CN108675789A - A kind of new iron-based ceramic capacitor material and preparation method thereof - Google Patents

A kind of new iron-based ceramic capacitor material and preparation method thereof Download PDF

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Publication number
CN108675789A
CN108675789A CN201810706016.2A CN201810706016A CN108675789A CN 108675789 A CN108675789 A CN 108675789A CN 201810706016 A CN201810706016 A CN 201810706016A CN 108675789 A CN108675789 A CN 108675789A
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ceramic capacitor
capacitor material
baco
powder
hours
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胡长征
郭哲
吴山
方亮
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Guilin University of Technology
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Guilin University of Technology
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    • 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
    • C04B35/495—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 vanadium, niobium, tantalum, molybdenum or tungsten oxides or solid solutions thereof with other oxides, e.g. vanadates, niobates, tantalates, molybdates or tungstates
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    • C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/50—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on rare-earth compounds
    • C—CHEMISTRY; METALLURGY
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    • 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
    • C04B2235/327—Iron group oxides, their mixed metal oxides, or oxide-forming salts thereof
    • C04B2235/3272—Iron oxides or oxide forming salts thereof, e.g. hematite, magnetite
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    • C04B2235/30—Constituents and secondary phases not being of a fibrous nature
    • C04B2235/44—Metal salt constituents or additives chosen for the nature of the anions, e.g. hydrides or acetylacetonate
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Abstract

The invention discloses a kind of iron-based ceramic capacitor materials and preparation method thereof.By BaCO3、Sm2O3、Fe2O3And Nb2O5Advance ball milling refines raw material, according to stoichiometric ratio Ba4‑xSm2Fe2‑xNb8+ xO30(x=0.025,0.05,0.075 and 0.1) carry out dispensing ceramic capacitor material Ba is prepared using solid phase reaction by processes such as pre-burning, secondary ball millings4‑xSm2Fe2‑xNb8+xO30.The method of the present invention can get excellent temperature stability dielectric ceramic material, its dielectric properties is also relatively stablized at a high temperature of room temperature is to 400 DEG C；The method of the present invention is simple, energy-saving and emission-reduction, and moderate cost is suitable for mass production.

