CN111302777A - Alumina ceramic, preparation method thereof and ceramic bearing - Google Patents

Alumina ceramic, preparation method thereof and ceramic bearing Download PDF

Info

Publication number
CN111302777A
CN111302777A CN202010122991.6A CN202010122991A CN111302777A CN 111302777 A CN111302777 A CN 111302777A CN 202010122991 A CN202010122991 A CN 202010122991A CN 111302777 A CN111302777 A CN 111302777A
Authority
CN
China
Prior art keywords
ceramic
alumina
sintering
oxide
raw materials
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN202010122991.6A
Other languages
Chinese (zh)
Inventor
朱佐祥
谭毅成
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Shenzhen Suntech Advanced Ceramics Co ltd
Original Assignee
Shenzhen Suntech Advanced Ceramics Co ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Shenzhen Suntech Advanced Ceramics Co ltd filed Critical Shenzhen Suntech Advanced Ceramics Co ltd
Priority to CN202010122991.6A priority Critical patent/CN111302777A/en
Publication of CN111302777A publication Critical patent/CN111302777A/en
Pending legal-status Critical Current

Links

Images

Classifications

    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/01—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics
    • C04B35/10—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics based on aluminium oxide
    • C04B35/111—Fine ceramics
    • C04B35/117—Composites
    • C04B35/119—Composites with zirconium oxide
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/01—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics
    • C04B35/48—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics based on zirconium or hafnium oxides, zirconates, zircon or hafnates
    • C04B35/486—Fine ceramics
    • C04B35/488—Composites
    • C04B35/4885—Composites with aluminium oxide
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/622—Forming processes; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/622—Forming processes; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/64—Burning or sintering processes
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
    • F16C17/00—Sliding-contact bearings for exclusively rotary movement
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
    • F16C19/00—Bearings with rolling contact, for exclusively rotary movement
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
    • C04B2235/30—Constituents and secondary phases not being of a fibrous nature
    • C04B2235/32—Metal oxides, mixed metal oxides, or oxide-forming salts thereof, e.g. carbonates, nitrates, (oxy)hydroxides, chlorides
    • C04B2235/3201—Alkali metal oxides or oxide-forming salts thereof
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
    • C04B2235/30—Constituents and secondary phases not being of a fibrous nature
    • C04B2235/32—Metal oxides, mixed metal oxides, or oxide-forming salts thereof, e.g. carbonates, nitrates, (oxy)hydroxides, chlorides
    • C04B2235/3205—Alkaline earth oxides or oxide forming salts thereof, e.g. beryllium oxide
    • C04B2235/3206—Magnesium oxides or oxide-forming salts thereof
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
    • C04B2235/30—Constituents and secondary phases not being of a fibrous nature
    • C04B2235/32—Metal oxides, mixed metal oxides, or oxide-forming salts thereof, e.g. carbonates, nitrates, (oxy)hydroxides, chlorides
    • C04B2235/3205—Alkaline earth oxides or oxide forming salts thereof, e.g. beryllium oxide
    • C04B2235/3208—Calcium oxide or oxide-forming salts thereof, e.g. lime
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
    • C04B2235/30—Constituents and secondary phases not being of a fibrous nature
    • C04B2235/32—Metal oxides, mixed metal oxides, or oxide-forming salts thereof, e.g. carbonates, nitrates, (oxy)hydroxides, chlorides
    • C04B2235/3231—Refractory metal oxides, their mixed metal oxides, or oxide-forming salts thereof
    • C04B2235/3244—Zirconium oxides, zirconates, hafnium oxides, hafnates, or oxide-forming salts thereof
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
    • C04B2235/50—Constituents or additives of the starting mixture chosen for their shape or used because of their shape or their physical appearance
    • C04B2235/54—Particle size related information
    • C04B2235/5418—Particle size related information expressed by the size of the particles or aggregates thereof
    • C04B2235/5445—Particle size related information expressed by the size of the particles or aggregates thereof submicron sized, i.e. from 0,1 to 1 micron
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
    • C04B2235/50—Constituents or additives of the starting mixture chosen for their shape or used because of their shape or their physical appearance
    • C04B2235/54—Particle size related information
    • C04B2235/5418—Particle size related information expressed by the size of the particles or aggregates thereof
    • C04B2235/5454—Particle size related information expressed by the size of the particles or aggregates thereof nanometer sized, i.e. below 100 nm
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/65—Aspects relating to heat treatments of ceramic bodies such as green ceramics or pre-sintered ceramics, e.g. burning, sintering or melting processes
    • C04B2235/656—Aspects relating to heat treatments of ceramic bodies such as green ceramics or pre-sintered ceramics, e.g. burning, sintering or melting processes characterised by specific heating conditions during heat treatment
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/65—Aspects relating to heat treatments of ceramic bodies such as green ceramics or pre-sintered ceramics, e.g. burning, sintering or melting processes
    • C04B2235/656—Aspects relating to heat treatments of ceramic bodies such as green ceramics or pre-sintered ceramics, e.g. burning, sintering or melting processes characterised by specific heating conditions during heat treatment
    • C04B2235/6567—Treatment time
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/65—Aspects relating to heat treatments of ceramic bodies such as green ceramics or pre-sintered ceramics, e.g. burning, sintering or melting processes
    • C04B2235/66—Specific sintering techniques, e.g. centrifugal sintering
    • C04B2235/661—Multi-step sintering
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/70—Aspects relating to sintered or melt-casted ceramic products
    • C04B2235/74—Physical characteristics
    • C04B2235/78—Grain sizes and shapes, product microstructures, e.g. acicular grains, equiaxed grains, platelet-structures
    • C04B2235/785—Submicron sized grains, i.e. from 0,1 to 1 micron
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/70—Aspects relating to sintered or melt-casted ceramic products
    • C04B2235/96—Properties of ceramic products, e.g. mechanical properties such as strength, toughness, wear resistance

