system of step A1 to form stabilized zirconium oxide; A3, drying the mixture obtained in step A2 into powder; A4, sintering the powder obtained in step A3; A5, grinding and dispersing the product obtained in step A4 to obtain the stabilized zirconium oxide powder.

[0558] Wherein, in step A1, the mass ratio of zirconium nitrate to water is 1:9, the ambient temperature is 40° C., the stirring rate is 20 Hz, and the reaction time is 15 h.

[0559] Wherein, in step A2, the mass ratio of the stabilizer to zirconium nitrate is 0.16:1.

[0560] Wherein, in step A3, the drying equipment is any one of an oven, a microwave dryer, and a spray dryer, the drying temperature is 270° C., and the drying time is 20 hours.

[0561] Wherein, in step A4, the sintering equipment is a rotary kiln, the sintering temperature is 800°C, the heating time is 10 hours, the temperature is kept at 800°C for 4 hours, and the cooling time is 10 hours.

[0562] Wherein, in the step A5, the mesh size of the ground stabilized zirconia powder is 200 mesh, and the particle size of the stabilized zirconia powder obtained by granulation is 64 μm.

[0563] The D50 of the stabilized zirconia is 0.70 μm and the D90 is 1.05 μm; the stabilized zirconia contains 0.5% monoclinic phase and 99.5% tetragonal phase; the specific surface area of ​​the stabilized zirconia is 18 m 2 / g.

[0564] Wherein, in step S2, the diluent is pure water.

[0565] Wherein, in step S2, the mass ratio of the diluent to the dispersant is 0.4:1, and the mass ratio of the diluent to the binder is 0.4:8.

[0566] Wherein, in the step S3, the mass ratio of the stabilized zirconia powder, water and the diluted dispersant is 120:300:14, the temperature of the mixture is controlled at 25°C, the mixing rate is 10-50Hz, and the mixing time is 13h.

[0567] Wherein, a dispersant is used to adjust the pH value of the solution system in step S3 to 7.9.

[0568] Wherein, in step S4, the mass ratio of the stabilized zirconia powder, water, diluted dispersant and diluted binder is 120:300:14:0.04, the temperature of the mixture is controlled at 25°C, the mixing rate is 50Hz, and the mixing time is 13h.

[0569] Wherein, in step S5, the drying temperature is 280° C. and the drying time is 0.5 h.

[0570] Wherein, in the step S5, drying is performed by high-speed centrifugal spraying.

[0571] Comparative Example 9

[0572] This comparative example provides a method for preparing a zirconia composite powder, comprising the following steps: S1, providing stabilized zirconia powder, a dispersant and a binder; S2, diluting the dispersant and the binder with a diluent; S3, mixing the stabilized zirconia powder, water and the diluted dispersant; S4, adding the diluted binder to the mixture obtained in step S3; S5, drying the mixture obtained in step S4 into powder to obtain the zirconia composite powder. Sodium polymethacrylate is used as a dispersant, and polyvinyl alcohol is used as a binder. The Tg of the binder used is 60°C.

[0573] The preparation of the stabilized zirconium oxide powder in step S1 includes the following steps: A1, dissolving zirconium nitrate in water to obtain an aqueous solution of zirconium nitrate; A2, adding a stabilizer to the aqueous solution system of step A1 to form stabilized zirconium oxide; A3, drying the mixture obtained in step A2 into powder; A4, sintering the powder obtained in step A3; A5, grinding and dispersing the product obtained in step A4 to obtain the stabilized zirconium oxide powder.

[0574] Wherein, in step A1, the mass ratio of zirconium nitrate to water is 1:9, the ambient temperature is 40° C., the stirring rate is 20 Hz, and the reaction time is 15 h.

[0575] Wherein, in step A2, the mass ratio of the stabilizer to zirconium nitrate is 0.16:1.

[0576] Wherein, in step A3, the drying equipment is any one of an oven, a microwave dryer, and a spray dryer, the drying temperature is 270° C., and the drying time is 20 hours.

