CN111646782A - ZTA ceramic material, heating element and preparation method thereof - Google Patents
ZTA ceramic material, heating element and preparation method thereof Download PDFInfo
- Publication number
- CN111646782A CN111646782A CN202010508689.4A CN202010508689A CN111646782A CN 111646782 A CN111646782 A CN 111646782A CN 202010508689 A CN202010508689 A CN 202010508689A CN 111646782 A CN111646782 A CN 111646782A
- Authority
- CN
- China
- Prior art keywords
- zirconia
- powder
- alumina
- sintering
- zta ceramic
- 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
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
-
- 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
- C04B35/626—Preparing or treating the powders individually or as batches ; preparing or treating macroscopic reinforcing agents for ceramic products, e.g. fibres; mechanical aspects section B
- C04B35/63—Preparing or treating the powders individually or as batches ; preparing or treating macroscopic reinforcing agents for ceramic products, e.g. fibres; mechanical aspects section B using additives specially adapted for forming the products, e.g.. binder binders
- C04B35/632—Organic additives
-
- 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
- C04B35/626—Preparing or treating the powders individually or as batches ; preparing or treating macroscopic reinforcing agents for ceramic products, e.g. fibres; mechanical aspects section B
- C04B35/63—Preparing or treating the powders individually or as batches ; preparing or treating macroscopic reinforcing agents for ceramic products, e.g. fibres; mechanical aspects section B using additives specially adapted for forming the products, e.g.. binder binders
- C04B35/632—Organic additives
- C04B35/634—Polymers
- C04B35/63404—Polymers obtained by reactions only involving carbon-to-carbon unsaturated bonds
- C04B35/6342—Polyvinylacetals, e.g. polyvinylbutyral [PVB]
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
- H05B3/00—Ohmic-resistance heating
- H05B3/20—Heating elements having extended surface area substantially in a two-dimensional plane, e.g. plate-heater
- H05B3/22—Heating elements having extended surface area substantially in a two-dimensional plane, e.g. plate-heater non-flexible
- H05B3/28—Heating elements having extended surface area substantially in a two-dimensional plane, e.g. plate-heater non-flexible heating conductor embedded in insulating material
- H05B3/286—Heating elements having extended surface area substantially in a two-dimensional plane, e.g. plate-heater non-flexible heating conductor embedded in insulating material the insulating material being an organic material, e.g. plastic
-
- 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
- C04B2235/70—Aspects relating to sintered or melt-casted ceramic products
- C04B2235/74—Physical characteristics
- C04B2235/77—Density
-
- 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
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Ceramic Engineering (AREA)
- Manufacturing & Machinery (AREA)
- Materials Engineering (AREA)
- Structural Engineering (AREA)
- Organic Chemistry (AREA)
- Inorganic Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Compositions Of Oxide Ceramics (AREA)
Abstract
The invention relates to a ZTA ceramic material, a heating element and a preparation method thereof, wherein the ZTA ceramic material is formed by sintering a composition containing powder, and the powder consists of the following components in percentage by volume: 88 to 96 percent of alumina powder; 4 to 12 percent of zirconia powder; the grain size ratio of the alumina to the zirconia after sintering is 2.380 to 4.444. The ZTA ceramic material of the invention takes alumina and zirconia as main materials, and the use ratio of the alumina to the zirconia and the grain size ratio are adjusted, thereby not only ensuring the function of the zirconia as a toughening phase, but also avoiding the problem of leakage current, and improving the use temperature of the ZTA ceramic heating material.
Description
Technical Field
The invention relates to the technical field of ZTA ceramics, in particular to a ZTA ceramic material, a heating element and a preparation method thereof.
Background
ZTA (zirconia Toughened alumina) ceramic is Al2O3As a matrix, partially stabilized ZrO2Is a complex phase ceramic material of toughening phase. The mechanical property of ZTA ceramic is between that of Al2O3Ceramics and ZrO2Between the ceramics, not only Al is reserved2O3High hardness and wear resistance of ceramics, and ZrO2The ceramic has the advantages of good fracture toughness and high bending strength, and the price is lower than that of ZrO2A ceramic. Because the ZTA ceramic has excellent heat radiation property, thermal shock resistance and mechanical strength, the ZTA ceramic is often used as a structural ceramic with high strength, and the ZTA ceramic copper-clad substrate and the heating element are widely applied to a pressure sensor, an electric automobile IGBT, a DC-AC inverter and an electronic cigarette.
However, ZrO2The ZTA ceramic is used as a toughening phase and is also a conductive phase. When ZrO2When the content exceeds a certain amount, the ZTA ceramic copper-clad circuit board has leakage current, and the heating element can be punctured when applied, so that the product fails.
Disclosure of Invention
In view of the defects of the prior art, the first object of the invention is to provide a ZTA ceramic material, and the second object of the invention is to provide a ZTA ceramic heating element, wherein the ceramic material and the heating element can improve the breakdown phenomenon, so that the ZTA ceramic can meet the use requirements of a copper-clad circuit board and a heating element with the limiting temperature of 600 ℃ while obtaining high strength. The third purpose of the invention is to provide a preparation method of the ZTA ceramic material, which is used for preparing the ZTA ceramic material or the ZTA heating element.
In order to achieve the first object of the invention, the invention provides a ZTA ceramic material which is sintered by a composition containing powder, wherein the powder consists of the following components in percentage by volume: 88 to 96 percent of alumina powder; 4 to 12 percent of zirconia powder; the grain size ratio of the alumina to the zirconia after sintering is 2.380 to 4.444.
Therefore, the ZTA ceramic material of the invention takes alumina and zirconia as main materials, and the function of zirconia as toughening phase is ensured without generating leakage current by adjusting the dosage ratio of the alumina and the zirconia and the grain size ratio, thereby improving the use temperature of the ZTA ceramic heating material. The particle size of the alumina powder and the zirconia powder can be properly selected according to the grain size ratio.