Abstract

The invention relates to alumina ceramic, a preparation method thereof and a ceramic bearing. The preparation method of the alumina ceramic comprises the following steps: mixing the raw materials to obtain ceramic powder, wherein the raw materials comprise the following components in percentage by mass: 35 to 99 percent of alumina, 0.5 to 60 percent of zirconia and 0.5 to 5.0 percent of sintering aid, wherein the grain diameter of the raw materials is nano-scale, and the sintering aid comprises magnesium oxide, calcium oxide, sodium oxide, hafnium oxide and potassium oxide; forming the ceramic powder to obtain a ceramic blank; sintering the ceramic blank at 1400-1500 ℃ under normal pressure, and then sintering the ceramic blank at 1300-1350 ℃ under 100-200 MPa under hot isostatic pressure to obtain the alumina ceramic. The preparation method of the alumina ceramic can prepare the alumina ceramic with higher fracture toughness.

Description

Alumina ceramic, preparation method thereof and ceramic bearing
Technical Field
The invention relates to the field of ceramic materials, in particular to alumina ceramic, a preparation method thereof and a ceramic bearing.
Background
The ceramic bearing is widely applied to the fields of various micro motor cooling fans, instruments and meters, office equipment, intelligent homes, household appliances, medical appliances and the like. Because the ceramic bearing has good wear resistance, good chemical corrosion resistance, low density, low thermal expansion coefficient, high elastic modulus and the like, the ceramic bearing has longer service life compared with metal and plastic and is applied in the fields of high-speed bearings, water-cooled heat dissipation bearings and the like.
Alumina has high hardness, high wear resistance and high chemical corrosion resistance, but under the condition of applying external force, the alumina is difficult to slip, thereby showing the disadvantage of lower fracture toughness.
Disclosure of Invention
Accordingly, there is a need for a method for preparing alumina ceramics with high fracture toughness.
In addition, an alumina ceramic and a ceramic bearing are provided.
A preparation method of alumina ceramics comprises the following steps:
mixing the raw materials to obtain ceramic powder, wherein the raw materials comprise the following components in percentage by mass: 35-99% of aluminum oxide, 0.5-60% of zirconium oxide and 0.5-5.0% of sintering aid, wherein the particle size of the raw materials is nano-scale, and the sintering aid comprises magnesium oxide, calcium oxide, sodium oxide, hafnium oxide and potassium oxide;
forming the ceramic powder to obtain a ceramic blank; and
and sintering the ceramic blank at 1400-1500 ℃ under normal pressure, and then sintering the ceramic blank under 1300-1350 ℃ and 100-200 MPa under hot isostatic pressure to obtain the alumina ceramic.
In one embodiment, the average grain size of the alumina is 100nm to 300nm, the average grain size of the zirconia is 10nm to 50nm, and the average grain size of the sintering aid is 100nm to 300 nm.
In one embodiment, the sintering aid comprises, by mass, 0.1% to 1.0% of magnesium oxide, 0.1% to 1.0% of calcium oxide, 0.1% to 1.0% of sodium oxide, 0.1% to 1.0% of hafnium oxide, and 0.1% to 1.0% of potassium oxide, based on the total mass of the raw materials.
In one embodiment, the time of the atmospheric pressure sintering is 2-4 h.
In one embodiment, the hot isostatic pressing sintering time is 1-3 h.
In one embodiment, the step of mixing the raw materials to obtain the ceramic powder includes: mixing the raw materials with zirconia balls and alcohol according to the mass ratio of (1-2) to (2-3) to (1-2), carrying out ball milling for 48-96 h, drying at 60-80 ℃ for 12-24 h, and then sieving with a 300-400 mesh sieve to obtain the ceramic powder.
In one embodiment, in the step of forming the ceramic powder, a cold isostatic pressing or dry pressing manner is adopted.
In one embodiment, after the step of forming the ceramic powder to obtain the ceramic green body, the step of drying and binder removal of the ceramic green body is further included before the step of sintering the ceramic green body at 1400-1500 ℃ under normal pressure.
An alumina ceramic is prepared by the preparation method of the alumina ceramic.
A ceramic bearing is obtained by processing the alumina ceramic.
The alumina ceramic takes nano-scale alumina powder as a matrix and is added with nano ZrO2Is a toughening phase, and improves the mechanical property and the fracture toughness of the alumina. In addition, magnesium oxide, calcium oxide, sodium oxide, hafnium oxide and potassium oxide are added as sintering aids, and the mixed and molded ceramic blank is sintered at the temperature of 1400-1500 ℃ under normal pressure to realize uniform densification of the alumina ceramic and control of the grain size of the alumina, and then sintered under the conditions of 1300-1350 ℃ and 100-200 MPa under hot isostatic pressure to obtain the alumina ceramic with high fracture toughness.
Drawings
Fig. 1 is a process flow diagram of a method for preparing an alumina ceramic according to an embodiment.
Detailed Description
In order that the invention may be more fully understood, reference will now be made to the following description taken in conjunction with the accompanying drawings. The detailed description sets forth the preferred embodiments of the invention. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.
Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.
Referring to fig. 1, a method for preparing an alumina ceramic according to an embodiment includes the following steps:
step S110: mixing the raw materials to obtain ceramic powder, wherein the raw materials comprise the following components in percentage by mass: 35 to 99 percent of alumina, 0.5 to 60 percent of zirconia and 0.5 to 5.0 percent of sintering aid, wherein the grain diameter of the raw materials is nano-scale, and the sintering aid comprises magnesium oxide, calcium oxide, sodium oxide, hafnium oxide and potassium oxide.
Zirconia is distributed in an alumina matrix by adding zirconia, and because the expansion coefficients of the alumina and the zirconia are different, the stress on zirconia particles is relaxed in the sintering and cooling process, and a tetragonal phase is converted into a monoclinic phase to expand the volume, so that microcracks are generated, the effect of toughening the alumina is achieved, and the strength of the alumina ceramic is improved.
The sintering aid can effectively inhibit the growth of crystal grains and improve the uniformity of the crystal grains so as to improve the strength of the ceramic. The particle size of the raw material is set to be in the order of nanometers, which can reduce the crystal grain size of the obtained alumina ceramic and increase the density of the alumina ceramic.
Specifically, the average particle size of alumina is 100nm to 300nm, and the average particle size of zirconia is 10nm to 50 nm. The average grain diameter of the sintering aid is 100 nm-300 nm. When the average particle diameters of alumina, zirconia and the sintering aid are set to the above values, the crystal grain size of the alumina ceramic can be further reduced, and the performance of the alumina ceramic can be improved.
Specifically, the sintering aid comprises, by mass, 0.1-1.0% of magnesium oxide, 0.1-1.0% of calcium oxide, 0.1-1.0% of sodium oxide, 0.1-1.0% of hafnium oxide and 0.1-1.0% of potassium oxide, based on the total mass of the raw materials. The addition of the sintering aid to alumina can lower the sintering temperature and inhibit the growth of crystal grains.
In one embodiment, step S110 includes: mixing the raw materials, a ball milling medium and a solvent according to the mass ratio of (1-2) to (2-3) to (1-2), performing ball milling for 48-96 h, drying at 60-80 ℃ for 12-24 h, and screening by a screen mesh of 300-400 meshes to obtain the ceramic powder.
Wherein, the ball milling medium is zirconia balls. The adoption of zirconia balls as a medium can avoid impurities from being mixed in the raw materials as much as possible. The solvent is alcohol.
The raw materials are ball-milled, dried and sieved, so that the raw materials can be uniformly mixed, and the ceramic powder has uniform particle size, and is beneficial to subsequent forming and sintering.
Further, in some embodiments, the raw materials comprise, by mass percent: 85 to 90 percent of alumina, 0.5 to 20 percent of zirconia and 0.5 to 5.0 percent of sintering aid. According to the total mass of the raw materials, the sintering aid comprises 0.1-1.0% by mass of magnesium oxide, 0.1-1.0% by mass of calcium oxide, 0.1-1.0% by mass of sodium oxide, 0.1-1.0% by mass of hafnium oxide and 0.1-1.0% by mass of potassium oxide.
Step S120: and forming the ceramic powder to obtain a ceramic blank.
Specifically, in step S120, a cold isostatic pressing or dry pressing is adopted. Both hot isostatic pressing and dry pressing may be used as is common in the art.
The obtained ceramic blank has good uniformity by adopting a cold isostatic pressing or dry pressing mode.
Specifically, the method further comprises the steps of drying and removing the adhesive after the step of forming the ceramic powder. In the drying step, the drying temperature is 80-120 ℃. In the step of discharging the rubber, the temperature is 600-800 ℃. The organic reagents such as solvent, binder and the like in the reaction process can be removed through drying and binder removal, so that cracking of the ceramic in the heating sintering process is avoided, and the consistency of ceramic sintering is improved.
Step S130: sintering the ceramic blank at 1400-1500 ℃ under normal pressure, and then sintering the ceramic blank at 1300-1350 ℃ under 100-200 MPa under hot isostatic pressure to obtain the alumina ceramic.
Wherein the time of the normal pressure sintering is 2-4 h. The time of hot isostatic pressing sintering is 1-3 h.
Wherein, in the hot isostatic pressing sintering process, argon or nitrogen is used as a pressurizing medium.
The mode of firstly carrying out normal pressure sintering and then carrying out hot isostatic pressing sintering can control the size of the crystal grains of the aluminum oxide to be uniform and prevent the aluminum oxide from growing abnormally, thereby improving the density of the ceramic.
This factor affects the service life of the ceramic bearing material due to the lower fracture toughness of alumina. Generally, a shaft sleeve in a ceramic bearing requires high hardness, high wear resistance and chemical corrosion resistance, while a ceramic shaft core requires relatively low hardness, but has high toughness, high wear resistance and high surface finish. The general shaft sleeve core combination can be SiC-ZrO2、Al2O3-ZrO2、Al2O3-Si3O4However, when the two are operated at high speed for a long time, the contact surfaces of the two generate heat, so that the difference between the thermal expansion coefficients of the two is large, and the adverse effect of slight noise is generated after the use time is long.
The preparation method of the alumina ceramic at least has the following advantages:
(1) the preparation method of the alumina ceramic takes nano-scale alumina powder as a matrix and adds nano-ZrO2Is a toughening phase, and improves the mechanical property and the fracture toughness of the alumina. In addition, magnesium oxide, calcium oxide, sodium oxide, hafnium oxide and potassium oxide are added as sintering aids, and the ceramic blank after mixing and forming is sintered under normal pressure at 1400-1500 ℃ to realize uniform densification of the alumina ceramic and control of the grain size of the alumina, and then sintered under hot isostatic pressure at 1300-1350 ℃ and 100-200 MPa to obtain the alumina ceramic with high uniformity, high densification, high strength, high hardness and high wear resistance.
(2) The alumina ceramic has high fracture toughness, can be used as a ceramic bearing, and can solve the problem that a shaft sleeve is not matched with a shaft core.
(3) The preparation method of the alumina ceramic has simple process and is easy for industrial production.
An alumina ceramic according to an embodiment is produced by the method for producing an alumina ceramic according to the above embodiment. The alumina ceramic has high density, high strength, high hardness and good wear resistance, and can be used as a ceramic bearing.
A ceramic bearing according to an embodiment is obtained by processing the alumina ceramic according to the above embodiment.
The following are specific examples:
example 1
The preparation process of the alumina ceramic of the embodiment is specifically as follows:
(1) weighing the following raw materials in percentage by mass: 94.5% Al2O3、5.0％ZrO2And 0.5% of sintering aid, wherein the sintering aid is 0.1% of MgO, 0.1% of CaO and 0.1% of Na2O、0.1％Hf2O and 0.1% K2A mixture of O. Then mixing the raw materials with zirconia balls and alcohol according to the mass ratio of 1: 2: 1, wet-grinding in a high-energy ball mill for 48h, drying at 60 ℃ for 24h, and then sieving by a 300-mesh sieve to obtain the ceramic powder.
(2) And (3) carrying out cold isostatic pressing on the ceramic powder, drying at 100 ℃, and discharging glue at 700 ℃ to obtain a ceramic blank.
(3) Firstly, sintering the ceramic blank at 1400 ℃ under normal pressure for 2h, then carrying out hot isostatic pressing sintering at 1350 ℃ and 100MPa for 1h by taking nitrogen as a pressurizing medium to obtain the alumina ceramic.
Example 2
The preparation process of the alumina ceramic of the embodiment is specifically as follows:
(1) weighing the following raw materials in percentage by mass: 35% Al2O3、60％ZrO2And 5.0% of sintering aid, wherein the sintering aid is 1.0% of MgO, 1.0% of CaO and 1.0% of Na2O、1.0％Hf2O and 1.0% K2A mixture of O. Then mixing the raw materials with zirconia balls and alcohol according to the mass ratio of 1: 2: 1, wet-grinding in a high-energy ball mill for 48h, drying at 60 ℃ for 24h, and then sieving by a 300-mesh sieve to obtain the ceramic powder.
(2) And (3) carrying out cold isostatic pressing on the ceramic powder, drying at 100 ℃, and discharging glue at 700 ℃ to obtain a ceramic blank.
(3) Firstly, sintering the ceramic blank at 1400 ℃ under normal pressure for 2h, then carrying out hot isostatic pressing sintering at 1350 ℃ and 100MPa for 1h by taking nitrogen as a pressurizing medium to obtain the alumina ceramic.
Example 3
The preparation process of the alumina ceramic of the embodiment is specifically as follows:
(1) weighing the following raw materials in percentage by mass: 99% Al2O3、0.5％ZrO2And 0.5% of sintering aid, wherein the sintering aid is 0.1% of MgO, 0.1% of CaO and 0.1% of Na2O、0.1％Hf2O and 0.1% K2A mixture of O. Then mixing the raw materials with zirconia balls and alcohol according to the mass ratio of 2: 3: 2, wet-grinding for 72h in a high-energy ball mill, drying for 18h at 70 ℃, and then sieving with a 350-mesh sieve to obtain the ceramic powder.
(2) And (3) carrying out cold isostatic pressing on the ceramic powder, drying at 120 ℃, and discharging glue at 800 ℃ to obtain a ceramic blank.
(3) Firstly, sintering the ceramic blank at 1450 ℃ under normal pressure for 3h, then carrying out hot isostatic pressing sintering for 2h at 1325 ℃ and 150MPa by taking nitrogen as a pressurizing medium to obtain the alumina ceramic.
Example 4
The preparation process of the alumina ceramic of the embodiment is specifically as follows:
(1) weighing the following raw materials in percentage by mass: 70% Al2O3、28％ZrO2And 2% of sintering aid, wherein the sintering aid is 0.4% of MgO, 0.4% of CaO and 0.4% of Na2O、0.4％Hf2O and 0.4% K2A mixture of O. Then mixing the raw materials with zirconia balls and alcohol according to the mass ratio of 1.5: 2.5: 1.5, wet-grinding for 96h in a high-energy ball mill, drying for 12h at 80 ℃, and then sieving by a 400-mesh sieve to obtain the ceramic powder.
(2) And (3) carrying out dry pressing molding on the ceramic powder, and then drying at 80 ℃ and carrying out degumming at 600 ℃ to obtain a ceramic blank.
(3) Firstly, sintering the ceramic blank at 1500 ℃ under normal pressure for 4h, then carrying out hot isostatic pressing sintering at 1300 ℃ and 200MPa for 3h by taking argon as a pressurizing medium to obtain the alumina ceramic.
Example 5
The alumina ceramic of this example was prepared in a similar manner to the alumina ceramic of example 1, except that: in the step (1), the raw materials are as follows by mass percent: 88% Al2O3、11％ZrO2And 1% of sintering aid, wherein the sintering aid is 0.2% of MgO, 0.2% of CaO and 0.2% of Na2O、0.2％Hf2O and 0.2% K2A mixture of O.
Comparative example 1
The alumina ceramic of comparative example 1 was prepared in a similar manner to the alumina ceramic of example 1 except that: in the step (1), the raw materials are as follows by mass percent: 35% Al2O3、58％ZrO2And 7.0% of sintering aid, wherein the sintering aid is 1.4% of MgO, 1.4% of CaO and 1.4% of Na2O、1.4％Hf2O and 1.4% K2Of OAnd (3) mixing.
Comparative example 2
