CN106542819A - A kind of intermediary's microwave-medium ceramics and preparation method thereof - Google Patents
A kind of intermediary's microwave-medium ceramics and preparation method thereof Download PDFInfo
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- CN106542819A CN106542819A CN201510604798.5A CN201510604798A CN106542819A CN 106542819 A CN106542819 A CN 106542819A CN 201510604798 A CN201510604798 A CN 201510604798A CN 106542819 A CN106542819 A CN 106542819A
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Abstract
The present invention relates to a kind of intermediary's microwave-medium ceramics and preparation method thereof, intermediary's microwave-medium ceramics consist of Ca0.1Sr0.4La0.5Al0.5Ti0.5O3, the dielectric constant of intermediary's microwave-medium ceramics is 31～36, and quality factor q f is 30000～35500GHz, and temperature coefficient of resonance frequency is 1ppm/ DEG C～5ppm/ DEG C.Preparation method is comprised the following steps：（1）By CaCO3、SrCO3、TiO2、La2O3, and Al2O3By metering than dispensing, ball milling, dry, sieve, 4h is incubated in 1350 DEG C～1450 DEG C carries out pre-burning, the powder of pre-burning is carried out secondary ball milling, dries, sieves, add binding agent and granulated, it is pressed into cylinder idiosome, 4～12h sintering is incubated at 1500～1600 DEG C, you can the intermediary's microwave-medium ceramics needed for obtaining.It is preparation process is simple, with low cost.
Description
Technical field
The invention belongs to microwave-medium ceramics technical field, and in particular to a kind of microwave dielectric ceramic with medium dielectric constant and its system
Preparation Method.
Background technology
In recent years, developing rapidly with mechanics of communication, it is also growing to the demand of microwave device.Microwave-medium is made pottery
Porcelain has the advantages that lossy microwave is low, dielectric constant is high and frequency-temperature coefficient is little, can both meet communication equipment mobility,
Portability, miniaturization, the requirement of miniaturization, can meet again and there is high-performance, high reliability operating characteristic to want in microwave range
Ask, obtain extensive concern.
The microwave dielectric ceramic with medium dielectric constant being applied in microwave system, its Essential Performance Requirements is：Dielectric constant
εr=30～60, temperature coefficient of resonance frequency τf=-5～5ppm/ DEG C, Qf >=5000GHz.LaAlO3With high quality factor
Permittivity εrWith negative temperature coefficient of resonance frequency τf(Qf=68000GHz, εr=23,) can pass through
Ca of the addition with larger positive temperature coefficient of resonance frequency0.2Sr0.8TiO3() adjust.S-Y Cho etc. are studied
(1-x)LaAlO3-xSrTiO3The microwave dielectric property of system ceramics.0.5LaAlO is obtained3—0.5SrTiO3Ceramics evidence has excellent
Good microwave dielectric property：εr=35, Qf=28000GHz and τf=15ppm/ DEG C.
The content of the invention
For the disadvantages described above of prior art, it is an object of the present invention to provide in a kind of process is simple, stable performance
Dielectric microwave media ceramic and preparation method thereof.The microwave-medium ceramics of the present invention, preparation process is simple, repeatability are good and micro-
Ripple dielectric properties are excellent.
Here, the present invention provides a kind of intermediary's microwave-medium ceramics, intermediary's microwave-medium ceramics are consisted of
Ca0.1Sr0.4La0.5Al0.5Ti0.5O3, the dielectric constant of intermediary's microwave-medium ceramics is 31～36, and quality factor q f is
30000～35500GHz, temperature coefficient of resonance frequency are 1ppm/ DEG C～5.0ppm/ DEG C.
In the present invention, in a preferred version, the dielectric constant of intermediary's microwave-medium ceramics is 31～34.Another
In one preferred version, the dielectric constant of intermediary's microwave-medium ceramics is 31.3～35.6.
Also, the quality factor q f of intermediary's microwave-medium ceramics is 30400-34800Ghz.
