CN103319177A - Microwave dielectric ceramic Ba3WTiO8 with low-temperature sintering characteristic and preparation method thereof - Google Patents
Microwave dielectric ceramic Ba3WTiO8 with low-temperature sintering characteristic and preparation method thereof Download PDFInfo
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- CN103319177A CN103319177A CN201310253737XA CN201310253737A CN103319177A CN 103319177 A CN103319177 A CN 103319177A CN 201310253737X A CN201310253737X A CN 201310253737XA CN 201310253737 A CN201310253737 A CN 201310253737A CN 103319177 A CN103319177 A CN 103319177A
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- tungstate
- microwave dielectric
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- 239000000919 ceramic Substances 0.000 title claims abstract description 16
- 238000002360 preparation method Methods 0.000 title claims abstract description 8
- 238000009766 low-temperature sintering Methods 0.000 title abstract 2
- 239000000843 powder Substances 0.000 claims abstract description 11
- 238000005245 sintering Methods 0.000 claims abstract description 9
- PBYZMCDFOULPGH-UHFFFAOYSA-N tungstate Chemical compound [O-][W]([O-])(=O)=O PBYZMCDFOULPGH-UHFFFAOYSA-N 0.000 claims abstract description 8
- 239000011230 binding agent Substances 0.000 claims abstract description 7
- 239000012298 atmosphere Substances 0.000 claims abstract description 6
- 239000000126 substance Substances 0.000 claims abstract description 6
- 238000000748 compression moulding Methods 0.000 claims abstract description 4
- 239000004372 Polyvinyl alcohol Substances 0.000 claims abstract description 3
- 238000000498 ball milling Methods 0.000 claims abstract description 3
- 239000012153 distilled water Substances 0.000 claims abstract description 3
- 229920002451 polyvinyl alcohol Polymers 0.000 claims abstract description 3
- 239000002994 raw material Substances 0.000 claims abstract description 3
- 239000002904 solvent Substances 0.000 claims abstract description 3
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 3
- 229910010413 TiO 2 Inorganic materials 0.000 claims description 6
- 238000005469 granulation Methods 0.000 claims description 2
- 230000003179 granulation Effects 0.000 claims description 2
- 229910010293 ceramic material Inorganic materials 0.000 abstract description 6
- 238000000034 method Methods 0.000 abstract description 4
- 239000000203 mixture Substances 0.000 abstract description 2
- GWEVSGVZZGPLCZ-UHFFFAOYSA-N Titan oxide Chemical compound O=[Ti]=O GWEVSGVZZGPLCZ-UHFFFAOYSA-N 0.000 abstract 2
- AYJRCSIUFZENHW-UHFFFAOYSA-L barium carbonate Chemical compound [Ba+2].[O-]C([O-])=O AYJRCSIUFZENHW-UHFFFAOYSA-L 0.000 abstract 2
- ZNOKGRXACCSDPY-UHFFFAOYSA-N tungsten(VI) oxide Inorganic materials O=[W](=O)=O ZNOKGRXACCSDPY-UHFFFAOYSA-N 0.000 abstract 1
- 239000000463 material Substances 0.000 description 9
- 238000004891 communication Methods 0.000 description 6
- 238000005516 engineering process Methods 0.000 description 5
- 238000011161 development Methods 0.000 description 3
- 239000000758 substrate Substances 0.000 description 3
- 239000002131 composite material Substances 0.000 description 2
- 239000011521 glass Substances 0.000 description 2
- 238000002844 melting Methods 0.000 description 2
- 230000008018 melting Effects 0.000 description 2
- 238000011160 research Methods 0.000 description 2
- 229910000906 Bronze Inorganic materials 0.000 description 1
- 229910020068 MgAl Inorganic materials 0.000 description 1
- 229910052779 Neodymium Inorganic materials 0.000 description 1
- 229910052777 Praseodymium Inorganic materials 0.000 description 1
- 206010037660 Pyrexia Diseases 0.000 description 1
- 229910052772 Samarium Inorganic materials 0.000 description 1
- 238000002441 X-ray diffraction Methods 0.000 description 1
- 238000004458 analytical method Methods 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 239000010974 bronze Substances 0.000 description 1
- 239000003985 ceramic capacitor Substances 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 229910052802 copper Inorganic materials 0.000 description 1
- KUNSUQLRTQLHQQ-UHFFFAOYSA-N copper tin Chemical compound [Cu].[Sn] KUNSUQLRTQLHQQ-UHFFFAOYSA-N 0.000 description 1
- 239000003989 dielectric material Substances 0.000 description 1
- 238000011156 evaluation Methods 0.000 description 1
- 239000002241 glass-ceramic Substances 0.000 description 1
- 230000001965 increasing effect Effects 0.000 description 1
- 229910052746 lanthanum Inorganic materials 0.000 description 1