[0577] Wherein, in step A4, the sintering equipment is a rotary kiln, the sintering temperature is 1300° C., the heating time is 12 hours, the temperature is kept at 1300° C. for 10 hours, and the cooling time is 15 hours.

[0578] Wherein, in the step A5, the mesh size of the ground stabilized zirconia powder is 300 mesh, and the particle size of the stabilized zirconia powder obtained by granulation is 52 μm.

[0579] The D50 of the stabilized zirconia is 0.08 μm and the D90 is 0.18 μm; the stabilized zirconia contains 0.5% monoclinic phase and 99.5% tetragonal phase; the specific surface area of ​​the stabilized zirconia is 6.9 m 2 / g.

[0580] Wherein, in step S2, the diluent is pure water.

[0581] Wherein, in step S2, the mass ratio of the diluent to the dispersant is 3:1, and the mass ratio of the diluent to the binder is 3:1.

[0582] Wherein, in the step S3, the mass ratio of the stabilized zirconia powder, water and the diluted dispersant is 100:300:4, the temperature of the mixture is controlled at 25°C, the mixing rate is 10-50Hz, and the mixing time is 13h.

[0583] Wherein, a dispersant is used to adjust the pH value of the solution system in step S3 to 7.9.

[0584] Wherein, in step S4, the mass ratio of the stabilized zirconia powder, water, diluted dispersant and diluted binder is 100:300:4:4, the temperature of the mixture is controlled at 25°C, the mixing rate is 50Hz, and the mixing time is 13h.

[0585] Wherein, in step S5, the drying temperature is 280° C. and the drying time is 0.5 h.

[0586] Wherein, in the step S5, drying is performed by high-speed centrifugal spraying.

[0587] Comparative Example 10

[0588] This comparative example provides a method for preparing a zirconia composite powder, comprising the following steps: S1, providing stabilized zirconia powder, a dispersant and a binder; S2, diluting the dispersant and the binder with a diluent; S3, mixing the stabilized zirconia powder, water and the diluted dispersant; S4, adding the diluted binder to the mixture obtained in step S3; S5, drying the mixture obtained in step S4 into powder to obtain the zirconia composite powder. Sodium polymethacrylate is used as a dispersant, and polyvinyl alcohol is used as a binder. The Tg of the binder used is 91°C.

[0589] The preparation of the stabilized zirconium oxide powder in step S1 includes the following steps: A1, dissolving zirconium nitrate in water to obtain an aqueous solution of zirconium nitrate; A2, adding a stabilizer to the aqueous solution system of step A1 to form stabilized zirconium oxide; A3, drying the mixture obtained in step A2 into powder; A4, sintering the powder obtained in step A3; A5, grinding and dispersing the product obtained in step A4 to obtain the stabilized zirconium oxide powder.

[0590] Wherein, in step A1, the mass ratio of zirconium nitrate to water is 1:10, the ambient temperature is 40° C., the stirring rate is 50 Hz, and the reaction time is 15 h.

[0591] Wherein, in step A2, the mass ratio of the stabilizer to zirconium nitrate is 0.16:1.

[0592] Wherein, in step A3, the drying equipment is any one of an oven, a microwave dryer, and a spray dryer, the drying temperature is 270° C., and the drying time is 20 hours.

[0593] Wherein, in step A4, the sintering equipment is a rotary kiln, the sintering temperature is 1400° C., the heating time is 12 hours, the temperature is kept at 1400° C. for 10 hours, and the cooling time is 15 hours.

[0594] Wherein, in the step A5, the mesh size of the ground stabilized zirconia powder is 300 mesh, and the particle size of the stabilized zirconia powder obtained by granulation is 52 μm.

[0595] The D50 of the stabilized zirconia is 0.08 μm and the D90 is 0.18 μm; the stabilized zirconia contains 0.05% monoclinic phase and 99.8% tetragonal phase; the specific surface area of ​​the stabilized zirconia is 4.8 m 2 / g.

[0596] Wherein, in step S2, the diluent is pure water.