Also, in a preferred version, the temperature coefficient of resonance frequency of intermediary's microwave-medium ceramics is 1.2ppm/ DEG C～
5.0ppm/℃.In another preferred embodiment, the temperature coefficient of resonance frequency of intermediary's microwave-medium ceramics be 1ppm/ DEG C～
3ppm/℃。
The present invention also provides a kind of preparation method of intermediary's microwave-medium ceramics, and the preparation method includes：
Step 1) by chemical raw material CaCO3、SrCO3、TiO2、La2O3, and Al2O3Ca is pressed respectively0.1Sr0.4La0.5Al0.5Ti0.5O3
Chemical formula weigh dispensing；
Step 2) by step 1) the chemical raw material mixing that configured, first time ball milling 12～24 hours, drying sieve；
Step 3) by step 2) in the powder that is well mixed in 1350 DEG C～1450 DEG C pre-burning 4-6 hours, preferably 4 hours；
Step 4) by step 3) powder after calcining, carry out second ball milling 6～12 hours, drying, in the powder of drying plus
Enter polyvinyl alcohol as binding agent and granulate, be pressed into cylindric idiosome；
Step 5) by step 4) obtained by cylindric idiosome be incubated 4～12 hours at 1500～1600 DEG C and sinter porcelain into, obtain
Intermediary's microwave-medium ceramics.
In the present invention, adopt CaCO3、SrCO3、TiO2、La2O3, and Al2O3By metering than dispensing, ball milling, baking
Do, sieve, pre-burning, the powder of pre-burning is carried out secondary ball milling, dries, sieves, add PVA (polyvinyl alcohol) binding agent simultaneously
Granulated, be pressed into cylinder idiosome, sintered, obtain intermediary's microwave-medium ceramics.Prepared intermediary's microwave-medium pottery performance
It is stable, have the advantages that quality factor are high, dielectric constant is high and frequency-temperature coefficient is little.The present invention preparation process is simple, into
This is cheap, has broad application prospects.
In the present invention, step 1) described in raw materials of Ca CO3、SrCO3、TiO2、La2O3, and Al2O3Purity be
More than 99.9%.
In the present invention, step 4) in the weight/mass percentage composition of binding agent polyvinyl alcohol be 6%～8%, concentration is 6%.
Also, the abrading-ball that first time ball milling and/or second ball milling are adopted is for zirconia ball, ball-milling medium is deionized water.
In the present invention, in first time ball milling, raw mixture：Zirconia ball：The mass ratio of deionized water is 1：2：2.
Powder in the present invention, in second ball milling, after the calcining：Zirconia ball：The mass ratio of deionized water is 1：
2：2.
Description of the drawings
Fig. 1 is the SEM image of intermediary's microwave-medium ceramics ceramics of the synthesis of example 1.
Specific embodiment
The present invention is further illustrated below in conjunction with accompanying drawing and following embodiments, it should be appreciated that following embodiments are only used for
The bright present invention, and the unrestricted present invention.
The invention provides a kind of intermediary's microwave-medium ceramics, with quality factor height, dielectric constant height and frequency temperature system
The advantages of number is little.
Intermediary's microwave-medium ceramics of the present invention, its raw material is constituted and its mole percent level is
Ca0.1Sr0.4La0.5Al0.5Ti0.5O3, using SrCO3、TiO2、La2O3, and Al2O3As raw material.
The present invention also provides a kind of preparation method of intermediary's microwave-medium ceramics, and the preparation method process is simple, repeatability are good
It is good, and microwave dielectric property is excellent.
The preparation method of the present invention includes：
(1) by chemical raw material CaCO3、SrCO3、TiO2、La2O3, and Al2O3Ca is pressed respectively0.1Sr0.4La0.5Al0.5Ti0.5O3Change
Formula weighs dispensing；
(2) the chemical raw material mixing for having configured step (1), is put in ball grinder, by raw mixture：Zirconia ball：Go from
The mass ratio of sub- water is 1：2：2 ratio adds zirconia ball and deionized water.Ball milling 12～24 hours, after ball milling
Dry in raw material and drying box, sieve, wherein, the aperture sieved is 20 mesh；
(3) powder for being well mixed step (2) calcines 4-6 hours at 1350 DEG C～1450 DEG C；
(4) powder after step (3) calcining is put in ball grinder by the powder after calcining：Zirconia ball：The quality of deionized water
Than for 1：2：2 ratio adds zirconia ball and deionized water, ball milling 6～12 hours, drying to add in the powder of drying
Enter polyvinyl alcohol that the concentration that weight/mass percentage composition is 6%～8% is 6% as binding agent and granulate, be pressed into cylindrical embryo
Body；
(5) cylindric idiosome obtained by step (4) is incubated into 4～12 hours at 1500～1600 DEG C and sinters porcelain into, in acquisition
Dielectric microwave media ceramic；
(6) with the microwave dielectric property of intermediary's microwave-medium ceramics obtained in Network Analyzer testing procedure (5).