The further technical scheme is that the volume fraction of the alumina powder is 91-92%, and the volume fraction of the zirconia powder is 8-9%. The further technical proposal is that the volume fraction of the alumina powder is 91.43 percent, and the volume fraction of the zirconia powder is 8.57 percent. The alumina powder or zirconia powder is mixed powder formed by mixing two kinds of powder with different average grain diameters; in the mixed powder, the first part volume ratio of the alumina-to-zirconia grain size ratio of 2.380 to 2.415 was 1/3, and the second part volume ratio of the alumina-to-zirconia grain size ratio of 4.380 to 4.444 was 2/3.
From the above, the present invention further defines the amount ratio and the grain size ratio of alumina and zirconia, for example, in the volume fraction of zirconia of 8.57%, so that the volume fraction of zirconia in the 0.414 portion of the grain size ratio of zirconia to alumina is 1/3, the volume fraction of zirconia in this portion is 2.86%, and the volume fraction of zirconia in the 0.225 portion of the grain size ratio is 5.71%. When the dosage proportion and the grain diameter ratio are in the range, the method is favorable for realizing the closest packing of cubic packing arrangement of alumina particles and zirconia particles and the filling of different gaps in ZTA ceramics, ensures the high strength of the material, improves the problem of breakdown leakage and improves the high-temperature volume resistance of the ceramic material.
The technical scheme is that the composition also comprises a solvent, a dispersant, a plasticizer and a bonding agent, and the ZTA ceramic material is formed by casting and sintering the composition.
From the above, the composition for preparing the ceramic material of the present invention further comprises other auxiliary components, wherein the solvent is used as a dispersion medium of the material; the dispersing agent is used for improving the ball milling dispersing efficiency of the main material and increasing the dispersing uniformity of the powder; the plasticizer provides flexibility to the molded blank; the binder provides rigidity to the formed green body, preventing deformation of the green body.
The technical scheme is that the mass of the adhesive is 8.0-9.0%, the mass of the dispersing agent is 0.5-0.7%, the mass of the plasticizer is 4.0-4.5%, and the mass of the solvent is 25-30% relative to 100% of the mass of the powder.
Therefore, when the auxiliary components in the composition are in the dosage range, the requirements on dispersion and green body performance can be well met, and the performance of a final sintered body is not influenced.
The further technical proposal is that the alumina is alpha-alumina.
Therefore, alpha-alumina is preferred as the alumina in the invention, and the alpha-alumina has the characteristics of stable crystal form, narrow particle size distribution range, higher purity, lower specific surface area and the like, and is beneficial to improving the performance of the ZTA ceramic material.
The further technical proposal is that the zirconia is 3Y zirconia.
As can be seen from the above, the zirconia in the present invention is preferably 3Y zirconia, i.e. 3 mol% yttria partially stabilized zirconia, and yttria can change the phase transition temperature range of zirconia, so that the crystal phase of zirconia is more stable.
The further technical scheme is that the solvent is absolute ethyl alcohol and trichloroethylene according to the mass ratio of 27: 73 or a binary azeotropic mixture of absolute ethyl alcohol and butanone as the solvent.
As can be seen from the above, the present invention preferably uses the above-mentioned azeotropic mixture as a dispersion medium for the powder, the above-mentioned azeotropic mixture can disperse the powder well, and the dispersion medium is easy to burn off, and does not affect the properties of the final sintered body.
The further technical scheme is that the dispersing agent is phosphate ester.
As can be seen from the above, the dispersant is preferably a phosphate, such as castor oil phosphate, and the phosphate dispersant is one of the dispersants that have the best dispersion effect for alumina ceramic slurry, and the phosphate dispersant is combined with the above polar non-aqueous solvent to well prevent the flocculation of the powder.
The further technical proposal is that the adhesive is polyvinyl butyral.
As can be seen from the above, the binder is preferably polyvinyl butyral, which has stable properties, no residue after burning out, and can stabilize slurry.
The further technical proposal is that the plasticizer is phthalate.
As can be seen, the plasticizer is preferably a phthalate ester, such as octyl phthalate or dibutyl phthalate, which can provide efficient plasticization and which, in combination with the polyvinyl butyral binder, does not reduce the strength of the green body too much.
In order to achieve the second object of the present invention, the present invention provides a ZTA ceramic heating element comprising one of the ZTA ceramic materials according to any one of the above aspects and a heating resistor, wherein the ZTA ceramic heating element is formed by co-firing the heating resistor at a high temperature after printing the heating resistor on the composition before sintering the composition.
Therefore, the invention provides a heating element comprising the ceramic material, and the heating element enables the heating resistor and the ceramic material to be integrally formed through co-firing. The heating element has good mechanical property, can work at the limit temperature of 600 ℃, and meets the requirements of volume resistivity and the like of the ceramic substrate at normal temperature and high temperature of 600 ℃.
The further technical scheme is that the heating resistor is tungsten, and high-temperature co-firing is carried out at 1500-1650 ℃ in a reducing atmosphere; or the heating resistor is platinum, and the high-temperature co-firing is carried out in an oxidizing atmosphere of 1500-1650 ℃.
Therefore, the invention further defines the co-firing conditions of different heating resistors, and the heating resistors are formed while the ZTA ceramic is formed by co-firing.
In order to achieve the third object of the invention, the invention provides a preparation method of a ZTA ceramic material, which comprises the following steps of: 88 to 96 percent of alumina and 4 to 12 percent of zirconia; preparing the following auxiliary components in percentage by mass based on 100% of the mass of the powder: 25 to 30 percent of solvent, 0.5 to 0.7 percent of dispersant, 4.0 to 4.5 percent of plasticizer and 8.0 to 9.0 percent of adhesive; and performing the following steps: the method comprises the following steps: grinding and dispersing alumina, zirconia, a dispersant and a part of solvent; step two: adding the plasticizer, the binder and the residual solvent, and continuously grinding and dispersing; step three: defoaming; step four: homogenizing; step five: tape casting; step six: drying, collecting, aging and homogenizing; step seven: sintering and forming, wherein the grain size ratio of the sintered alumina to the sintered zirconia is 2.380 to 4.444.
