CN108314445B - Barium dititanate ceramic with wide Curie temperature zone and preparation method thereof - Google Patents
Barium dititanate ceramic with wide Curie temperature zone and preparation method thereof Download PDFInfo
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Abstract
The invention relates to barium dititanate with a wide Curie temperature zone and a preparation method thereof, wherein the barium dititanate is prepared by the following steps: 1) dissolving one of cerium acetylacetonate hydrate, samarium nitrate hexahydrate and europium nitrate hexahydrate and barium acetate in glacial acetic acid to obtain a barium source solution; 2) dissolving tetrabutyl titanate in ethylene glycol monomethyl ether to obtain a titanium source solution; 3) mixing the barium source solution and the titanium source solution, aging and drying the obtained sol in the air to obtain dry gel, and then presintering, ball milling and drying to obtain barium dititanate powder; 4) and sequentially granulating, dry-pressing and forming, binder removal and pressureless sintering the barium dititanate powder to obtain the barium dititanate ceramic. The barium dititanate provided by the invention has a wider Curie temperature region, meets the design and use requirements of high-temperature ferroelectric devices, and has the advantage of good single-phase property.
Description
Technical Field
The invention belongs to the technical field of ceramic materials, and particularly relates to barium dititanate ceramic with a wide Curie temperature zone and a preparation method thereof.
Background
The ferroelectric material has a plurality of excellent characteristics such as piezoelectricity, pyroelectric property, ferroelectricity, electro-optic property, acousto-optic property and the like, and is widely applied in modern industry, wherein a ferroelectric memory, a driver, a sensor, a pyroelectric detector and the like are often required to be used in a high-temperature environment, and when the working temperature is higher than the Curie temperature of the ferroelectric material, the dielectric constant of the common ferroelectric material is obviously reduced, the dielectric loss is sharply increased, and the common ferroelectric material cannot normally work.
Barium dititanate has the advantages of high Curie temperature (about 470 ℃) and no lead, but because the Curie temperature zone is narrow, the barium dititanate has good dielectric property only in the narrow temperature zone near the Curie point, in order to ensure that the barium dititanate ceramic device can normally work in a wider high temperature range, the Curie temperature zone of the barium dititanate ceramic needs to be widened to ensure that the barium dititanate ceramic meets the requirements of high-temperature ferroelectric devicesAnd (5) use requirements. The current common method for preparing barium dititanate is BaCO3、TiO2The raw material is obtained by the traditional solid phase reaction method, and single valence doping elements are added to replace Ti on the basis of the traditional solid phase reaction method4+The Curie temperature zone is widened, but due to the fact that the thermodynamic stability zone of barium dititanate is narrow, the defects of low powder purity, high sintering temperature, poor phase stability and the like exist in the solid-phase preparation process, and the prepared ceramic often has the defects of low Curie peak value, unobvious Curie temperature zone widening effect and the like.
When the variable valence rare earth elements are adopted to dope and replace the A site or the B site of the barium dititanate, the difference of the ionic radius can cause lattice distortion, the change of the cell parameters can obviously affect the performance of the monoclinic structure barium dititanate belonging to the low symmetry center, and the composition fluctuation and the valence fluctuation brought by the introduction of the variable valence elements can cause different ferroelectric micro-regions and non-ferroelectric micro-regions in the barium dititanate ceramic. Compared with barium titanate, barium dititanate has a more complex crystal structure and three different TiO' s6Octahedron, the particularity of the structure causes that the property change is more sensitive to doping ions. Meanwhile, variable valence element doping is used, doping ions with different valence states exist in barium dititanate, and compared with single valence state ion doping, different substitution positions and valence state rising and falling caused by the radius difference of the ions with different valence states further strengthen the dispersion degree of the structure. These factors change the ferroelectric phase transition type of barium dititanate around the Curie temperature from normal ferroelectric phase transition to diffuse ferroelectric phase transition, and show the characteristic of dielectric peak broadening on the dielectric temperature spectrum. The powder is synthesized by a sol-gel method, the sintering temperature is reduced, the ceramic with fine crystal grains can be obtained by sintering, a large number of crystal boundaries can obstruct the rotation of electric domains to improve the dispersibility, variable-valence elements such as Ce, Sm, Eu and the like are used for doping on the basis, and the redox reaction of the variable-valence elements is controlled by adjusting the preparation process parameters such as the raw material proportion, the powder synthesis temperature, the sintering system, the atmosphere and the like, so that the Ce is doped3+And Ce4+、Sm2+And Sm3+、Eu2+With Eu3+The ions exist in the ceramics in proper proportion to further promote the phase change of barium dititanateThe phase transition of the dispersing property obviously widens the Curie temperature region, and meets the design and use requirements of the high-temperature ferroelectric device.