Wherein, raw materials of Ca CO3、SrCO3、TiO2、La2O3, and Al2O3Purity be more than 99.9%.
In the preparation method of the present invention, the abrading-ball that first time ball milling and/or second ball milling are adopted for zirconia ball, ball milling Jie
Matter is deionized water.
The calcined temperature of the present invention is 1350 DEG C～1450 DEG C, and temperature retention time is 4-6h.
In the preparation method of the present invention, the weight/mass percentage composition of binding agent polyvinyl alcohol is 6%～8%, and concentration is 6%.
It is 4～12 hours that the sintering temperature of the present invention is 1500 DEG C～1600 DEG C temperature retention times.
Also, the tester in step (6) is Network Analyzer.
The invention has the beneficial effects as follows, there is provided a kind of Ca0.1Sr0.4La0.5Al0.5Ti0.5O3Intermediary's microwave dielectric ceramic materials, its
1500～1600 DEG C of sintering temperature, dielectric constant be 31～36, quality factor be 30000～35500GHz, resonant frequency temperature
Degree coefficient is 1ppm/ DEG C～5ppm/ DEG C.Additionally, the preparation process is simple, process is pollution-free, with low cost, with wide
Application prospect.
Enumerate embodiment further below to describe the present invention in detail.It will similarly be understood that following examples are served only for this
Bright to be further described, it is impossible to be interpreted as limiting the scope of the invention, those skilled in the art is of the invention
Some nonessential modifications and adaptations that the above is made belong to protection scope of the present invention.The specific technique ginseng of following examples
Number etc. is also only an example in OK range, i.e. those skilled in the art can be done in suitable scope by the explanation of this paper
Select, and do not really want to be defined in the concrete numerical value of hereafter example.
Embodiment
1) CaCO that purity is 99.9% is weighed respectively3、SrCO3、TiO2、La2O3, and Al2O3：1.00gCaCO3、
5.91gSrCO3、3.99gTiO2、8.14gLa2O3, and 2.55gAl2O3, add raw materials into after mixing in nylon tank, add
43.18 grams of zirconia balls and 43.2ml deionized waters, ball milling, drying are sieved；
2) powder being well mixed is calcined 4 hours at 1350 DEG C～1450 DEG C；
3) powder after calcining is put in ball grinder and adds 43.18 grams of zirconia balls and 43.2ml deionized waters, ball milling, drying,
To in the powder of drying add weight/mass percentage composition to be polyvinyl alcohol that 8% concentration is 6% as binding agent and granulate, be pressed into
Cylindric idiosome；
4) sinter cylindric idiosome into porcelain, the intermediary's microwave-medium ceramics needed for obtaining；
5) with the microwave dielectric property of intermediary's microwave-medium ceramics obtained in Network Analyzer testing procedure 4.
The test result of the related process parameters and microwave dielectric property of specific embodiment refers to table 1.
Table 1：
The diameter and thickness of sample uses miking.
By Agilent E8363A PNA Network Analyzers, using cylindrical ceramic material prepared by the measurement of open type parallel plate method
The dielectric constant of material, test furniture is put into ESPEC MC-710F type high/low temperature circulating boxes carries out temperature coefficient of resonance frequency
Measurement, temperature range are 20～80 DEG C of test frequencies in the range of 5.1～2.5GHz.
Using the quality factor of cylindrical ceramic sample prepared by the measurement of enclosed cell method, test frequency is in 9～10GHz scopes
It is interior.