Description

A kind of new iron-based ceramic capacitor material and preparation method thereof
Technical field
The present invention relates to a kind of new iron-based ceramic capacitor material Ba4-xSm2Fe2-xNb8+xO30(x=0.025,0.05, 0.1) and preparation method thereof 0.075 and, belong to the technical field of ceramic material of electronic component.
Background technology
Ceramic capacitor is the important foundation device of electronic information technology, with the rapid development of electronic device, it is desirable that pottery Porcelain condenser material being capable of more diversification.Most of ceramic capacitors are based on perovskite structure, and the present invention uses tungsten bronze structure, Contribute to the material type of expanded capacitor device ceramics.At present for the research of tungsten bronze and report or relatively small number of, therefore Research and application to tungsten bronze series compound will have very good application prospect.Tungsten bronze series compound also may be used As perovskite structure compound has unique and excellent performance in ferroelectricity, piezoelectricity, pyroelectricity, nonlinear optics etc., The technical fields such as laser freuqency doubling, Electro-optical Modulation, optical Information Processing, superconduction, humidity sensor, solid fuel cell are answered With.
Invention content
1. the object of the present invention is to provide a kind of new iron-based ceramic capacitor materials and preparation method thereof.
2. the chemical constitution formula that the present invention provides material is Ba4-xSm2Fe2-xNb8+xO30。
3. the preparation method of above-mentioned new iron-based ceramic capacitor material the specific steps are：
(1) purity is more than to 99.9% BaCO3, Sm2O3, Fe2O3And Nb2O5For starting material, respectively according to：
X=0.025 is BaCO3：Sm2O3：Fe2O3：Nb2O5=3.975:1：0.9875:4.0125
X=0.05 is BaCO3：Sm2O3：Fe2O3：Nb2O5=3.950:1：0.9750:4.0250
X=0.075 is BaCO3：Sm2O3：Fe2O3：Nb2O5=3.925:1：0.9625:4.0375
X=0.1 is BaCO3：Sm2O3：Fe2O3：Nb2O5=3.900:1：0.9500:4.0500 molar ratio carries out dispensing, It is added in absolute ethyl alcohol, mixing and ball milling 8 hours, dries the powder for being made uniformly mixed；
(2) being pre-sintered 4 hours at 1100 DEG C according to powder made from step (1), the powder after pre-burning is made；
(3) by the powder after step (2) pre-burning, ball milling is uniformly mixed for 4 hours in absolute ethyl alcohol, drying；7wt% is added Polyvinyl alcohol water solution is granulated, and is crossed compression moulding after 60 mesh sieve, is subsequently placed in high temperature furnace air atmosphere, is burnt at 1250 DEG C Cooled to room temperature after knot 6 hours obtains the iron-based ceramic capacitor material Ba4-xSm2Fe2-xNb8+xO30。
A concentration of 7wt% of the polyvinyl alcohol water solution.
4. new ceramics capacitor material provided by the invention and preparation method thereof helps to expand using tungsten bronze structure Open up the material type of condenser ceramics.The present invention prepares ceramic material using traditional solid phase method, and being sintered under medium temperature can obtain The more excellent new ceramic material of performance is obtained, and simple process and low cost is honest and clean, environmental sound.In China, media ceramic material Material is among continuous development, so searching out new structural preparation method, the material type of expanded capacitor device ceramics is At present needed for the epoch.Thus, ceramic capacitor dielectric material provided by the present invention and preparation method thereof has good industry Change foreground.
Description of the drawings
1. Fig. 1 is Ba4-xSm2Fe2-xNb8+xO30The X-ray collection of illustrative plates of ceramics sample；
2. Fig. 2 is Ba4-xSm2Fe2-xNb8+xO30The surface microstructure photo of ceramic capacitor material；
3. Fig. 3 is Ba4-xSm2Fe2-xNb8+xO30The room temperature spectrogram of ceramic capacitor material；
4. Fig. 4 is Ba4-xSm2Fe2-xNb8+xO30The dielectric constant and loss variation with temperature of ceramic capacitor material.
Specific implementation mode
It is that raw material is respectively stoichiometrically by barium carbonate, samarium sesquioxide, di-iron trioxide and niobium pentaoxide Ba4-xSm2Fe2-xNb8+xO30Four parts of dispensings of (x=0.025,0.05,0.075 and 0.1) are put into ball grinder；Selective oxidation zirconium Ball and nylon tank；Added powder quality is the 8% of mill ball quality；Ball-milling Time is 10 hours, and rotating speed is 350 revs/min, ball Grinding media is absolute ethyl alcohol.Products therefrom is placed in 100 DEG C of baking oven and dries 5 hours, is first risen to 5 DEG C/minute of heating rate 1100 DEG C of pre-burnings 4 hours；It takes out the powder after pre-burning to grind, ball milling 4 hours, are ground into powdery again after drying, with quality hundred Point a concentration of 7% polyethanol aqueous solution (PVA) is granulated as organic binder, after evenly mixing, after the sieve of 60 mesh of mistake 100MPa pressure depresses to a diameter of 10mm, and thickness is the disc-shaped green compact of 1mm, by disc-shaped green compact with 1.5 DEG C/minute of heating Rate rises to 550 DEG C, keeps the temperature 4 hours discharge colloids and rises to 1260 DEG C again with 5 DEG C/minute of heating rate, 6 hours is kept the temperature, with stove Cooled to room temperature.Obtain iron-based ceramic material Ba4-xSm2Fe2-xNb8+xO30。
Fig. 1 is the X-ray diffraction spectrogram of sample, and Fig. 2 is the surface microscopic topographic of sample, X-ray diffraction spectrogram and table Face microscopic appearance shows Ba4-xSm2Fe2-xNb8+xO30Ceramics are tungsten bronze structure.
Silver electrode is burnt into ceramic capacitor material both sides made from the present embodiment, wafer capacitance device is made, then surveys Try and calculate the dielectric properties of the ceramic capacitor material.Attached drawing 3 gives the dielectric constant of the dielectric ceramic capacitor material With loss relationship with frequency change.Attached drawing 4 gives Ba4-xSm2Fe2-xNb8+xO30The dielectric constant of ceramic capacitor material and Variation with temperature is lost, shows Ba4-xSm2Fe2-xNb8+xO30Ceramic material phase within the temperature range of 0 DEG C -400 DEG C in high frequency 150-250 is maintained to dielectric constant, further proves that it can be used as ceramic capacitor material.