Disclosure of Invention
The invention aims to solve the technical problem of providing barium dititanate with a wide Curie temperature zone and a preparation method thereof aiming at the defects in the prior art.
In order to solve the technical problems, the technical scheme provided by the invention is as follows:
the barium dititanate ceramic with a wide Curie temperature zone is prepared by the following method:
1) dissolving one of cerium acetylacetonate hydrate, samarium nitrate hexahydrate and europium nitrate hexahydrate and barium acetate in glacial acetic acid to obtain a barium source solution;
2) dissolving tetrabutyl titanate in ethylene glycol monomethyl ether to obtain a titanium source solution;
3) mixing the barium source solution obtained in the step 1) with the titanium source solution obtained in the step 2) to ensure that the molar ratio of Ba: and Ti is 1:2, stirring for 10-14 h to obtain sol, aging and drying the sol in air to obtain dry gel, and presintering, ball-milling and drying to obtain barium dititanate powder;
4) and 3) sequentially granulating the barium dititanate powder obtained in the step 3), dry-pressing and forming, removing the glue, and sintering under no pressure to obtain the barium dititanate ceramic.
According to the scheme, the molar ratio of cerium, samarium or europium to barium in the barium source solution in the step 1) is 0.002-0.008: 1.
according to the scheme, the barium ion concentration in the barium source solution in the step 1) is 0.8-1.3 mol/L.
According to the scheme, the molar ratio of tetrabutyl titanate to ethylene glycol methyl ether in the step 2) is tetrabutyl titanate: ethylene glycol methyl ether ═ 1: 3.5 to 6.
According to the scheme, the aging time in the step 3) is 4-6 h.
According to the scheme, the drying process conditions in the step 3) are as follows: drying at 100-120 ℃ for 12-24 h.
According to the scheme, the pre-sintering process conditions in the step 3) are as follows: heating to 800-1000 ℃ at the speed of 4 ℃/min at room temperature, and preserving heat for 3-5 h.
According to the scheme, the ball milling process conditions in the step 3) are as follows: the rotating speed of the ball mill is 480-540 r/min, and the ball milling time is 10-12 h.
According to the scheme, PVA with the mass of 5% of barium dititanate powder is added in the granulation process in the step 4), and the mixture is sieved by a 100-mesh sieve after granulation.
According to the scheme, the pressure of the dry pressing in the step 4) is 150-200 MPa, and the pressure maintaining time is 1 min.
According to the scheme, the conditions of the glue discharging process in the step 4) are as follows: heating to 600-800 ℃ at the speed of 1 ℃/min at room temperature, and preserving heat for 2-4 h.
According to the scheme, the pressureless sintering process conditions in the step 4) are as follows: heating to 1150-1200 ℃ at room temperature at the rate of 4 ℃/min, and preserving heat for 3-6 h.
The invention also provides a preparation method of the barium dititanate ceramic with the wide Curie temperature zone, which comprises the following specific steps:
1) dissolving tetrabutyl titanate in ethylene glycol monomethyl ether to obtain a titanium source solution;
2) dissolving one of cerium acetylacetonate hydrate, samarium nitrate hexahydrate and europium nitrate hexahydrate and barium acetate in glacial acetic acid to obtain a barium source solution;
3) mixing the titanium source solution obtained in the step 1) with the barium source solution obtained in the step 2), stirring for 10-14 hours to obtain sol, aging and drying the obtained sol in air to obtain dry gel, and then presintering, ball-milling and drying to obtain barium dititanate powder;
4) and 3) sequentially granulating the barium dititanate powder obtained in the step 3), dry-pressing and forming, removing the glue, and sintering under no pressure to obtain the barium dititanate ceramic.