The alumina ceramic of comparative example 2 was prepared in a similar manner to the alumina ceramic of example 1, except that: in the step (1), the raw materials are as follows by mass percent: 95% Al2O3And 5.0% of sintering aid, wherein the sintering aid is 1.0% of MgO, 1.0% of CaO and 1.0% of Na2O、1.0％Hf2O and 1.0% K2A mixture of O.
Comparative example 3
The alumina ceramic of comparative example 3 was prepared in a similar manner to the alumina ceramic of example 1, except that: in the step (1), the raw materials are as follows by mass percent: 94.5% Al2O3、5.0％ZrO2And 0.5% of sintering aid, wherein the sintering aid is 0.1% of MgO, 0.1% of CaO and 0.2% of Na2O and 0.1% Hf2A mixture of O.
Comparative example 4
The alumina ceramic of comparative example 4 was prepared in a similar manner to the alumina ceramic of example 1, except that: in the step (1), the raw materials comprise the following components in percentage by mass: 94.5% Al2O3、5.0％ZrO2And 0.5% of sintering aid, wherein the sintering aid is 0.2% of CaO and 0.1% of Na2O、0.1％Hf2O and 0.1% K2A mixture of O.
Comparative example 5
The alumina ceramic of comparative example 5 was prepared in a similar manner to the alumina ceramic of example 1, except that: in the step (3), the pressure of hot isostatic pressing sintering is 50 MPa.
Comparative example 6
The alumina ceramic of comparative example 6 was prepared in a similar manner to the alumina ceramic of example 1, except that: in the step (3), the pressure of hot isostatic pressing sintering is 250 MPa.
Comparative example 7
The alumina ceramic of comparative example 7 was prepared in a similar manner to the alumina ceramic of example 1, except that: in the step (3), the time of normal pressure sintering is 1h, and the time of hot isostatic pressing sintering is 4 h.
Comparative example 8
The alumina ceramic of comparative example 8 was prepared in a similar manner to the alumina ceramic of example 1, except that: in the step (3), the time of normal pressure sintering is 5 hours, and the time of hot isostatic pressing sintering is 0.5 hour.
Comparative example 9
The alumina ceramic of comparative example 9 was prepared in a similar manner to the alumina ceramic of example 1, except that: in the step (3), only normal pressure sintering is carried out, and hot isostatic pressing sintering is not carried out.
Comparative example 10
The alumina ceramic of comparative example 10 was prepared in a similar manner to the alumina ceramic of example 1, except that: in the step (3), hot isostatic pressing sintering is only carried out, and normal pressure sintering is not carried out.
Comparative example 11
The alumina ceramic of comparative example 11 was prepared in a similar manner to the alumina ceramic of example 1 except that: in the step (3), the temperature of the normal pressure sintering is 1300 ℃, and the temperature of the hot isostatic pressing sintering is 1400 ℃.
Comparative example 12
The alumina ceramic of comparative example 12 was prepared in a similar manner to the alumina ceramic of example 1, except that: in the step (3), the temperature of normal pressure sintering is 1600 ℃, and the temperature of hot isostatic pressing sintering is 1200 ℃.
The compactness of the alumina ceramic powder materials of examples 1 to 5 and comparative examples 1 to 12 was tested by GB-T25995-2010 Archimedes drainage method. The grain sizes of the alumina ceramics of examples 1 to 5 and comparative examples 1 to 12 were measured by scanning electron microscopy. The alumina ceramics of examples 1 to 5 and comparative examples 1 to 12 were tested for hardness using astm e384-17 nanoindentation method. The alumina ceramics of examples 1 to 5 and comparative examples 1 to 12 were tested for strength by GBT6065-2006 three-point bending strength method. The alumina ceramics of examples 1 to 5 and comparative examples 1 to 12 were tested for fracture toughness using the single-edge notched beam method. The wear resistance of the alumina ceramics of examples 1 to 5 and comparative examples 1 to 12 was tested by JC/T2345-2015 precision ceramics normal temperature wear test method, and the experimental data shown in Table 1 were obtained.
TABLE 1 Experimental data for alumina ceramics of examples 1 to 5 and comparative examples 1 to 12
Figure BDA0002392553680000111
As can be seen from Table 1 above, the alumina ceramics prepared in examples 1-5 have a density of 95% or more, even up to 99%, smaller grain size of 0.7-0.8 μm, and microhardness of 1300 HV-1900 HV. In addition, the fracture toughness of the alumina ceramic is 5.4MPa1/2～8.0MPa.m1/2Meanwhile, the abrasion quality is only 0.001 g-0.002 g, and the abrasion resistance is better. Therefore, the alumina ceramics prepared in examples 1 to 5 have good fracture toughness and good wear resistance, and can be processed into ceramic bearings.
The alumina ceramics prepared in the above example 1 and comparative example 1 were respectively processed into ceramic bearings, which are denoted as example 1 bearing and comparative example 1 bearing, and the two bearings were operated for 1000 hours under the same conditions, and whether noise occurred during the operation of the two bearings and the wear of the two bearings after the operation were observed, to obtain the experimental results shown in the following table 2.
TABLE 2 conditions during operation of the bearing of example 1 and the bearing of comparative example 1
Figure BDA0002392553680000121
As can be seen from Table 2, the bearings made from the alumina ceramic of example 1 were noiseless during operation, had lower wear and had longer service life.
The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.
The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.