Claims (2)

1. a kind of new iron-based ceramic capacitor material, it is characterised in that the ceramic capacitor material is unfilled type tungsten bronze Structure, chemical constitution formula Ba4-xSm2Fe2-xNb8+xO30(x=0.025,0.05,0.075 and 0.1)；
The preparation method of the ceramic capacitor material the specific steps are：
(1) purity is more than to 99.9% BaCO3, Sm2O3, Fe2O3And Nb2O5For starting material, respectively according to：
X=0.025 is BaCO3：Sm2O3：Fe2O3：Nb2O5=3.975:1：0.9875:4.0125
X=0.05 is BaCO3：Sm2O3：Fe2O3：Nb2O5=3.950:1：0.9750:4.0250
X=0.075 is BaCO3：Sm2O3：Fe2O3：Nb2O5=3.925:1：0.9625:4.0375
X=0.1 is BaCO3：Sm2O3：Fe2O3：Nb2O5=3.900:1：0.9500:4.0500
Molar ratio carry out dispensing, be added in absolute ethyl alcohol, mixing and ball milling 8 hours, dry the powder for being made uniformly mixed；
(2) being pre-sintered 4 hours at 1100 DEG C according to powder made from step (1), the powder after pre-burning is made；
(3) by the powder after step (2) pre-burning, ball milling is uniformly mixed for 4 hours in absolute ethyl alcohol, drying；The poly- second of 7wt% is added Enol aqueous solution is granulated, and is crossed compression moulding after 60 mesh sieve, is subsequently placed in high temperature furnace air atmosphere, 6 are sintered at 1250 DEG C Cooled to room temperature after hour, obtains the iron-based ceramic capacitor material Ba4-xSm2Fe2-xNb8+xO30。
2. ceramic capacitor material according to claim 1, it is characterised in that the structure of the ceramic capacitor material For tungsten bronze structure, and relative dielectric constant is maintained at the range of 150-250 within the temperature range of 0 DEG C -400 DEG C in high frequency It is interior.
CN201810706016.2A 2018-06-27 2018-06-27 A kind of new iron-based ceramic capacitor material and preparation method thereof Pending CN108675789A (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111087023A (en) * 2019-11-28 2020-05-01 郑州轻工业大学 Room temperature multiferroic material Ba4SmFe0.5Nb9.5O30Preparation method of (1) and prepared room-temperature multiferroic material

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104446468A (en) * 2014-11-30 2015-03-25 桂林理工大学 X9R ceramic capacitor dielectric material and preparation method thereof
CN107840659A (en) * 2017-12-04 2018-03-27 福州大学 A kind of tungsten bronze pure phase room temperature multiferroic ceramics and preparation method thereof
CN107986784A (en) * 2017-12-04 2018-05-04 福州大学 A kind of tungsten bronze pure phase room temperature multiferroic ceramic thick film and preparation method thereof
CN108101538A (en) * 2017-12-29 2018-06-01 陕西科技大学 A kind of tungsten bronze type high energy storage density ceramic material and preparation method thereof
CN108147815A (en) * 2017-12-29 2018-06-12 陕西科技大学 A kind of single-phase multiferroic ceramic material of tungsten bronze type and preparation method thereof

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104446468A (en) * 2014-11-30 2015-03-25 桂林理工大学 X9R ceramic capacitor dielectric material and preparation method thereof
CN107840659A (en) * 2017-12-04 2018-03-27 福州大学 A kind of tungsten bronze pure phase room temperature multiferroic ceramics and preparation method thereof
CN107986784A (en) * 2017-12-04 2018-05-04 福州大学 A kind of tungsten bronze pure phase room temperature multiferroic ceramic thick film and preparation method thereof
CN108101538A (en) * 2017-12-29 2018-06-01 陕西科技大学 A kind of tungsten bronze type high energy storage density ceramic material and preparation method thereof
CN108147815A (en) * 2017-12-29 2018-06-12 陕西科技大学 A kind of single-phase multiferroic ceramic material of tungsten bronze type and preparation method thereof

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Title
CHANGZHENG HU ET AL.: "Relaxor behavior and ferroelectric properties of a new Ba4SmFe0.5Nb9.5O30 tungsten bronze ceramic", 《CERAMICS INTERNATIONAL》 *
CHANGZHENG HU ET AL.: "Temperature-stable unfilled tungsten bronze dielectric ceramics: Ba3.5Sm1.5Fe0.75Nb9.25O30", 《INT J APPL CERAM TECHNOL》 *
LIANG FANG ET AL.: "Dielectric Properties of Ba4Sm2Fe2M8O30 (M=Nb, Ta) with Tetragonal Bronze Structure", 《J. AM. CERAM. SOC.》 *

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111087023A (en) * 2019-11-28 2020-05-01 郑州轻工业大学 Room temperature multiferroic material Ba4SmFe0.5Nb9.5O30Preparation method of (1) and prepared room-temperature multiferroic material
CN111087023B (en) * 2019-11-28 2022-05-20 郑州轻工业大学 Room temperature multiferroic material Ba4SmFe0.5Nb9.5O30Preparation method of (2) and prepared room-temperature multiferroic material

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Application publication date: 20181019