The barium dititanate is prepared by using glacial acetic acid as a solvent and a stabilizer and ethylene glycol methyl ether as a diluent, a barium dititanate precursor sol is prepared, and dried gel is obtained after aging and drying, and is sequentially ground, pre-sintered, ball-milled, granulated, dry-pressed and formed, subjected to gel discharge and sintered to obtain different ion-doped barium dititanate ceramics. Selecting variable-valence rare earth elements such as samarium, cerium, europium and the like as doping elements, and simultaneously using sol-gelBarium dititanate powder is synthesized by a glue method, and ceramics with fine crystal grains and high density are obtained by sintering. Doping element in place of Ba2+、Ti4+The change of the cell parameters has a significant influence on the performance of monoclinic barium dititanate belonging to a low symmetry center due to the distortion of the crystal lattice caused by ions, and the presence of titanium atoms in the barium dititanate in three states (specifically, 3 distorted TiO in the primitive cell structure of barium dititanate6Octahedron of Ti1O6、Ti2O6、Ti3O6For the three octahedrons, the chemical environments of Ti atoms are different), the doping of valence-variable elements is easy to cause component fluctuation and valence state fluctuation, so that different ferroelectric micro-regions and non-ferroelectric micro-regions are generated in the barium dititanate, and the barium dititanate is subjected to dispersive phase change, meanwhile, the ceramics obtained by synthesizing powder by a sol-gel method has a large number of crystal boundaries, and the ferroelectric domain movement is blocked to enhance the dispersibility, and the factors effectively widen the Curie temperature region of the barium dititanate.
The invention has the beneficial effects that: 1. the barium dititanate provided by the invention has a wider Curie temperature region, meets the design and use requirements of high-temperature ferroelectric devices, and has the advantage of good single-phase property. 2. The preparation method provided by the invention has the advantages of simple process, low requirement on equipment, lower powder synthesis and ceramic sintering temperature, easy control of doping amount and easy realization of mass production.
Drawings
FIG. 1 is an X-ray diffraction pattern of barium dititanate ceramics prepared in comparative example 1 and examples 1 to 3 of the present invention;
FIG. 2 is a graph showing the change of dielectric constant with temperature of barium dititanate ceramics prepared in comparative example 1 and examples 1 to 3.
Detailed Description
In order to make the technical solutions of the present invention better understood, the present invention is further described in detail below with reference to the accompanying drawings.
Comparative example 1
The barium dititanate ceramic is prepared by the following specific steps:
weighing 7.740g of barium acetate, dissolving the barium acetate in 25mL of glacial acetic acid to obtain a barium-containing solution, weighing 20.838g of tetrabutyl titanate, dissolving the tetrabutyl titanate in 20mL of ethylene glycol monomethyl ether to obtain a titanium-containing solution, mixing the barium-containing solution and the titanium-containing solution at normal temperature (the molar ratio of Ba to Ti is 1: 2), stirring for 12 hours to obtain a barium dititanate precursor sol, aging the obtained sol in air for 4 hours, drying in an electrothermal blowing drying oven at 120 ℃ for 24 hours to obtain a barium dititanate precursor dried gel, grinding the dried gel, presintering, heating to 850 ℃ at room temperature at the rate of 4 ℃/min, keeping the temperature for 3 hours to obtain barium dititanate powder, ball-milling the barium dititanate powder for 10 hours (the rotation speed of a ball mill is 540 rpm), drying the obtained slurry, adding 5 wt% of PVA (based on the weight) of the barium dititanate powder to carry out granulation, sieving by a 100-mesh sieve, and, keeping the pressure for 1min at 150MPa to prepare a small wafer blank, and carrying out glue removal on the blank, wherein the specific process conditions are as follows: heating to 600 ℃ at the speed of 1 ℃/min at room temperature, preserving heat for 2h, discharging glue, and sintering, wherein the specific process conditions are as follows: heating to 1170 ℃ at the speed of 4 ℃/min at room temperature, and preserving the heat for 3h to obtain the barium dititanate ceramic.
The composition of the ceramics obtained in this comparative example was analyzed by an X-ray diffractometer, model number Philips PANalytical X' Pert PW3050/60, the Netherlands. FIG. 1(a) is an XRD pattern of a ceramic prepared according to a comparative example of the present invention. From FIG. 1(a) to BaTi in FIG. 12O5As can be seen from the comparison of the standard cards, the ceramic prepared by the comparative example is pure phase barium dititanate, and no other impurity phase appears.
And (3) polishing the barium dititanate obtained in the comparative example, coating silver paste on two surfaces, and keeping the temperature at 800 ℃ for 20min to sinter the silver electrode. The silver-coated ceramic was subjected to dielectric temperature measurement using an Agilent HP1294A AC impedance analyzer. FIG. 2(a) is a thermogram of a ceramic prepared according to a comparative example of the present invention at 100kHz, from which it can be seen that the Curie temperature is 466 ℃ and the corresponding mesophilic peak is narrow.