Therefore, the powder can be fully dispersed by adopting the adding sequence, and the powder is fully mixed with the dispersing agent and then fully mixed with the plasticizer and the binder, so that the uniformity of the formed green body is ensured. The invention eliminates the bubbles in the slurry through defoaming, and improves the defoaming effect through homogenization, so that the formed green body has no air hole or pinhole defect, thereby improving the product quality. The invention also improves the consistency of the green body performance by aging and homogenizing under certain humidity and temperature, reduces the defects in the sintering process, and particularly can reduce the warpage and deformation. The types and the amounts of the alumina, the zirconia, the solvent, the dispersant, the plasticizer and the adhesive can be the same as those described in the technical scheme of the ZTA ceramic material.
The further technical scheme is that the first step and the second step are carried out in a ball mill, and the grinding time of the first step and the grinding time of the second step are respectively 24-48 h.
Therefore, the invention disperses the materials by the ball mill, thereby fully dispersing the powder in the step one and uniformly dispersing all the components in the step two.
And the third step is carried out in a defoaming machine, defoaming is carried out for 25min to 40min under the condition that the negative pressure is lower than-0.085 MPa, and casting slurry with the viscosity of 20000mPa s to 24000mPa s is obtained. The further technical scheme is that the fourth step is carried out in a defoaming machine, the negative pressure is kept, and the homogenization is carried out for 0.5 to 2 hours at the rotating speed of 3 to 6 r/min.
Therefore, the invention carries out defoaming and homogenizing under certain negative pressure, so that the effect of eliminating bubbles is better.
The further technical scheme is that the fifth step is casting molding on a casting machine.
Therefore, the casting machine is preferably adopted to prepare the green body, the generation process is simple, the cost is low, and batch generation can be realized.
The further technical scheme is that in the sixth step, the ageing and homogenizing are carried out for more than 8 hours.
From the above, the present invention further defines the time of staling homogenization, within which the green components can be further stabilized.
The seventh technical scheme is that the step seven is pressureless sintering in a high-temperature kiln at 1500-1650 ℃ for 3-6 h. The further technical proposal is that the sintering temperature of the seventh step is 1600 ℃ to 1630 ℃.
Therefore, the invention further limits the sintering time and temperature, and can completely remove auxiliary components such as solvent, dispersant, adhesive and the like in the temperature and time range, thereby improving the performance of the sintered product.
The further technical scheme is that the punching method further comprises the following step between the sixth step and the seventh step: and die cutting the green body obtained in the sixth step to a required size.
From the above, the present invention can also die cut the green body before sintering to obtain the required dimensions, for example, die cut green body to finally sinter into a ceramic substrate of 138 × 190 × 0.32mm specification.
The further technical scheme is that the method also comprises the following steps between the sixth step and the seventh step: printing a heating resistor on the green body obtained in the step six, covering a green body for lamination, and then carrying out isostatic pressing treatment; and step seven, co-firing at high temperature to obtain the ZTA ceramic heating element.
Therefore, the heating resistor can be printed on the green body, and the green body of the heating element can be obtained by isostatic pressing after lamination. Specifically, for example, one sheet of an equal-sized green sheet may be covered and laminated, and hot water isostatic pressing may be performed with 95 ℃ hot water.
Drawings
FIG. 1 is a field emission scanning electron micrograph of (a) a cast green body and (b) a sintered ceramic substrate of example 2 of the present invention.
FIG. 2 is a graph showing the results of an energization test in examples of the present invention and comparative examples, in which FIG. 2(a) shows a ZTA ceramic heat generating sheet of 16.1% zirconia after heating for 60 seconds, FIG. 2(b) shows a ZTA ceramic heat generating sheet of 16.1% zirconia after cooling, FIG. 2(c) shows a ZTA ceramic heat generating sheet of 8.57% zirconia after heating for 60 seconds, and FIG. 2(d) shows a ZTA ceramic heat generating sheet of 8.57% zirconia after cooling.
FIG. 3 is a temperature resistance curve diagram of a ZTA ceramic exothermic sheet containing 8.57% zirconia according to the embodiment of the present invention.
FIG. 4 is a graph showing the surface temperature of a ZTA ceramic exothermic sheet having a zirconia content of 8.57% with time according to the example of the present invention.
The present invention will be described in further detail with reference to the accompanying drawings and specific embodiments.
Detailed Description
The invention is based on the following theoretical basis:
in ZTA ceramics, alumina crystal grain is insulating phase, zirconia crystal grain is conducting phase, in its microstructure, if the conducting phase is distributed in isolated form, the resistivity of the material is large; if the conductive phase is distributed continuously, the resistivity of the material is small. The conductive performance of the conductive ceramic is positively correlated with the volume fraction of the conductive phase in the material. The ceramic powder has high surface free energy, and under the action of high temperature, the excessive surface energy of the powder becomes sintering power, so that the powder grows into a polyhedral crystal combination with the smallest surface energy. In accordance with the principle of minimizing surface energy, in an ideal situation, the microstructure of the ZTA ceramic after sintering should resemble the weier-fran model. When preparing ZTA ceramic, the alumina powder is assumed to be spherical, and the diameter thereof is Da(ii) a The zirconia powder is also spherical and has a diameter Dz. Completely and uniformly mixing the alumina powder and the zirconia powder, and carrying out tape casting until sintering is finished, wherein the volume fraction V of the zirconia particles is assumedzNo change occurred. After sintering, alumina grains grow into a tetradecahedron, and zirconia grains grow into a dodecahedron. According to the weil-fran model, there are 2 grains of alumina and 6 grains of zirconia in one basic unit. Then in the ZTA ceramic, the volume fraction of zirconia grains is as shown in formula (1):
after simplification of formula (1), formula (2) can be obtained:
when D is presenta/DzWhen the volume fraction is 2.5, the inflection point is the inflection point of the change of the volume fraction of zirconia, and the volume fraction V isz16.1%. However, the ZTA ceramic substrate with the zirconia content of 16.1 percent is directly coated with copper to be made into a success rate device, the device generates heat during high-power test, the leakage current between ceramic copper-coated circuits appears, and the volume resistivity is lower than the national standard requirement at 300 ℃.