[0597] Wherein, in step S2, the mass ratio of the diluent to the dispersant is 3:1, and the mass ratio of the diluent to the binder is 3:1.

[0598] Wherein, in the step S3, the mass ratio of the stabilized zirconia powder, water and the diluted dispersant is 100:300:4, the temperature of the mixture is controlled at 25°C, the mixing rate is 10-50Hz, and the mixing time is 13h.

[0599] Wherein, a dispersant is used to adjust the pH value of the solution system in step S3 to 7.9.

[0600] Wherein, in step S4, the mass ratio of the stabilized zirconia powder, water, diluted dispersant and diluted binder is 100:300:4:4, the temperature of the mixture is controlled at 25°C, the mixing rate is 50Hz, and the mixing time is 13h.

[0601] Wherein, in step S5, the drying temperature is 280° C. and the drying time is 0.5 h.

[0602] Wherein, in the step S5, drying is performed by high-speed centrifugal spraying.

[0603] Comparative Example 11

[0604] This comparative example provides a method for preparing a zirconia composite powder, comprising the following steps: S1, providing stabilized zirconia powder, a dispersant and a binder; S2, diluting the dispersant and the binder with a diluent; S3, mixing the stabilized zirconia powder, water and the diluted dispersant; S4, adding the diluted binder to the mixture obtained in step S3; S5, drying the mixture obtained in step S4 into powder to obtain the zirconia composite powder. Sodium polymethacrylate is used as a dispersant, and epoxy resin is used as a binder. The Tg of the binder used is 85°C.

[0605] The preparation of the stabilized zirconium oxide powder in step S1 includes the following steps: A1, dissolving zirconium nitrate in water to obtain an aqueous solution of zirconium nitrate; A2, adding a stabilizer to the aqueous solution system of step A1 to form stabilized zirconium oxide; A3, drying the mixture obtained in step A2 into powder; A4, sintering the powder obtained in step A3; A5, grinding and dispersing the product obtained in step A4 to obtain the stabilized zirconium oxide powder.

[0606] Wherein, in step A1, the mass ratio of zirconium nitrate to water is 1:11, the ambient temperature is 40° C., the stirring rate is 50 Hz, and the reaction time is 15 h.

[0607] Wherein, in step A2, the mass ratio of the stabilizer to zirconium nitrate is 0.16:1.

[0608] Wherein, in step A3, the drying equipment is any one of an oven, a microwave dryer, and a spray dryer, the drying temperature is 270° C., and the drying time is 20 hours.

[0609] Wherein, in step A4, the sintering equipment is a rotary kiln, the sintering temperature is 1400° C., the heating time is 12 hours, the temperature is kept at 1400° C. for 10 hours, and the cooling time is 15 hours.

[0610] Wherein, in the step A5, the mesh size of the ground stabilized zirconia powder is 300 mesh, and the particle size of the stabilized zirconia powder obtained by granulation is 52 μm.

[0611] The D50 of the stabilized zirconia is 0.08 μm and the D90 is 0.18 μm; the stabilized zirconia contains 0.05% monoclinic phase and 99.8% tetragonal phase; the specific surface area of ​​the stabilized zirconia is 4.8 m 2 / g.

[0612] Wherein, in step S2, the diluent is pure water.

[0613] Wherein, in step S2, the mass ratio of the diluent to the dispersant is 3:1, and the mass ratio of the diluent to the binder is 3:1.

[0614] Wherein, in the step S3, the mass ratio of the stabilized zirconia powder, water and the diluted dispersant is 100:300:4, the temperature of the mixture is controlled at 25°C, the mixing rate is 10-50Hz, and the mixing time is 13h.

[0615] Wherein, a dispersant is used to adjust the pH value of the solution system in step S3 to 7.6.

[0616] Wherein, in step S4, the mass ratio of the stabilized zirconia powder, water, diluted dispersant and diluted binder is 100:300:4:4, the temperature of the mixture is controlled at 25°C, the mixing rate is 50Hz, and the mixing time is 13h.