Example 1
The barium dititanate with wide Curie temperature zone is prepared by the following steps:
7.740g of barium acetate and 0.040g of samarium nitrate hexahydrate are dissolved in 25mL of glacial acetic acid to obtain a barium source solution, 20.838g of tetrabutyl titanate is dissolved in 20mL of ethylene glycol monomethyl ether to obtain a titanium source solution, then the barium source solution and the titanium source solution are mixed at room temperature (the molar ratio of Ba to Ti to Sm is 1:2:0.003), the mixture is stirred for 12 hours to obtain barium dititanate precursor sol, the obtained sol is placed in air for aging for 4 hours, the obtained sol is placed in an electrothermal blowing drying oven at 120 ℃ for drying for 24 hours to obtain barium dititanate precursor xerogel, the xerogel is ground and presintered, the temperature is increased to 850 ℃ at the rate of 4 ℃/min at room temperature for heat preservation for 3 hours to obtain barium dititanate powder, the powder is ball-milled for 10 hours (the rotating speed of a ball mill is 540 r/min), then the ball-milled slurry is dried, 5 wt% of PVA of the barium dititanate powder is added for granulation, the granulation is screened, then, a dry pressing forming method is used, the pressure is maintained for 1min under 150MPa to prepare a small wafer blank, and the blank is subjected to glue removal, wherein the specific process conditions are as follows: heating to 600 ℃ at the speed of 1 ℃/min at room temperature, preserving heat for 2h, discharging glue, and sintering, wherein the specific process conditions are as follows: heating to 1170 ℃ at the speed of 4 ℃/min at room temperature, and preserving the heat for 3h to obtain the barium dititanate ceramic.
The composition of the ceramics obtained in this example was analyzed by an X-ray diffractometer, model number Philips PANalytical X' Pert PW3050/60, the Netherlands. FIG. 1(b) is an XRD pattern of a ceramic prepared according to an embodiment of the present invention. From FIG. 1(b) to BaTi in FIG. 12O5As can be seen from the comparison of the standard cards, the ceramic prepared in the embodiment is pure-phase barium dititanate, no other impurity phase occurs, and the samarium doping does not cause the decomposition of the barium dititanate.
The barium dititanate ceramic obtained in the embodiment is polished, silver paste is coated on two sides, and the barium dititanate ceramic is baked into a silver electrode by heat preservation at 800 ℃ for 20 min. The silver-coated ceramic was subjected to dielectric temperature measurement using an Agilent HP1294A AC impedance analyzer. FIG. 2(b) is a dielectric temperature spectrum of the ceramic prepared by the embodiment of the present invention at 100kHz, and it can be seen from the graph that the Curie temperature is 372 deg.C, and the corresponding dielectric temperature peak is significantly broadened compared with that in FIG. 2(a), and it can be known that the doping of samarium can broaden the Curie temperature region of barium dititanate ceramic.
Example 2
The barium dititanate with wide Curie temperature zone is prepared by the following steps:
7.740g of barium acetate and 0.054g of europium nitrate hexahydrate are dissolved in 25mL of glacial acetic acid to obtain a barium source solution, 20.838g of tetrabutyl titanate is dissolved in 20mL of ethylene glycol methyl ether to obtain a titanium source solution, then the barium source solution and the titanium source solution are mixed at room temperature (the molar ratio of Ba to Ti to Eu is 1:2:0.004), the mixture is stirred for 12 hours to obtain barium dititanate precursor sol, the obtained sol is placed in air for aging for 4 hours, then the sol is placed in a 120 ℃ electric heating blast drying oven for drying for 24 hours to obtain barium dititanate precursor xerogel, the xerogel is ground and presintered, the temperature is increased to 850 ℃ at the rate of 4 ℃/min at room temperature for 3 hours to obtain barium dititanate powder, the barium dititanate powder is ball-milled for 10 hours, then the ball-milled slurry is dried, 5 wt% of PVA of the barium dititanate powder is added for granulation, the granulation is carried out through a 100-mesh sieve after granulation, then a dry pressing molding method is used, a small wafer blank is, carrying out glue removal on the blank, wherein the specific process conditions are as follows: heating to 600 ℃ at the speed of 1 ℃/min at room temperature, preserving heat for 2h, discharging glue, and sintering, wherein the specific process conditions are as follows: heating to 1170 ℃ at the speed of 4 ℃/min at room temperature, and preserving the heat for 3h to obtain the barium dititanate ceramic.