Therefore, the optimal volume fraction of zirconia in ZTA ceramic substrates was further calculated according to the cubic arrangement principle. The stable ion arrangement in the crystal structure is the lowest energy state, the cubic arrangement is the stable structure with the largest bulk density, and the bulk density reaches 74 vol%. Each layer of balls is in the form of a cube, with the upper layer being placed over the voids of the lower layer to form a close-packed structure. Each ball has 12 nearest neighbors, and if each ball grows at a constant rate to fill the gap, each ball grows into a dodecahedron. According to the face centered cubic arrangement diagram, there are 4 atoms, 4 octahedral gaps (duty ratio 1/3) and 8 tetrahedral gaps (duty ratio 2/3) in each unit cell.
According to the first rule of pallin, the number of anions surrounding a cation in a crystal structure is determined by the ratio of the diameters of the two ions. In the ZTA ceramic green body, the alumina and zirconia grains are assumed to be spherical and arranged in a cubic packing, and in one basic unit, the alumina grains have 4 numbers and a diameter Da(ii) a 4 zirconia particles are filled into the octahedral gap with the diameter Dz eightAnother 8 zirconia grains with a diameter D filled into the tetrahedral gapz four. After sintering is complete, the volume fraction V of the zirconia particles is assumedzWithout change, the volume fraction of zirconia grains in the ZTA ceramic is formula (3):
after simplification of formula (3), formula (4) is obtained:
there are two types of gaps in the face centered cubic arrangement, octahedral gaps surrounded by 6 spheres and tetrahedral gaps surrounded by 4 spheres, only if the diameter D of the alumina grains isaAbove a certain threshold value, zirconia grains of a given size are unlikely to contact surrounding grains. According to the Pythagorean theorem, in the critical state, D is calculatedz eight/Da0.414. Similarly, D is calculated by the tetrahedral gap surrounded by 4 round ballsz four/Da0.225. The two diameters are substituted into formula (4) to obtain the volume fraction V of the zirconiaz＝8.57％。
In addition, Dz four/Da0.225, i.e. Da/DzWhen 4.444 is taken in formula (2), V is obtainedz3.30%. Will Dz eight/Da0.414, i.e. Da/DzWhen the expression (2) is expressed in 2.415, V is obtainedz17.56%. On the basis of the volume fraction, the optimal volume fraction range value of the zirconia is further determined through experiments.
The following examples 1 to 3 describe specific components and preparation methods of the ZTA ceramic material of the present invention, and the ceramic substrates obtained in the examples were tested, and the microstructure and structure of the sample were observed using an SU8220 field emission scanning electron microscope; measuring the volume density of the sintered sample by adopting an Archimedes drainage method; measuring the bending strength of the sample by adopting a three-point bending method; measuring the volume resistivity of the sample by using the method of GB/T5594.5-85; measuring the breakdown voltage resistance strength of the ceramic substrate by adopting an RK2671AM type voltage resistance tester; the dielectric constant of the sample is measured by the method described in GB/T5594.4-2015; the time temperature curve was measured using an H-RB18J-GF infrared thermometer.
Example 1
The components adopted in this example were: 96% of aluminum oxide and 4% of zirconium oxide according to the volume fraction of the powder; the total mass of the powder is 100 percent, and the solvent (ethanol 27: trichloroethylene 73) is 30 percent; 0.7 percent of castor oil phosphate serving as a dispersant; plasticizer octyl phthalate 4.5%; and 9% of adhesive polyvinyl butyral.
The preparation steps are as follows:
firstly, adding alumina, zirconia, a dispersant and a part of solvent into a ball mill according to a proportion, carrying out ball milling for 48 hours, and fully dispersing powder;
secondly, adding the plasticizer, the binder and the residual solvent into the ball mill, and continuing ball milling for 24 hours to fully and uniformly mix the components;
taking the slurry out of the ball mill into a defoaming machine, defoaming for 30min under the condition that the initial viscosity is 1000mPa & s and the negative pressure is lower than-0.085 MPa, and defoaming in vacuum to obtain casting slurry with the viscosity of 23000mPa & s;
fourthly, after the defoaming is finished, keeping the slurry in a defoaming machine at negative pressure and homogenizing for 1 hour at the rotating speed of 5 revolutions per minute;
fifthly, after homogenization, tape casting is carried out on a casting machine;
sixthly, drying and collecting materials, and ageing and homogenizing for more than 8 hours;
seventhly, punching;
and step eight, sintering and forming, wherein the sintering temperature is 1600-1630 ℃, and the temperature is kept for 4 hours.
By selecting proper powder grain size, after tape casting and sintering, the average grain size of alumina grains is about 1.5 μm, the average grain size of zirconia grains is about 0.6 μm, and the ratio D of the median grain size of alumina to that of zirconia is ensureda/DzAbout 2.5.
The density of the sintered material was found to be 3.98g/cm3The bending strength of the material is 550MPa to 580MPa, and the volume resistivity at normal temperature is 36 × 1014Omega cm to 38 × 1014Ω·cm。
The ceramic material composition is printed with platinum paste after the sixth step, and is subjected to laminating and isostatic pressing treatment, and then the seventh step and the eighth step to prepare the heating element, wherein the heating resistance is 1.5 +/-0.05 omega, and no material breakdown problem exists when the heating resistance is tested under the condition of heating voltage of 8V, but when the temperature is increased to above 700 ℃, the problem of heating chip explosion exists, which indicates that the strength of the material is low, the material fails under a certain thermal expansion condition, and the formula material can be used below the limit temperature of 600 ℃.