[0617] Wherein, in step S5, the drying temperature is 280° C. and the drying time is 21 h.

[0618] Wherein, in the step S5, drying is performed by high-speed centrifugal spraying.

[0619] Comparative Example 12

[0620] This comparative example provides a method for preparing a zirconia composite powder, comprising the following steps: S1, providing stabilized zirconia powder, a dispersant and a binder; S2, diluting the dispersant and the binder with a diluent; S3, mixing the stabilized zirconia powder, water and the diluted dispersant; S4, adding the diluted binder to the mixture obtained in step S3; S5, drying the mixture obtained in step S4 into powder to obtain the zirconia composite powder. Sodium polymethacrylate is used as a dispersant, and polyurethane is used as a binder. The Tg of the binder used is 85°C.

[0621] The preparation of the stabilized zirconium oxide powder in step S1 includes the following steps: A1, dissolving zirconium nitrate in water to obtain an aqueous solution of zirconium nitrate; A2, adding a stabilizer to the aqueous solution system of step A1 to form stabilized zirconium oxide; A3, drying the mixture obtained in step A2 into powder; A4, sintering the powder obtained in step A3; A5, grinding and dispersing the product obtained in step A4 to obtain the stabilized zirconium oxide powder.

[0622] Wherein, in step A1, the mass ratio of zirconium nitrate to water is 1:11, the ambient temperature is 40° C., the stirring rate is 50 Hz, and the reaction time is 15 h.

[0623] Wherein, in step A2, the mass ratio of the stabilizer to zirconium nitrate is 0.16:1.

[0624] Wherein, in step A3, the drying equipment is any one of an oven, a microwave dryer, and a spray dryer, the drying temperature is 270° C., and the drying time is 20 hours.

[0625] Wherein, in step A4, the sintering equipment is a rotary kiln, the sintering temperature is 1450° C., the heating time is 12 hours, the temperature is kept at 1450° C. for 12 hours, and the cooling time is 20 hours.

[0626] Wherein, in the step A5, the mesh size of the ground stabilized zirconia powder is 300 mesh, and the particle size of the stabilized zirconia powder obtained by granulation is 52 μm.

[0627] The D50 of the stabilized zirconia is 0.08 μm and the D90 is 0.18 μm; the stabilized zirconia contains 0.05% monoclinic phase and 99.8% tetragonal phase; the specific surface area of ​​the stabilized zirconia is 4.1 m 2 / g.

[0628] Wherein, in step S2, the diluent is pure water.

[0629] Wherein, in step S2, the mass ratio of the diluent to the dispersant is 3:1, and the mass ratio of the diluent to the binder is 3:1.

[0630] Wherein, in the step S3, the mass ratio of the stabilized zirconia powder, water and the diluted dispersant is 100:300:4, the temperature of the mixture is controlled at 25°C, the mixing rate is 10-50Hz, and the mixing time is 13h.

[0631] Wherein, a dispersant is used to adjust the pH value of the solution system in step S3 to 7.6.

[0632] Wherein, in step S4, the mass ratio of the stabilized zirconia powder, water, diluted dispersant and diluted binder is 100:300:4:4, the temperature of the mixture is controlled at 25°C, the mixing rate is 50Hz, and the mixing time is 13h.

[0633] Wherein, in step S5, the drying temperature is 280° C. and the drying time is 21 h.

[0634] Wherein, in the step S5, drying is performed by high-speed centrifugal spraying.

[0635] The zirconium oxide powder obtained in the above-mentioned embodiments and comparative examples is made into a dental restoration through the following steps: A10, powder dry pressing: placing the zirconium oxide composite powder into a dry pressing machine mold for pressing; A20, cold isostatic pressing: sealing the pressed zirconium oxide composite powder obtained in step A10, and placing it in a cold isostatic press for pressurization and exhaust; A30, bisque firing and debinding: heating the bisque-pressed zirconium oxide composite powder obtained in step A20; A40, final firing and porcelainization: firing the bisque-fired zirconium oxide composite powder obtained in step A30 to obtain a bisque; A50, post-processing: polishing, glazing and shaping the bisque obtained in step A40 to obtain the dental restoration; wherein, in step A10, the pressing pressure is 20 MPa; in step A20, the cold isostatic pressing pressure is 200 MPa; in step A30, the heating temperature is 1050°C; in step A40, the firing temperature is 1450°C.