The composition of the ceramics obtained in this example was analyzed by an X-ray diffractometer, model number Philips PANalytical X' Pert PW3050/60, the Netherlands. FIG. 1(c) is an XRD pattern of a ceramic prepared according to an embodiment of the present invention. From FIG. 1(c) to BaTi in FIG. 12O5As can be seen from the comparison of the standard cards, the ceramic prepared in this example is pure phase barium dititanate, no other impurity phase occurs, and the europium element doping does not cause the decomposition of barium dititanate.
The barium dititanate ceramic obtained in the embodiment is polished, silver paste is coated on two sides, and the barium dititanate ceramic is baked into a silver electrode by heat preservation at 800 ℃ for 20 min. The silver-coated ceramic was subjected to dielectric temperature measurement using an Agilent HP1294A AC impedance analyzer. FIG. 2(c) is a dielectric temperature spectrum of the ceramic prepared by the embodiment of the present invention at 100kHz, and it can be seen from the graph that the Curie temperature is 364 ℃, and the corresponding dielectric temperature peak is significantly broadened compared with that in FIG. 2(a), which indicates that the doping with europium can widen the Curie temperature region of the barium dititanate ceramic.
Example 3
The barium dititanate with wide Curie temperature zone is prepared by the following steps:
dissolving 7.740g of barium acetate and 0.052g of cerium (III) acetylacetonate hydrate in 25mL of glacial acetic acid to obtain a barium source solution, dissolving 20.838g of tetrabutyl titanate in 20mL of ethylene glycol monomethyl ether to obtain a titanium source solution, then mixing the barium source solution and the titanium source solution at room temperature (molar ratio Ba: Ti: Ce ═ 1:2:0.004), stirring for 12h to obtain barium dititanate precursor sol, placing the sol in air for aging for 4h, then placing in a 120 ℃ electric heating blast drying oven for drying for 24h to obtain barium dititanate precursor dry gel, grinding the dry gel, then presintering, heating to 900 ℃ at the room temperature at the rate of 4 ℃/min, keeping the temperature for 5h to obtain barium dititanate powder, carrying out ball milling for 10h on the powder, then drying the ball-milled slurry, adding 5 wt% of PVA of the barium dititanate powder for granulation, sieving by a 100-mesh sieve after granulation, and then using a dry-pressing molding method, keeping the pressure for 1min at 150MPa to prepare a small wafer blank, and carrying out glue removal on the blank, wherein the specific process conditions are as follows: heating to 600 ℃ at the speed of 1 ℃/min at room temperature, preserving heat for 2h, discharging glue, and sintering, wherein the specific process conditions are as follows: heating to 1190 ℃ at the speed of 4 ℃/min at room temperature, and preserving the temperature for 6h to obtain the barium dititanate ceramic.
The composition of the ceramics obtained in this example was analyzed by an X-ray diffractometer, model number Philips PANalytical X' Pert PW3050/60, the Netherlands. FIG. 1(d) is an XRD pattern of a ceramic prepared according to an embodiment of the present invention. From FIG. 1(d) to BaTi in FIG. 12O5As can be seen from comparison of the standard cards, the ceramic prepared in this example is pure-phase barium dititanate, no other impurity phase occurs, and the cerium doping does not cause decomposition of the barium dititanate.
The barium dititanate ceramic obtained in the embodiment is polished, silver paste is coated on two sides, and the barium dititanate ceramic is baked into a silver electrode by heat preservation at 800 ℃ for 20 min. The silver-coated ceramic was subjected to dielectric temperature measurement using an Agilent HP1294A AC impedance analyzer. FIG. 2(d) is a diagram of the dielectric temperature spectrum of the ceramic prepared by the embodiment of the present invention at 100kHz, and it can be seen from the diagram that the Curie temperature is 335 ℃, and the corresponding dielectric temperature peak is significantly broadened compared with that in FIG. 2(a), and it can be known that the doping of cerium can broaden the Curie temperature region of the barium dititanate ceramic.