Example 2
The components adopted in this example were: according to the volume fraction of the powder, 91.43 percent of alumina and 8.57 percent of zirconia; taking the total mass of the powder as 100 percent and 28 percent of solvent (ethanol 27: trichloroethylene 73); 0.6 percent of castor oil phosphate serving as a dispersant; 4.1% of plasticizer dibutyl phthalate; adhesive polyvinyl butyral 8.6%. In this example, the average particle diameter of the zirconia powder was 0.25 μm; two kinds of alumina powder are added, one has an average particle size of 0.7 μm, and the other has an average particle size of 2.0 μm.
The preparation method comprises the following steps:
firstly, adding alumina, zirconia, a dispersant and a part of solvent into a ball mill according to a proportion, carrying out ball milling for 48 hours, and fully dispersing powder;
secondly, adding the plasticizer, the binder and the residual solvent into the ball mill, and continuing ball milling for 24 hours to fully and uniformly mix the components;
taking the slurry out of the ball mill into a defoaming machine, defoaming for 30min under the condition that the initial viscosity is 960mPa & s and the negative pressure is lower than-0.085 MPa, and defoaming in vacuum to obtain casting slurry with the viscosity of 22500mPa & s;
fourthly, after the defoaming is finished, keeping the slurry in a defoaming machine at negative pressure and homogenizing for 1 hour at the rotating speed of 5 revolutions per minute;
fifthly, after homogenization, tape casting is carried out on a casting machine;
sixthly, drying and collecting materials, and ageing and homogenizing for more than 8 hours;
seventhly, punching;
and step eight, sintering and forming the obtained casting green body, wherein the sintering temperature is 1600-1630 ℃, and the temperature is kept for 4 hours.
FIG. 1(a) shows a cast green body, the back-scattered image of a ZTA ceramic substrate grown as a ceramic crystal by sintering of the cast green body shown in FIG. 1(b) reveals zirconia grains having a grain size of 0.65 μm; the alumina grains also had two sizes, one having an average particle size of 1.55 μm and the other having an average particle size of 2.85. mu.m.
The density of the sintered material was measured to be 4.08g/cm3The bending strength of the material is 750MPa to 790MPa, and the volume resistivity at normal temperature is 23 × 1014Omega cm to 30 × 1014Ω·cm。
After the heating element is manufactured by adopting the same method as the embodiment 1, the heating resistance is 1.5 +/-0.05 omega, the problem of material breakdown is avoided when the heating element is tested under the condition of heating voltage of 8V, and the heating piece frying piece can still normally work when the temperature is increased to be close to 800 ℃, which shows that the strength of the material can completely meet the requirement when the material is used at the limit temperature of 800 ℃.
Example 3
The components adopted in this example were: according to the volume fraction of the powder, 88 percent of alumina and 12 percent of zirconia; based on the total mass of the powder as 100 percent, 26 percent of solvent (ethanol 27: trichloroethylene 73); 0.5 percent of castor oil phosphate serving as a dispersant; plasticizer octyl phthalate 4.0%; 8 percent of adhesive polyvinyl butyral.
The preparation steps are as follows:
firstly, adding alumina, zirconia, a dispersant and a part of solvent into a ball mill according to a proportion, carrying out ball milling for 48 hours, and fully dispersing powder;
secondly, adding the plasticizer, the binder and the residual solvent into the ball mill, and continuing ball milling for 24 hours to fully and uniformly mix the components;
taking the slurry out of the ball mill into a defoaming machine, defoaming for 30min under the condition that the initial viscosity is 950mPa & s and the negative pressure is lower than-0.085 MPa, and defoaming in vacuum to obtain casting slurry with the viscosity of 21000mPa & s;
fourthly, after the defoaming is finished, keeping the slurry in a defoaming machine at negative pressure and homogenizing for 1 hour at the rotating speed of 5 revolutions per minute;
fifthly, after homogenization, tape casting is carried out on a casting machine;
sixthly, drying and collecting materials, and ageing and homogenizing for more than 8 hours;
seventhly, punching;
and step eight, sintering and forming, wherein the sintering temperature is 1600-1630 ℃, and the temperature is kept for 4 hours.
By selecting proper powder grain size, after tape casting and sintering, the average grain size of alumina grains is about 1.5 μm, the average grain size of zirconia grains is about 0.6 μm, and the ratio D of the median grain size of alumina to that of zirconia is ensureda/DzAbout 2.5.
The sintered material measured a density of 4.15g/cm3The bending strength of the material is 800MPa to 840MPa, and the volume resistivity at normal temperature is 12 × 1014Ω·cm。
After the heating element is manufactured by adopting the same method as the embodiment 1, the heating resistance is 1.5 +/-0.05 omega, the problem of material chipping does not exist when the heating element is tested under the condition of heating voltage of 8V, but the problem of heating chip breakdown exists when the temperature is increased to above 700 ℃, which shows that the resistivity of the material is seriously reduced at high temperature, and the material is unreliable when the heating element is used at above 700 ℃. Therefore, the formula material can be safely used at the limit temperature of 600 ℃.
Comparative example
The components used in this comparative example were: according to the volume fraction of the powder, the alumina accounts for 83.9 percent, and the zirconia accounts for 16.1 percent; taking the total mass of the powder as 100 percent, and 25 percent of solvent (ethanol 27: trichloroethylene 73); 0.5 percent of castor oil phosphate serving as a dispersant; 4.0% of plasticizer dibutyl phthalate; 8 percent of adhesive polyvinyl butyral.