[0636] The properties of the zirconium oxide composite powders obtained in the above embodiments and comparative examples were tested as follows:

[0637] Bulk density test method:

[0638] Funnel method: Before testing, level the instrument first, rotate the level adjustment foot to adjust the bubble of the level indicator of the bulk density tester to the center point; use the iron cone rod provided by the instrument to block the feed port of the tester, then pour the powder into the funnel, pull out the iron cone rod, and let the powder flow freely and fall into the receiving container. After falling, use an iron ruler to scrape the surface of the receiving container to remove the excess material; record the mass and volume of the outflowing powder (the fixed volume of the container is 100cm 3 ) and calculate the bulk density (GB / T 1479.1-2011).

[0639] The calculation formula for bulk density is: weight (g) ÷ 100 = bulk density, the unit is g / cm3.

[0640] Sphericity test method:

[0641] Sphericity ratio: Before testing, shake the powder evenly and pour it on the double-sided tape. Use an ear bulb to blow off the unattached powder to spread the powder particles evenly. Adjust the microscope to a fixed magnification and record the total number of powder particles in the microscope field of view as A. Compare it with the standard critical sphere. The total number of "apple-shaped balls", "shrunken balls" and "agglomerates of multiple balls" with worse sphericity than the critical sphere is recorded as B.

[0642] The sphericity ratio calculation formula is: (AB) / A*100%.

[0643] Hollowness test method:

[0644] Hollowness ratio: According to the sample preparation method of sphericity ratio, after the powder is spread on the double-sided tape, a new double-sided tape is used to stick to the double-sided tape with the powder, and then gently pressed and torn off (the purpose is to peel off the particles and reveal the cross section of the particle sphere). Adjust the microscope to a fixed magnification, record the total number of particles in the powder cross section within the microscope field of view and record it as A. According to the hollow ball judgment standard: hollow area> 1 / 2 of the sphere is judged as a hollow ball, and the total number is recorded as B.

[0645] The calculation formula for hollowness ratio: B / A*100%.

[0646] Forming rate test method:

[0647] Dry pressing: Use dust-free paper dipped in a little alcohol to wipe the top and bottom molds of the tablet press clean, use a sampling spoon to pour the material into the bottom mold, use a scraper to level the material and the surface of the bottom mold, click to start the hydraulic system to start pressing, press 100 samples each time, after the dry pressing is completed, take out the material block and confirm the number of cracks in the sample block, which is recorded as A.

[0648] Isostatic pressing: Put the material block into a plastic bag, seal the opening with a plastic sealing machine to ensure that there is no air leakage, and perform isostatic pressing according to the isostatic pressing curve. After the isostatic pressing is completed, use scissors to cut open the plastic bag, take out the material block and confirm the number of cracks in the sample, which is recorded as B.

[0649] Pre-sintering: Set the temperature of the muffle furnace, place the material block upright on the crucible, and sinter according to the sintering curve. After sintering, take out the material block to confirm the number of cracks on the sample, which is recorded as C.

[0650] The formula for calculating the molding rate ratio is: (A+B+C) / 10*100%.

[0651] The performance results of the zirconium oxide composite powders obtained in all the examples and comparative examples described in the specification of the present invention measured by the above test method are listed in the following table.

[0652] Table 1 Performance data of zirconium oxide composite powders of Examples 1 to 10

[0653]

[0654] Table 2 Performance data of zirconium oxide composite powders of Examples 11 to 20

[0655]

[0656]

[0657] It can be seen from Table 1 and Table 2 above that the sphericity of Examples 1 to 20 meets 80 to 95%, the hollowness is 1 to 10% and the forming rate is greater than 95%.