Claims (10)

1. The preparation method of the alumina ceramic is characterized by comprising the following steps:
mixing the raw materials to obtain ceramic powder, wherein the raw materials comprise the following components in percentage by mass: 35-99% of aluminum oxide, 0.5-60% of zirconium oxide and 0.5-5.0% of sintering aid, wherein the particle size of the raw materials is nano-scale, and the sintering aid comprises magnesium oxide, calcium oxide, sodium oxide, hafnium oxide and potassium oxide;
forming the ceramic powder to obtain a ceramic blank; and
and sintering the ceramic blank at 1400-1500 ℃ under normal pressure, and then sintering the ceramic blank under 1300-1350 ℃ and 100-200 MPa under hot isostatic pressure to obtain the alumina ceramic.
2. The method of producing an alumina ceramic according to claim 1, wherein the average particle size of the alumina is 100 to 300nm, the average particle size of the zirconia is 10 to 50nm, and the average particle size of the sintering aid is 100 to 300 nm.
3. The method for preparing the alumina ceramic according to claim 1, wherein the sintering aid comprises, based on the total mass of the raw materials, 0.1 to 1.0 mass% of magnesium oxide, 0.1 to 1.0 mass% of calcium oxide, 0.1 to 1.0 mass% of sodium oxide, 0.1 to 1.0 mass% of hafnium oxide, and 0.1 to 1.0 mass% of potassium oxide.
4. The method for preparing alumina ceramics according to claim 1, wherein the time of the atmospheric sintering is 2 to 4 hours.
5. The method of claim 1, wherein the hot isostatic pressing sintering is performed for a period of 1 to 3 hours.
6. The method of claim 1, wherein the step of mixing the raw materials to obtain the ceramic powder comprises: mixing the raw materials with zirconia balls and alcohol according to the mass ratio of (1-2) to (2-3) to (1-2), carrying out ball milling for 48-96 h, drying at 60-80 ℃ for 12-24 h, and then sieving with a 300-400 mesh sieve to obtain the ceramic powder.
7. The method according to claim 1, wherein the step of forming the ceramic powder is performed by cold isostatic pressing or dry pressing.
8. The method for preparing the alumina ceramic according to claim 1, wherein after the step of forming the ceramic powder to obtain the ceramic body, the step of drying and binder removal of the ceramic body is further included before the step of sintering the ceramic body at 1400 ℃ to 1500 ℃ under normal pressure.
9. An alumina ceramic produced by the method for producing an alumina ceramic according to any one of claims 1 to 8.
10. A ceramic bearing obtained by processing the alumina ceramic according to claim 9.
CN202010122991.6A 2020-02-26 2020-02-26 Alumina ceramic, preparation method thereof and ceramic bearing Pending CN111302777A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202010122991.6A CN111302777A (en) 2020-02-26 2020-02-26 Alumina ceramic, preparation method thereof and ceramic bearing