- 229910052745 lead Inorganic materials 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- 238000010295 mobile communication Methods 0.000 description 1
- 229910052709 silver Inorganic materials 0.000 description 1
- 229910052718 tin Inorganic materials 0.000 description 1
- WFKWXMTUELFFGS-UHFFFAOYSA-N tungsten Chemical compound [W] WFKWXMTUELFFGS-UHFFFAOYSA-N 0.000 description 1
- 229910052721 tungsten Inorganic materials 0.000 description 1
- 239000010937 tungsten Substances 0.000 description 1
- 229910052726 zirconium Inorganic materials 0.000 description 1
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- Inorganic Insulating Materials (AREA)
- Compositions Of Oxide Ceramics (AREA)
Abstract
The invention discloses tungstate microwave dielectric ceramic Ba3WTiO8 with a low-temperature sintering characteristic and a preparation method thereof. The composition of the tungstate microwave dielectric ceramic material is Ba3WTiO8. The method comprises the following steps that: firstly, original powder of BaCO3, WO3 and TiO2 with the purity being higher than 99.9 percent is weighed and mixed according to a chemical formula of BaCu2V2O8; secondly, the raw materials are subjected to wet ball milling and mixed for 12 hours, and are pre-sintered for 6 hours in a 600 DEG C atmosphere after being dried, wherein distilled water serves as a solvent; thirdly, after a binder is added for pelleting, compression molding is performed, and finally, sintering is performed for 4 hours in a 1000-1030 DEG C atmosphere, wherein a polyvinyl alcohol solution with the mass concentration of 5 percent is adopted as the binder, and the amount of the binder is 3 percent of the total mass of the powder. The ceramic prepared through the method is properly sintered at 1000 to 1030 DEG C, has the dielectric constant of 17 to 18, the quality factor QF of 75000 to 96000 GHz and a low temperature coefficient of resonance frequency, can be co-fired with Cu electrodes at low temperature, and has great industrial application value.
Description
Technical field
The present invention relates to dielectric ceramic material, particularly relate to microwave dielectric ceramic material of the microwave devices such as medium substrate, resonator and wave filter that use in microwave frequency and preparation method thereof.
Background technology
Microwave dielectric ceramic refers to and is applied in microwave frequency band (being mainly UHF, SHF frequency range) circuit as dielectric material and completes the pottery of one or more functions, be widely used as the components and parts such as resonator, wave filter, dielectric substrate and medium guided wave loop in modern communication, it is the key foundation material of modern communication technology, at aspects such as portable mobile phone, automobile telephone, cordless telephone, telestar susceptor and military radars, very important application is arranged, in the miniaturization of modern communication instrument, integrated process, just bringing into play increasing effect.
Be applied to the dielectric ceramic of microwave frequency band, should meet the requirement of following dielectric characteristics: (1) seriation DIELECTRIC CONSTANT ε
rto adapt to the requirement of different frequency and different application occasion; (2) high quality factor q value or dielectric loss tan δ are to reduce noise, general requirement Qf>=3000 GHz; (3) the temperature factor τ of resonant frequency
?the as far as possible little thermostability to guarantee that device has had, general requirement-10/ ℃≤τ
?≤+10 ppm/ ℃.From late 1930s, just someone attempts dielectric substance is applied to microwave technology in the world.
According to relative permittivity ε
rsize from use the different of frequency range, usually the microwave-medium ceramics be developed He developing can be divided into to 4 classes.
(1) ultralow dielectric microwave dielectric ceramic, main representative is Al
2o
3-TiO
2, Y
2baCuO
5, MgAl
2o
4and Mg
2siO
4deng, its ε
r≤ 20, quality factor q * f>=50000GHz, τ
?≤ 10 ppm/ ° C.Be mainly used in microwave base plate and high-end microwave device.
(2) low ε
rwith the microwave dielectric ceramic of high Q value, be mainly BaO-MgO-Ta
2o
5, BaO-ZnO-Ta
2o
5or BaO-MgO-Nb
2o
5, BaO-ZnO-Nb
2o
5system or the composite system MWDC material between them.Its ε
r=25～30, Q=(1～2) * 10
4(under f>=10 GHz), τ
?≈ 0.Be mainly used in the microwave communication equipments such as direct broadcasting satellite of f >=8 GHz as the dielectric resonance device.