[0658] As shown in Table 1, the dilution ratio of the dispersant in Examples 1 to 10 is optimal at 1:(0.5-7), with the best dispersion effect and sphericity of more than 90%; due to the strong interaction between the hydrophilic chain segments of the dispersant and the water molecules, the dispersant forms a hydration layer after dilution, reducing the probability of particle collision. Sodium polymethacrylate can make the Zeta potential of zirconium oxide particles reach more than -40mV. With the increase in dosage, the Zeta potential of the particles in the slurry changes from positive to negative, significantly inhibiting hard agglomeration, narrowing the powder particle size distribution, and the primary particles no longer clumping together, and the densification rate is increased.

[0659] As can be seen from Table 1, the optimal dilution ratio of the binder in Examples 1 to 10 is 1:(0.5-6), and the hollowness is within 6%. The dense hydroxyl groups (—OH) on the molecular chain of polyvinyl alcohol (PVA) can form a strong hydrogen bond network with the —OH on the surface of zirconium oxide, and at the same time form a flexible polymer chain bridge between the powders. This dual effect (surface adsorption + chain entanglement) imparts high bonding strength, and the surface tension of the PVA aqueous solution (about 40-50 mN / m) and the surface energy of zirconium oxide (about 60 mJ / m 2 ) can fully wet the particle surface and reduce the porosity.

[0660] It can be seen from Table 1 that the forming rates of Examples 1, 2, 8, and 9 are ≥98%, and the Tg of the binder satisfies 85°C to 90°C. Within this range, the binder partially enters a highly elastic state, the flexibility of the molecular chain increases, the particles are rearranged through the viscoelastic creep of the binder film, the drying stress is released, and the gaps between the particles are filled through viscoelastic flow, avoiding microcracks caused by too fast solvent evaporation, thereby improving the green density.

[0661] As shown in Tables 1 and 2, the ratio of stabilizer to zirconium nitrate in Examples 1 to 9 is optimal at (0.01-0.06):1, and the forming rate is ≥96%. When the ratio of stabilizer to zirconium nitrate is (0.13-0.16):1, the forming rate decreases. In zirconium oxide doped with an appropriate amount of yttria, a martensitic phase transformation (t→m) will occur at room temperature. This phase transformation is accompanied by volume expansion, which compresses the crack tip and hinders crack propagation, and can significantly improve the fracture toughness of the material. And Y 3+ Segregation at grain boundaries can pin grain boundary migration, inhibit abnormal grain growth during sintering, maintain a fine-grained structure, and thus improve high-temperature mechanical properties.

[0662] Table 3 Performance data of zirconium oxide composite powders of comparative examples 1 to 10

[0663]

[0664]

[0665] As shown in Table 3, in Comparative Examples 1 to 4, when low or excessive amounts of dispersant are added, the sphericity of the zirconium oxide powder is ≤66% and the hollowness is ≥33%. In Comparative Example 1, when no more dispersant is added, the sphericity reaches a minimum of 48% and the forming rate reaches a minimum of 43%. This is because too low or excessive amounts of dispersant will destroy the carboxylate groups (—COO - ) and the —OH or —O - The adsorption layer cannot be effectively formed due to the low entropy repulsion when the particles are close to each other, and the particle agglomeration increases, resulting in low sphericity and poor forming rate.

[0666] As can be seen from Table 3, Comparative Examples 5 and 6 use non-sodium polymethacrylate dispersants, which leads to a decrease in the sphericity and molding rate ratio and an increase in the hollowness ratio. The main reason is that the dispersant has weak adsorption and poor stability. When added to the zirconia slurry as a dispersant, the repulsion between the particles cannot achieve the effect of resistance agglomeration. Comparative Example 7 is a low-amount binder verification. Too low a binder addition leads to the inability to effectively form a flexible polymer chain bridge between the zirconia powders, which reduces the strength and leads to a low molding rate. Comparative Example 8 is an excessive binder verification. Excessive binder addition leads to dense zirconia powder particles and hard particles. When pressed by a mold, the particles cannot be effectively broken, resulting in difficulty in molding.