The preparation steps are as follows:
firstly, adding alumina, zirconia, a dispersant and a part of solvent into a ball mill according to a proportion, carrying out ball milling for 48 hours, and fully dispersing powder;
secondly, adding the plasticizer, the binder and the residual solvent into the ball mill, and continuing ball milling for 24 hours to fully and uniformly mix the components;
taking the slurry out of the ball mill into a defoaming machine, defoaming for 30min under the condition that the negative pressure is lower than-0.085 MPa, and defoaming in vacuum to obtain casting slurry with the viscosity of 20000mPa & s;
fourthly, after the defoaming is finished, keeping the slurry in a defoaming machine at negative pressure and homogenizing for 1 hour at the rotating speed of 5 revolutions per minute;
fifthly, after homogenization, tape casting is carried out on a casting machine;
sixthly, drying and collecting materials, and ageing and homogenizing for more than 8 hours;
seventhly, punching;
eighthly, sintering and forming, wherein the sintering temperature is 1600-1630 ℃, and the temperature is kept for 4 h;
the density of the material after sintering was found to be 4.23g/cm3Bending strength of 820MPa to 850MPa, and room-temperature volume resistivity of 4.8 × 1014Ω·cm。
After the heating element is manufactured by adopting the same method as the embodiment 1, the heating resistance is 1.5 +/-0.05 omega, the problem of material chipping does not exist when the heating element is tested under the condition of heating voltage of 8V, but the problem of heating chip breakdown exists when the temperature is increased to be more than 300 ℃, the resistivity of the material is seriously reduced at high temperature, and the heating element is unreliable when the heating element is used at the temperature of more than 300 ℃.
Specifically, the ZTA ceramic substrates obtained in example 2 and comparative example were used to prepare test bars, and the results of the performance test are shown in table 1 below.
TABLE 1ZTA ceramic substrate Properties
The bending strength of the ZTA ceramic material prepared when the volume fraction of the zirconium oxide is 16.1 percent almost reaches the maximum value of the ZTA ceramic sintered under normal pressure, and the volume resistance at normal temperature also meets the requirement of a ceramic substrate, but the volume resistivity is sharply reduced to be lower than the standard value at high temperature and does not meet the requirement of the ceramic substrate, after 10KV alternating current is applied to two sides of the substrate, the substrate is broken down, the ultra-leakage phenomenon occurs, the ZTA ceramic substrate prepared when the volume fraction of the zirconium oxide is 8.57 percent has the volume resistivity of 6.9 × 10 at the high temperature of 600 DEG C10Omega cm, far higher than the high-temperature volume resistivity requirement of the ceramic substrate. Under the critical volume state, the zirconia crystal grains are just surrounded by the alumina crystal grains, so that a continuous conductive phase is not formed, and the mechanical property of the ZTA ceramic is ensured.
To further compare the current carrying properties of the heating elements made of the ZTA ceramic materials of example 2 and comparative example, platinum resistance pastes were printed on ZTA cast green bodies of 8.57% zirconia and 16.1% zirconia, respectively, and then a sheet of the same size was covered to laminate, isostatic pressed with 95 ℃ warm water, and then co-fired at 1600 ℃ to form a high temperature co-fired ceramic heating element having a length and width of 19 × 4.7 × 0.38mm, a heating element length of 10.5mm, and an average resistance value of 1.25 Ω, and the following tests were performed:
the voltage of 8V is respectively applied to the two ceramic elements, the power for starting the electricity is 51.2W, and the power born by the cold start of the heating sheet is 1508W/cm3The power borne by the common alumina ceramic heating plate during starting is generally not more than 500W/cm3. The bending strength of the ZTA ceramic heating sheet is one time of that of a common alumina ceramic heating sheet, and the unit volume power which can be born by cold start is three times of that of the common alumina ceramic heating sheet. The results of the energization test are shown in FIG. 2 after the two ZTA heating sheets are energized for 60 seconds.
Applying 8V voltage to two ends of the ZTA ceramic heating sheet electrode with 16.1% zirconia content, and electrifying for 0.5 s to obtain a current of 3.3A; after the power is supplied for 15 seconds, the current is reduced and stabilized at about 0.75A, the surface temperature of the heating sheet is close to 800 ℃, and as shown in figure 2(a), the heating wires in the middle of the heating sheet are connected together by bright lines. After the heating plate is cooled, as shown in fig. 2(b), black spots appear between the heating wires corresponding to the bright lines, which indicates that leakage current occurs between the heating plate printed resistance lines, and the insulation performance of the ZTA ceramic with 16.1% zirconia content cannot meet the requirements of the ceramic substrate.
The ZTA ceramic heating sheet with zirconia content of 8.57% is placed into a heating furnace, the resistance of the heating sheet is increased along with the temperature rise in the furnace, and the resistance temperature curve is measured as shown in figure 3. As can be seen from FIG. 3, this platinum and ZTA co-fired ceramic is a linear positive temperature coefficient heating element.
When the ZTA ceramic heating plate of 8.57% zirconia is electrified for 3 seconds, the temperature of the heating plate rises to 536 ℃, which shows that the ZTA ceramic heating plate has high power and high temperature rise speed, and the change curve of the temperature along with time is shown in figure 4. After electrifying for 15 seconds, the surface temperature of the heating sheet is stabilized at about 792 ℃, and gaps among the red heating wires are clearly visible, as shown in figure 2 (c). After cooling, as shown in fig. 2(d), no black spots appeared between the heater elements of the heater sheet, indicating that the high-temperature volume resistivity of the ZTA ceramic heater sheet of 8.57% zirconia satisfies the requirement of the insulating property of the ceramic substrate.
Finally, it should be emphasized that the above-described embodiments are merely preferred examples of the invention, which is not intended to limit the invention. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (10)
1. The ZTA ceramic material is characterized by being prepared by sintering a composition containing powder, wherein the powder consists of the following components in percentage by volume:
88 to 96 percent of alumina powder;
4 to 12 percent of zirconia powder;
the grain size ratio of the alumina to the zirconia after sintering is 2.380 to 4.444.