(3) medium ε
rwith the microwave dielectric ceramic of Q value, be mainly with BaTi
4o
9, Ba
2ti
9o
20(Zr, Sn) TiO
4deng the MWDC material that is base, its ε
r=35 ~ 40, Q=(6～9) * 10
3(f=3～-4GHz under), τ
?≤ 5 ppm/ ° C.Be mainly used in the interior microwave military radar of 4～8 GHz range of frequency and communication system as the dielectric resonance device.
(4) high ε
rand the lower microwave dielectric ceramic of Q value is mainly used in civilian mobile communcations system in 0.8～4GHz range of frequency, this is also the emphasis of microwave dielectric ceramic research.Since the eighties, the people such as Kolar, Kato find and have studied perovskite-like tungsten bronze type BaO-Ln in succession
2o
3-TiO
2series (Ln=La, Sm, Nd or Pr etc. are called for short BLT system), complex perovskite structure CaO-Li
2o-Ln
2o
3-TiO
2series, lead base series material, Ca
1-xln
2x/3tiO
3be contour ε
rmicrowave dielectric ceramic, the wherein BaO-Nd of BLT system
2o
3-TiO
2material dielectric constant reaches 90, lead base series (Pb, Ca) ZrO
3specific inductivity reaches 105.
The sintering temperature of above these material systems is generally higher than 1300 ° of C, can not be directly and the low melting point metals such as Ag and Cu burn altogether the formation laminated ceramic capacitor.In recent years, along with LTCC Technology (Low Temperature Co-fired Ceramics, the requirement of development LTCC) and the development of microwave multilayer device, researchist both domestic and external has carried out exploring widely and studying to some low fever's system materials, mainly to adopt devitrified glass or glass-ceramic composite system, because low melting glass has relatively high dielectric loss mutually, the existence of glassy phase has improved the dielectric loss of material greatly.Therefore development is the emphasis of current research without the low fired microwave dielectric ceramic material of glassy phase.
Summary of the invention
The purpose of this invention is to provide a kind of have low-loss and good thermostability, tungstate microwave dielectric ceramic material that sintering temperature is low simultaneously and preparation method thereof.
The chemical constitution formula of tungstate microwave dielectric ceramic material of the present invention is: Ba
3wTiO
8.
Preparation method's concrete steps of described tungstate ceramics are:
(1) by purity, be the BaCO more than 99.9%
3, WO
3and TiO
2starting powder press Ba
3wTiO
8the chemical formula weigh batching.
(2) step (1) raw material wet ball-milling is mixed 12 hours, solvent is distilled water, pre-burning 6 hours in 600 ℃ of air atmosphere after oven dry.
(3) after adding binding agent granulation in the powder made in step (2), then compression moulding, last sintering 4 hours in 1000 ~ 1030 ℃ of air atmosphere; Described binding agent adopts the polyvinyl alcohol solution that mass concentration is 5%, and dosage accounts for 3% of powder total mass.
Pottery prepared by the present invention is good at 650-680 ℃ of sintering, its specific inductivity reaches 17～18, and quality factor q f value is up to 75000-96000GHz, and temperature coefficient of resonance frequency is little, and can be low temperature co-fired with the Cu electrode, therefore industrial great using value arranged.
Embodiment
Embodiment:
Table 1 shows 4 specific embodiments and the microwave dielectric property thereof that forms different sintering temperatures of the present invention.Its preparation method as mentioned above, carries out the evaluation of microwave dielectric property by the cylindrical dielectric resonator method; By powder with the Cu powder that accounts for powder quality 20%, mix, after compression moulding, 1000 ℃ of lower sintering 4 hours; X ray diffraction material phase analysis and scanning electron microscopic observation all show Ba
3wTiO
8with Cu, chemical reaction, i.e. Ba do not occur
3wTiO
8can be low temperature co-fired with the Cu electrode.
The present invention never is limited to above embodiment.The bound of sintering temperature, interval value can realize the present invention, at this, do not enumerate embodiment.
This pottery can be widely used in the manufacture of the microwave devices such as various medium substrates, resonator and wave filter, can meet the Technology Need of the systems such as mobile communication, satellite communications.