[0667] As can be seen from Table 3, non-polyvinyl alcohol binders are added to Comparative Examples 11 and 12 respectively. After other binders are added to the zirconia slurry, they cannot form a strong hydrogen bond network with the -OH on the surface of zirconia, and the flexible polymer chain bridging force between powders is weak, and there is a risk of bond breaking, resulting in weak adhesion, poor stability and low molding rate of zirconia powder.

[0668] The above is only a specific implementation of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention shall be based on the protection scope of the claims. In addition, the specification uses specific examples to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core idea. The content of this specification should not be understood as a limitation on the present invention.

Claims

1. A zirconium oxide composite powder, characterized in that: The bulk density of the zirconium oxide composite powder is 1 to 1.3 g / cm 3 , sphericity of 80-95%, hollowness of 1-10% and particle size of 35-75 μm.

2. The zirconium oxide composite powder according to claim 1, characterized in that: The zirconium oxide composite powder contains zirconium oxide, a stabilizer, a dispersant and a binder.

3. The zirconium oxide composite powder according to claim 2, characterized in that: The stabilizer is at least one of yttrium oxide, erbium oxide, and ytterbium oxide. Preferably, the zirconium oxide and the stabilizer are present in the form of stabilized zirconium oxide.

4. The zirconium oxide composite powder according to claim 2, characterized in that: The dispersant is at least one of polyether acid compounds, polyether compounds, ether compounds, fatty acid salt compounds, polyphosphate compounds, polycarboxylic acid compounds, phosphate ester compounds, polyether amine compounds, and polymethacrylate compounds, preferably a polymethacrylate compound.

5. The zirconium oxide composite powder according to claim 2, characterized in that: The binder is at least one of polyvinyl alcohol, polyethylene glycol, cellulose, alginates, and polymethyl methacrylate, preferably polyvinyl alcohol.

6. The zirconium oxide composite powder according to claim 5, characterized in that: The glass transition temperature Tg of the binder is 65-90°C.

7. The zirconium oxide composite powder according to claim 2, characterized in that: The zirconium oxide composite powder comprises 85-100% zirconium oxide, 1-16% stabilizer, 0.05-1.5% dispersant, and 0.05~1.0% binder.

8. The zirconium oxide composite powder according to any one of claims 1 to 7, characterized in that: The zirconium oxide comprises monoclinic zirconium oxide and tetragonal zirconium oxide, and preferably comprises 0.5% to 4% of monoclinic zirconium oxide and 96% to 99.5% of tetragonal zirconium oxide.

9. A method for preparing the zirconium oxide composite powder according to claims 1 to 8, characterized in that: The following steps are involved: S1, providing stabilized zirconium oxide powder, dispersant and binder; S2, optionally diluting the dispersant and the binder respectively with a diluent; S3, mixing the stabilized zirconium oxide powder, water and an optionally diluted dispersant; S4, adding the optionally diluted binder to the mixture obtained in step S3; S5, drying the mixture obtained in step S4 into powder to obtain the zirconium oxide composite powder.

10. The method according to claim 9, characterized in that The preparation of the stabilized zirconium oxide powder in step S1 comprises the following steps: A1, dissolving zirconium nitrate in water to obtain an aqueous solution of zirconium nitrate, wherein the zirconium nitrate is preferably selected from at least one of zirconium oxychloride, zirconium chloride, zirconium sulfate and zirconium nitrate; A2, adding a stabilizer to the aqueous solution system of step A1 to form stabilized zirconium oxide; A3, drying the stabilized zirconium oxide obtained in step A2 into powder; A4, sintering the powder obtained in step A3; A5, grinding and dispersing the product obtained in step A4 to obtain the stabilized zirconium oxide powder.