Claims (9)
1. A barium dititanate ceramic with a wide Curie temperature zone is characterized by being prepared by the following method:
1) dissolving one of cerium acetylacetonate hydrate, samarium nitrate hexahydrate and europium nitrate hexahydrate and barium acetate in glacial acetic acid to obtain a barium source solution;
2) dissolving tetrabutyl titanate in ethylene glycol monomethyl ether to obtain a titanium source solution;
3) mixing the barium source solution obtained in the step 1) with the titanium source solution obtained in the step 2) to ensure that the molar ratio of Ba: ti = 1:2, stirring for 10-14 h to obtain sol, aging and drying the sol in air to obtain dry gel, and presintering, ball-milling and drying to obtain barium dititanate powder;
4) sequentially granulating, dry-pressing and forming, binder removal and pressureless sintering the barium dititanate powder obtained in the step 3) to obtain barium dititanate ceramic;
step 1), the molar ratio of cerium, samarium or europium to barium in the barium source solution is 0.002-0.008: 1;
step 4) the pressureless sintering process conditions are as follows: heating to 1150-1200 ℃ at room temperature at the rate of 4 ℃/min, and preserving heat for 3-6 h.
2. The barium dititanate ceramic with a wide Curie temperature zone according to claim 1, wherein the barium ion concentration in the barium source solution in step 1) is 0.8-1.3 mol/L.
3. The barium dititanate ceramic having a wide curie temperature zone of claim 1, wherein the molar ratio of tetrabutyl titanate to ethylene glycol methyl ether of step 2) is tetrabutyl titanate: ethylene glycol methyl ether = 1: 3.5 to 6.
4. The barium dititanate ceramic with a wide Curie temperature zone as claimed in claim 1, wherein the aging time in step 3) is 4-6 h, and the drying process conditions are as follows: drying at 100-120 ℃ for 12-24 h.
5. The barium dititanate ceramic with a wide curie temperature zone of claim 1, wherein the pre-sintering process conditions in step 3) are as follows: heating to 800-1000 ℃ at the speed of 4 ℃/min at room temperature, and preserving heat for 3-5 h.
6. The barium dititanate ceramic with the wide Curie temperature zone of claim 1, wherein PVA with the mass of 5% of barium dititanate powder is added in the granulation process of step 4), and the barium dititanate ceramic is sieved by a 100-mesh sieve after granulation.
7. The barium dititanate ceramic with a wide curie temperature range according to claim 1, wherein the pressure of the dry pressing in the step 4) is 150-200 MPa, and the dwell time is 1 min.
8. The barium dititanate ceramic with a wide curie temperature zone of claim 1, wherein the conditions of the step 4) are as follows: heating to 600-800 ℃ at the speed of 1 ℃/min at room temperature, and preserving heat for 2-4 h.
9. The method for preparing barium dititanate ceramic with wide Curie temperature zone according to any one of claims 1 to 8, wherein the method comprises the following steps:
1) dissolving tetrabutyl titanate in ethylene glycol monomethyl ether to obtain a titanium source solution;
2) dissolving one of cerium acetylacetonate hydrate, samarium nitrate hexahydrate and europium nitrate hexahydrate and barium acetate in glacial acetic acid to obtain a barium source solution;
3) mixing the titanium source solution obtained in the step 1) with the barium source solution obtained in the step 2), stirring for 10-14 hours to obtain sol, aging and drying the obtained sol in air to obtain dry gel, and then presintering, ball-milling and drying to obtain barium dititanate powder;
4) and 3) sequentially granulating the barium dititanate powder obtained in the step 3), dry-pressing and forming, removing the glue, and sintering under no pressure to obtain the barium dititanate ceramic.
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| CN102992756A (en) * | 2012-12-11 | 2013-03-27 | 武汉理工大学 | X8R-type capacitor ceramic material with high dielectric constant and preparation method thereof |
| CN106941045A (en) * | 2016-01-05 | 2017-07-11 | 三星电机株式会社 | Dielectric ceramic compositions, multilayer ceramic capacitor and its manufacture method |
| JP6641178B2 (en) * | 2015-12-28 | 2020-02-05 | サムソン エレクトロ−メカニックス カンパニーリミテッド． | Dielectric porcelain composition, method for producing the same, and ceramic electronic component |
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| CN102992756A (en) * | 2012-12-11 | 2013-03-27 | 武汉理工大学 | X8R-type capacitor ceramic material with high dielectric constant and preparation method thereof |
| JP6641178B2 (en) * | 2015-12-28 | 2020-02-05 | サムソン エレクトロ−メカニックス カンパニーリミテッド． | Dielectric porcelain composition, method for producing the same, and ceramic electronic component |
| CN106941045A (en) * | 2016-01-05 | 2017-07-11 | 三星电机株式会社 | Dielectric ceramic compositions, multilayer ceramic capacitor and its manufacture method |
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