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202010122991.6A CN111302777A (en) 2020-02-26 2020-02-26 Alumina ceramic, preparation method thereof and ceramic bearing

Publications (1)

Publication Number Publication Date
CN111302777A true CN111302777A (en) 2020-06-19

Family

ID=71154724

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202010122991.6A Pending CN111302777A (en) 2020-02-26 2020-02-26 Alumina ceramic, preparation method thereof and ceramic bearing

Country Status (1)

Country Link
CN (1) CN111302777A (en)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112250427A (en) * 2020-10-21 2021-01-22 苏州晶瓷超硬材料有限公司 Sintering process of high-purity silicon oxide ceramic
CN112250426A (en) * 2020-10-21 2021-01-22 苏州晶瓷超硬材料有限公司 High-purity alumina ceramic and preparation method thereof
CN112624793A (en) * 2021-01-08 2021-04-09 罗焕焕 Preparation method of alumina-based porous ceramic material
CN115448742A (en) * 2022-08-29 2022-12-09 湖南圣瓷科技有限公司 Aluminum oxide anti-static ceramic and preparation method thereof
CN115819070A (en) * 2022-11-16 2023-03-21 深圳市爱斯强科技有限公司 Ceramic slurry and ceramic matrix

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4285732A (en) * 1980-03-11 1981-08-25 General Electric Company Alumina ceramic
JPH07187759A (en) * 1993-12-27 1995-07-25 Shinagawa Refract Co Ltd Alumina ceramics and its production
US20120096822A1 (en) * 2009-06-26 2012-04-26 Saint-Gobain Centre De Rech. Et D'etudes Europeen Fused grains of oxides comprising al, ti, si and ceramic products comprising such grains
CN109485393A (en) * 2018-11-28 2019-03-19 深圳市商德先进陶瓷股份有限公司 Aluminium oxide ceramics and preparation method thereof and ceramic chopper
CN110105057A (en) * 2019-06-26 2019-08-09 深圳市商德先进陶瓷股份有限公司 Ceramic arm and preparation method thereof, vacuum suction machinery hand and wafer conveying device