11. The method according to claim 10, characterized in that Have at least one of the following characteristics: In the step A1, the mass ratio of zirconium nitrate to water is 1:(1-7); In the step A2, the mass ratio of the stabilizer to zirconium nitrate is (0.01-0.16):1; In step A3, the drying equipment is any one of an oven, a microwave dryer, and a spray dryer, the drying temperature is 150 to 270° C., and the drying time is 1 to 20 hours; In the step A4, the sintering equipment is any one of a high temperature furnace, a bell furnace, a box furnace, a push plate furnace, a roller furnace, and a rotary furnace. The sintering temperature is 900-1200° C., the heating time is 1.5-10 hours, the temperature is kept at 900-1200° C. for 0.5-4 hours, and the cooling time is 3-10 hours.

12. The method according to any one of claims 9 to 11, characterized in that: Have at least one of the following characteristics: The particle size D50 of the stabilized zirconia is 0.1 to 0.5 μm and the D90 is 0.2 to 1 μm; The stabilized zirconia comprises monoclinic zirconia and tetragonal zirconia, preferably 0.5-4% monoclinic zirconia and 96-99.5% tetragonal zirconia; The specific surface area of ​​the stabilized zirconia is 10 to 15 m 2 / g.

13. The method according to claim 9, characterized in that In the step S2, the diluent is at least one of alcohols, ethers, esters and water.

14. The method according to claim 13, characterized in that In the step S2, the mass ratio of the diluent to the dispersant is (0.5-20):1; And / or, the mass ratio of the diluent to the binder is (0.5-10):

1.

15. The method according to claim 9, characterized in that In the step S3, the mass ratio of the stabilized zirconium oxide powder, water and the diluted dispersant is (80-120):(100-300):(5-10), the temperature of the mixture is controlled at 10-50° C., for example, 25° C., the mixing rate is 10-50 Hz, and the mixing time is 0.5-10 h; And / or, the pH value of the dispersant is 7.5 to 9, preferably 7.5 to 8.

5.

16. The method according to claim 9, characterized in that In step S4, the mass ratio of the stabilized zirconia powder, water, diluted dispersant and diluted binder is (80-120):(100-300):(5-10):(1-80), the temperature of the mixture is controlled at 10-50°C, for example, 25°C, the mixing rate is 10-50Hz, and the mixing time is 0.5-10h.

17. The method according to claim 9, characterized in that The method has at least one of the following characteristics: In step S5, the drying temperature is 150-270° C., and the drying time is 1-20 hours; In the step S5, drying is performed by using any one of rotary flash evaporation, high-speed centrifugal spraying, blade drying, and boiling drying, or a combination of at least two of the methods; In the step S5, the mesh number of the stabilized zirconium oxide powder granulated by the drying equipment is 100-500 mesh, and the particle size of the stabilized zirconium oxide powder obtained by granulation is 35-75 μm.

18. A dental restoration, characterized in that: The dental restoration is made from the zirconium oxide composite powder according to any one of claims 1 to 8, or is made from the zirconium oxide composite powder obtained by the method according to any one of claims 9 to 17.

19. A method for preparing a dental restoration according to claim 18, characterized in that The method comprises the following steps: A10, powder dry pressing: placing the zirconium oxide composite powder into a dry pressing machine mold for pressing; A20, cold isostatic pressing: the compressed zirconium oxide composite powder obtained in step A10 is sealed in plastic and placed in a cold isostatic press to pressurize and exhaust; A30, bisque firing and debinding: heating the zirconia composite powder obtained in step A20 and being cooled and isostatically pressed; A40, final firing of porcelain: firing the bisque-fired zirconium oxide composite powder obtained in step A30 to obtain a bisque; A50, post-processing: polishing, glazing and reshaping the blank obtained in step A40 to obtain the dental restoration.

20. The method according to claim 19, characterized in that Have at least one of the following characteristics: In the step A10, the pressing pressure is 15-25 MPa; In the step A20, the pressure of the cold isostatic pressing is 180-250 MPa; In the step A30, the heating temperature is 1000-1100° C.; In the step A40, the firing temperature is 1400-1500°C.

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