2. A ZTA ceramic material according to claim 1, wherein:
the volume fraction of the alumina powder is 91-92%, and the volume fraction of the zirconia powder is 8-9%;
the alumina powder or the zirconia powder is mixed powder formed by mixing two kinds of powder with different average grain diameters; in the mixed powder, a first partial volume ratio of a grain size ratio of alumina to zirconia after sintering of 2.380 to 2.415 is 1/3, and a second partial volume ratio of a grain size ratio of alumina to zirconia after sintering of 4.380 to 4.444 is 2/3.
3. A ZTA ceramic material according to claim 1 or 2, wherein:
the volume fraction of the alumina powder is 91.43%, and the volume fraction of the zirconia powder is 8.57%;
the composition also comprises a solvent, a dispersant, a plasticizer and a binder, wherein the ZTA ceramic material is formed by casting and sintering the composition;
the mass of the dispersing agent is 0.5 to 0.7%, the mass of the plasticizer is 4.0 to 4.5%, and the mass of the adhesive is 8.0 to 9.0%, relative to 100% of the mass of the powder, 25 to 30% of the mass of the solvent, and 0.5 to 0.7% of the mass of the dispersing agent;
the alumina is alpha-alumina;
the zirconia is 3Y zirconia;
the solvent is absolute ethyl alcohol and trichloroethylene according to the mass ratio of 27: 73, or the solvent is a binary azeotropic mixture of absolute ethyl alcohol and butanone;
the dispersing agent is phosphate ester;
the plasticizer is phthalate;
the adhesive is polyvinyl butyral.
4. A ZTA ceramic heating element comprising a ZTA ceramic material according to any one of claims 1 to 3 and a heating resistor, said ZTA ceramic heating element being formed by co-firing said heating resistor at a high temperature after printing said heating resistor on said composition before sintering said composition.
5. A ZTA ceramic heating element according to claim 4, wherein:
the heating resistor is tungsten, and the high-temperature co-firing is carried out in a reducing atmosphere at 1500-1650 ℃; or the heating resistor is platinum, and the high-temperature co-firing is carried out at 1500-1650 ℃ in an oxidizing atmosphere.
6. A preparation method of ZTA ceramic material is characterized in that:
preparing powder according to the following volume fractions: 88 to 96 percent of alumina powder and 4 to 12 percent of zirconia powder; preparing the following auxiliary components in percentage by mass based on 100% of the mass of the powder: 25 to 30 percent of solvent, 0.5 to 0.7 percent of dispersant, 4.0 to 4.5 percent of plasticizer and 8.0 to 9.0 percent of adhesive; and performing the following steps:
the method comprises the following steps: grinding and dispersing alumina, zirconia, a dispersant and a part of solvent;
step two: adding the plasticizer, the binder and the residual solvent, and continuously grinding and dispersing;
step three: defoaming;
step four: homogenizing;
step five: tape casting;
step six: drying, collecting, aging and homogenizing;
step seven: sintering and forming, wherein the grain size ratio of the sintered alumina to the sintered zirconia is 2.380 to 4.444.
7. The method of claim 6, wherein the ceramic material is a ZTA ceramic material, comprising the following steps:
the first step and the second step are carried out in a ball mill, and the grinding time of the first step and the second step is respectively 24-48 h;
defoaming in a defoaming machine under the condition that the negative pressure is lower than-0.085 MPa for 25-40 min to obtain casting slurry with the viscosity of 20000-24000 mPa & s;
step four, the process is carried out in a defoaming machine, the negative pressure is kept, and the homogenization is carried out for 0.5 to 2 hours at the rotating speed of 3 to 6 r/min;
step five, casting and molding on a casting machine;
ageing and homogenizing for more than 8 hours in the sixth step;
and step seven, pressureless sintering is carried out for 3 to 6 hours in a high-temperature kiln at 1500 to 1650 ℃.
8. The method of preparing a ZTA ceramic material according to claim 6 or 7, wherein:
the punching step is also included between the sixth step and the seventh step: punching the green body obtained in the sixth step to a required size;
the sintering temperature of the seventh step is 1600-1630 ℃.
9. The method of preparing a ZTA ceramic material according to claim 6 or 7, wherein:
the method also comprises the following steps between the sixth step and the seventh step: printing a heating resistor on the green body obtained in the step six, covering a sheet of the green body for lamination, and then carrying out isostatic pressing treatment; co-firing at high temperature in the seventh step to obtain a ZTA ceramic heating element;
the heating resistor is tungsten, and the high-temperature co-firing is carried out in a reducing atmosphere; or the heating resistor is platinum, and the high-temperature co-firing is carried out in an oxidizing atmosphere.