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4285732A (en) * 1980-03-11 1981-08-25 General Electric Company Alumina ceramic
JPH07187759A (en) * 1993-12-27 1995-07-25 Shinagawa Refract Co Ltd Alumina ceramics and its production
US20120096822A1 (en) * 2009-06-26 2012-04-26 Saint-Gobain Centre De Rech. Et D'etudes Europeen Fused grains of oxides comprising al, ti, si and ceramic products comprising such grains
CN109485393A (en) * 2018-11-28 2019-03-19 深圳市商德先进陶瓷股份有限公司 Aluminium oxide ceramics and preparation method thereof and ceramic chopper
CN110105057A (en) * 2019-06-26 2019-08-09 深圳市商德先进陶瓷股份有限公司 Ceramic arm and preparation method thereof, vacuum suction machinery hand and wafer conveying device

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
王德平 等: "《无机材料结构与性能》", 31 August 2015, 同济大学出版社 *

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112250427A (en) * 2020-10-21 2021-01-22 苏州晶瓷超硬材料有限公司 Sintering process of high-purity silicon oxide ceramic
CN112250426A (en) * 2020-10-21 2021-01-22 苏州晶瓷超硬材料有限公司 High-purity alumina ceramic and preparation method thereof
CN112624793A (en) * 2021-01-08 2021-04-09 罗焕焕 Preparation method of alumina-based porous ceramic material
CN115448742A (en) * 2022-08-29 2022-12-09 湖南圣瓷科技有限公司 Aluminum oxide anti-static ceramic and preparation method thereof
CN115448742B (en) * 2022-08-29 2024-03-29 湖南圣瓷科技有限公司 Alumina antistatic ceramic and preparation method thereof
CN115819070A (en) * 2022-11-16 2023-03-21 深圳市爱斯强科技有限公司 Ceramic slurry and ceramic matrix
CN115819070B (en) * 2022-11-16 2023-12-19 深圳市爱斯强科技有限公司 Ceramic slurry and ceramic matrix

Similar Documents

Publication Publication Date Title
CN111302777A (en) Alumina ceramic, preparation method thereof and ceramic bearing
Vasylkiv et al. Low‐temperature processing and mechanical properties of zirconia and zirconia–alumina nanoceramics
JP5367080B2 (en) Large ceramic rolling element
JP6637956B2 (en) Sintered ceramic material, powder composition for obtaining sintered ceramic material, method for producing the same, and ceramic component
CN106915961B (en) Graphene-zirconia composite material and preparation method thereof
JP2008050247A (en) Sintered zirconia having high strength and process for production thereof
CN110330318A (en) A kind of micro-nano composite ceramic tool material and preparation method thereof
CN110105057A (en) Ceramic arm and preparation method thereof, vacuum suction machinery hand and wafer conveying device
CN108585911B (en) Alumina ceramic and preparation method and application thereof
CN1673173A (en) Nano crystal adding alumina ceramic material and its low temperature liquid phase sintering process
CN109020508B (en) Three-dimensional graphene bridged oxide ceramic and preparation method thereof
KR101793031B1 (en) Manufacturing method of alumina-graphene composites with excellent wear resistance
Ni et al. Textured HfB2-based ultrahigh-temperature ceramics with anisotropic oxidation behavior
JP2008019144A (en) Manufacturing method of ceramic composite material containing zirconia
JP5362758B2 (en) Wear resistant parts
CN108658589A (en) The preparation method of sub-micro crystal alumina ceramic tool matrix material
CN107793138A (en) A kind of aluminium oxide ceramics
CN108329018A (en) A kind of toughened aluminum oxide composite ceramics and preparation method thereof
JP5854503B2 (en) Nanocomposite material and method for producing nanocomposite material
CN113105216A (en) Injection-molded zirconium-aluminum composite ceramic and preparation method thereof
CN108358628B (en) Mullite-zirconia composite ceramic and preparation method thereof
JP2008156169A (en) Silicon carbide granule, method for producing silicon carbide sintered compact using it and silicon carbide sintered compact
JP2001019538A (en) Alumina-based composite ceramic and its production
CN114644513B (en) Preparation method of mullite infrared transparent ceramic
JPH10194823A (en) Magnesium oxide composite ceramics and its production

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
RJ01 Rejection of invention patent application after publication

Application publication date: 20200619

RJ01 Rejection of invention patent application after publication