Industrial applicability：The preparation process is simple, with low cost of the present invention, has broad application prospects.
Claims (10)
1. a kind of intermediary's microwave-medium ceramics, it is characterised in that intermediary's microwave-medium ceramics consist of Ca0.1Sr0.4La0.5Al0.5Ti0.5O3, the dielectric constant of intermediary's microwave-medium ceramics is 31～36, and quality factor q f is 30000～35500GHz, and temperature coefficient of resonance frequency is 1ppm/ DEG C～5ppm/ DEG C.
2. intermediary's microwave-medium ceramics according to claim 1, it is characterised in that the dielectric constant of intermediary's microwave-medium ceramics is 31～34.
3. intermediary's microwave-medium ceramics according to claim 1 and 2, it is characterised in that the quality factor q f of intermediary's microwave-medium ceramics is 30400-34800Ghz.
4. intermediary's microwave-medium ceramics according to any one of claims 1 to 3, it is characterised in that temperature coefficient of resonance frequency is 1ppm/ DEG C～3ppm/ DEG C.
5. a kind of preparation method of the intermediary's microwave-medium ceramics according to any one of Claims 1 to 4, it is characterised in that the preparation method includes：
Step 1）By chemical raw material CaCO3、SrCO3、TiO2、La2O3, and Al2O3Ca is pressed respectively0.1Sr0.4La0.5Al0.5Ti0.5O3Chemical formula weigh dispensing；
Step 2）By step 1）The chemical raw material mixing for having configured, first time ball milling 12～24 hours, drying sieve；
Step 3）By step 2）In the powder that is well mixed in 1350 DEG C～1450 DEG C pre-burnings 4～6 hours；
Step 4）By step 3）Powder after calcining, carries out second ball milling 6～12 hours, drying, adds that polyvinyl alcohol is as binding agent and granulates in the powder of drying, is pressed into cylindric idiosome；
Step 5）By step 4）Obtained cylindric idiosome at 1500～1600 DEG C is incubated 4～12 hours and sinters porcelain into, obtains intermediary's microwave-medium ceramics.
6. preparation method according to claim 5, it is characterised in that step 1）Described in raw materials of Ca CO3、SrCO3、TiO2、La2O3, and Al2O3Purity be more than 99.9%.
7. according to the preparation method any one of claim 5 or 6, it is characterised in that step 4）The weight/mass percentage composition of middle binding agent polyvinyl alcohol is 6%～8%, and concentration is 6%.
8. according to the preparation method any one of claim 5～7, it is characterised in that for zirconia ball, ball-milling medium is deionized water to the abrading-ball that first time ball milling and/or second ball milling are adopted.
9. according to the preparation method described in claim 8, it is characterised in that in first time ball milling, raw mixture：Zirconia ball：The mass ratio of deionized water is 1：2：2.
10. according to the preparation method described in claim 8, it is characterised in that the powder in second ball milling, after the calcining：Zirconia ball：The mass ratio of deionized water is 1：2：2.
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| CN108059455A (en) * | 2018-02-02 | 2018-05-22 | 华中科技大学 | A kind of intermediary's high-quality τfNearly zero microwave-medium ceramics and preparation method thereof |
| CN112919894A (en) * | 2021-03-10 | 2021-06-08 | 嘉兴佳利电子有限公司 | Frequency-stable low-dielectric microwave dielectric ceramic material and preparation method thereof |
| CN113480303A (en) * | 2021-07-27 | 2021-10-08 | 华中科技大学温州先进制造技术研究院 | Aluminate-based low-dielectric microwave dielectric ceramic and preparation method thereof |
| CN113831122A (en) * | 2021-10-09 | 2021-12-24 | 西北工业大学 | Temperature-stable low-loss medium microwave dielectric ceramic and preparation method thereof |
| CN114315343A (en) * | 2021-12-15 | 2022-04-12 | 广东通宇通讯股份有限公司 | Microwave dielectric material with high Q value and medium dielectric constant and preparation method thereof |
| CN116217225A (en) * | 2023-03-10 | 2023-06-06 | 湖北大学 | Strontium titanate-based microwave dielectric ceramic material and preparation method thereof |
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