10. The method of preparing a ZTA ceramic material according to claim 6 or 7, wherein:
the volume fraction of the alumina powder is 91.43%, and the volume fraction of the zirconia powder is 8.57%; one of the alumina powder or the zirconia powder is mixed powder formed by mixing two kinds of powder with different average grain diameters; in the mixed powder, a first partial volume ratio of a grain size ratio of alumina to zirconia after sintering of 1/3 is 2.380 to 2.415, and a second partial volume ratio of a grain size ratio of alumina to zirconia after sintering of 4.380 to 4.444 is 2/3;
the alumina is alpha-alumina;
the zirconia is 3Y zirconia;
the solvent is absolute ethyl alcohol and trichloroethylene according to the mass ratio of 27: 73, or the solvent is a binary azeotropic mixture of absolute ethyl alcohol and butanone;
the dispersing agent is phosphate ester;
the plasticizer is phthalate;
the adhesive is polyvinyl butyral.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010508689.4A CN111646782A (en) | 2020-06-06 | 2020-06-06 | ZTA ceramic material, heating element and preparation method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010508689.4A CN111646782A (en) | 2020-06-06 | 2020-06-06 | ZTA ceramic material, heating element and preparation method thereof |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN111646782A true CN111646782A (en) | 2020-09-11 |
Family
ID=72341104
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010508689.4A Pending CN111646782A (en) | 2020-06-06 | 2020-06-06 | ZTA ceramic material, heating element and preparation method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111646782A (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112430072A (en) * | 2020-11-24 | 2021-03-02 | 广东国研新材料有限公司 | Co-fired laminated porous ceramic heating body and preparation method thereof |
| CN113105216A (en) * | 2021-04-07 | 2021-07-13 | 盐城工学院 | A kind of injection-molded zirconium-aluminum composite ceramic and preparation method thereof |
| CN114685147A (en) * | 2020-12-28 | 2022-07-01 | 财团法人工业技术研究院 | Ceramic materials and wire nozzles |
| CN116490480A (en) * | 2020-10-15 | 2023-07-25 | 贺利氏科纳米北美有限责任公司 | Zirconia toughened alumina ceramic sintered body |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105881700A (en) * | 2016-05-26 | 2016-08-24 | 郑州中瓷科技有限公司 | High-strength ceramic substrate and preparation method and production line thereof |
| CN109293345A (en) * | 2018-11-23 | 2019-02-01 | 郑州中瓷科技有限公司 | High reflectance high-strength ceramic substrate and preparation method thereof |
| CN110167221A (en) * | 2019-04-29 | 2019-08-23 | 中研香诚(北京)科技有限公司 | A kind of ceramic heating flake and preparation method thereof |
-
2020
- 2020-06-06 CN CN202010508689.4A patent/CN111646782A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105881700A (en) * | 2016-05-26 | 2016-08-24 | 郑州中瓷科技有限公司 | High-strength ceramic substrate and preparation method and production line thereof |
| CN109293345A (en) * | 2018-11-23 | 2019-02-01 | 郑州中瓷科技有限公司 | High reflectance high-strength ceramic substrate and preparation method thereof |
| CN110167221A (en) * | 2019-04-29 | 2019-08-23 | 中研香诚(北京)科技有限公司 | A kind of ceramic heating flake and preparation method thereof |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116490480A (en) * | 2020-10-15 | 2023-07-25 | 贺利氏科纳米北美有限责任公司 | Zirconia toughened alumina ceramic sintered body |
| CN112430072A (en) * | 2020-11-24 | 2021-03-02 | 广东国研新材料有限公司 | Co-fired laminated porous ceramic heating body and preparation method thereof |
| CN114685147A (en) * | 2020-12-28 | 2022-07-01 | 财团法人工业技术研究院 | Ceramic materials and wire nozzles |
| US11964915B2 (en) | 2020-12-28 | 2024-04-23 | Industrial Technology Research Institute | Ceramic material and wire bonding capillary |
| CN113105216A (en) * | 2021-04-07 | 2021-07-13 | 盐城工学院 | A kind of injection-molded zirconium-aluminum composite ceramic and preparation method thereof |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN111646782A (en) | ZTA ceramic material, heating element and preparation method thereof | |
| CN101321415B (en) | Rare earth thick film circuit electrical heating element based on aluminum nitride minicrystal ceramic substrates and its preparation technique | |
| US11866370B2 (en) | Grain-grade zirconia toughened alumina ceramic substrate and method for preparing the same | |
| CN102685942B (en) | Intelligent electric-heating element with PTC (Positive Temperature Coefficient) rare-earth thick film circuit and preparation method thereof | |
| CN105859263B (en) | A kind of 96 aluminium oxide ceramics of high-performance and preparation method thereof | |
| EP2767524A1 (en) | Silicon nitride substrate and method for manufacturing silicon nitride substrate | |
| CN102249666B (en) | A kind of preparation method of direct current zinc oxide resistor sheet | |
| KR20100134767A (en) | Lead-Free Resistance Compositions with Ruthenium Oxide | |
| CN105810291A (en) | Rare-earth resistance paste of medium- and low-resistance high-power thick film circuit and preparation method of rare-earth resistance paste | |
| JP2013157195A (en) | Inorganic all-solid secondary battery | |
| JP6966717B2 (en) | Thick film resistor composition and thick film resistance paste containing it | |
| CN109734480A (en) | A kind of aluminium nitride ceramics heater cofiring high temperature exothermic slurry and preparation method thereof | |
| CN106571172A (en) | Aluminum alloy substrate thick film circuit intermediate-temperature sintering dielectric paste and preparation method thereof | |
| CN116283251B (en) | Alumina ceramic and preparation method and application thereof | |
| CN116425528B (en) | Dielectric ceramic material and chip type multilayer ceramic capacitor prepared from same | |
| CN106747420A (en) | A kind of X5R types multilayer ceramic capacitor thin-medium material and preparation method thereof | |
| KR101138246B1 (en) | Manufacturing method of paste composition having low temperature coefficient resistance for resistor, thick film resistor and manufacturing method of the resistor | |
| CN100415689C (en) | Method for producing ceramic slurry, green sheet and laminated ceramic parts | |
| CN1654420A (en) | Dielectric ceramic material for chip capacitor and preparation method thereof | |
| KR101138238B1 (en) | Manufacturing method of paste composition for resistor using coating metal oxide, thick film resistor and manufacturing method of the resistor | |
| CN109384392B (en) | Glass composition and glass powder | |
| KR100648001B1 (en) | Ceramic heater | |
| CN113170926A (en) | Integrally conductive aerosol generation substrate heating body and preparation process and application thereof | |
| KR101166709B1 (en) | Manufacturing method of paste composite for resistor, thick film resistor and manufacturing method of the resistor | |
| KR102727291B1 (en) | Method for controlling thermal conductivity and bending strength of silicon nitride substrate |
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 | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20200911 |