Table 1:
Claims (1)
1. but a tungstate, as the application of low-temperature sintered microwave dielectric ceramic, is characterized in that the chemical constitution formula of described tungstate is: Ba
3wTiO
8;
Preparation method's concrete steps of described tungstate are:
(1) by purity, be the BaCO more than 99.9%
3, WO
3and TiO
2starting powder press Ba
3wTiO
8the chemical formula weigh batching;
(2) step (1) raw material wet ball-milling is mixed 12 hours, solvent is distilled water, pre-burning 6 hours in 600 ℃ of air atmosphere after oven dry;
(3) after adding binding agent granulation in the powder made in step (2), then compression moulding, last sintering 4 hours in 1000 ~ 1030 ℃ of air atmosphere; Described binding agent adopts the polyvinyl alcohol solution that mass concentration is 5%, and dosage accounts for 3% of powder total mass.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201310253737.XA CN103319177B (en) | 2013-06-25 | 2013-06-25 | Microwave dielectric ceramic Ba3WTiO8 with low-temperature sintering characteristic and preparation method thereof |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201310253737.XA CN103319177B (en) | 2013-06-25 | 2013-06-25 | Microwave dielectric ceramic Ba3WTiO8 with low-temperature sintering characteristic and preparation method thereof |
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| Publication Number | Publication Date |
|---|---|
| CN103319177A true CN103319177A (en) | 2013-09-25 |
| CN103319177B CN103319177B (en) | 2014-07-30 |
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ID=49188276
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|---|---|---|---|
| CN201310253737.XA Active CN103319177B (en) | 2013-06-25 | 2013-06-25 | Microwave dielectric ceramic Ba3WTiO8 with low-temperature sintering characteristic and preparation method thereof |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103496981A (en) * | 2013-09-26 | 2014-01-08 | 桂林理工大学 | Low-temperature sintering temperature-stable microwave dielectric ceramic Bi14W2O27 and preparation method thereof |
| CN106242559A (en) * | 2016-08-01 | 2016-12-21 | 桂林理工大学 | A kind of titanate SrCr3inTi2o11application as temperature-stable microwave dielectric ceramic |
| CN107586123A (en) * | 2017-10-22 | 2018-01-16 | 桂林理工大学 | A kind of high-quality factor microwave medium ceramic material and preparation method thereof |
| CN116656359A (en) * | 2023-05-31 | 2023-08-29 | 广西大学 | Tungsten titanate matrix material for rare earth fluorescent powder, fluorescent material and preparation method of fluorescent material |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH06243724A (en) * | 1993-02-15 | 1994-09-02 | Matsushita Electric Ind Co Ltd | Dielectric ceramic and coaxial type resonator and antenna shared unit |
| CN101823880A (en) * | 2010-06-04 | 2010-09-08 | 西安交通大学 | Phenacite type molybdenum-based and tungsten-based ultralow temperature sintered microwave dielectric ceramic materials and preparation method thereof |
-
2013
- 2013-06-25 CN CN201310253737.XA patent/CN103319177B/en active Active
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH06243724A (en) * | 1993-02-15 | 1994-09-02 | Matsushita Electric Ind Co Ltd | Dielectric ceramic and coaxial type resonator and antenna shared unit |
| CN101823880A (en) * | 2010-06-04 | 2010-09-08 | 西安交通大学 | Phenacite type molybdenum-based and tungsten-based ultralow temperature sintered microwave dielectric ceramic materials and preparation method thereof |
Non-Patent Citations (1)
| Title |
|---|
| B. MöSSNER ET AL.: "9R-STAPELVARIANTEN VOM TYP Ba3(B,B’)2O9-y MIT B,B’≡Mo，W，V，Ti", 《JOURNAL OF THE LESS-COMMON METALS》, vol. 114, no. 2, 31 December 1985 (1985-12-31) * |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103496981A (en) * | 2013-09-26 | 2014-01-08 | 桂林理工大学 | Low-temperature sintering temperature-stable microwave dielectric ceramic Bi14W2O27 and preparation method thereof |
| CN106242559A (en) * | 2016-08-01 | 2016-12-21 | 桂林理工大学 | A kind of titanate SrCr3inTi2o11application as temperature-stable microwave dielectric ceramic |
| CN107586123A (en) * | 2017-10-22 | 2018-01-16 | 桂林理工大学 | A kind of high-quality factor microwave medium ceramic material and preparation method thereof |
| CN116656359A (en) * | 2023-05-31 | 2023-08-29 | 广西大学 | Tungsten titanate matrix material for rare earth fluorescent powder, fluorescent material and preparation method of fluorescent material |
| CN116656359B (en) * | 2023-05-31 | 2024-04-09 | 广西大学 | Tungsten titanate matrix material for rare earth fluorescent powder, fluorescent material and preparation method of fluorescent material |
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| CN103319177B (en) | 2014-07-30 |
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