Summary of the invention
The object of the invention is to satisfy the needs of communications electronics Circuits System technical development for requirement on devices, provide a kind of low-k and microwave property good near-zero resonance frequency temperature coefficient silicate microwave dielectric ceramic materials, the method for this microwave dielectric ceramic materials of preparation is provided simultaneously.
The thing of microwave dielectric ceramic materials of the present invention comprises Mg mutually
2SiO
4And MgCaSiO
4, wherein composition MgO, CaO, SiO
2Mol ratio be MgO: CaO: SiO
2=2 * (1-x): 2x: 1,0.1≤x≤0.6; This microwave dielectric ceramic materials specific inductivity is 6.81~9.10, and quality factor (Q * f value) are 17,510~24,170GHz, temperature coefficient of resonance frequency be-14ppm/ ℃~+ 11ppm/ ℃.
The concrete steps that prepare this microwave dielectric ceramic materials method are as follows:
Step (1) raw material is chosen: choose purity greater than 99% MgO, CaO and SiO
2As raw material;
Step (2) batching and batch mixing: with raw material MgO: CaO: SiO in molar ratio
2=2 * (1-x): 2x: 1,0.1≤x≤0.6 weighing mix the back in ball mill with agate as abrading-ball, deionized water as grinding medium, oven dry in the drying baker is inserted in wet grinding after 12~24 hours, bake out temperature is 80~120 ℃;
Step (3) calcining and granulation: the powder after will drying is crossed the accurate nylon mesh of 200 targets, and powder is uniformly dispersed, and calcines then 2~4 hours, and calcining temperature is 1000~1250 ℃, and powder fully reacts synthetic compound; To calcine the back powder then and add deionized water carry out 12~24 hours form slurry of wet grinding second time again in ball mill, will insert in the drying baker through the slurry after the wet grinding for the second time and dry, bake out temperature is 80~120 ℃, formation secondary powder; The secondary powder is crossed the accurate nylon mesh of 200 targets again, added organic binder bond PVA (polyvinyl alcohol) after the secondary powder is uniformly dispersed, the amount that adds polyvinyl alcohol is 4~8Wt% of secondary powder total mass, through old, mist projection granulating powdered particulate material;
Step (4) compression moulding: the powder particle material is inserted in the powder pressure forming machine, under 98~100MPa pressure, be pressed into right cylinder;
Step (5) sinters porcelain into: the right cylinder that is pressed into 1375 ℃~1450 ℃ sintering temperatures 2~4 hours, then with the speed temperature control cooling of 2~5 ℃ of per minutes, is closed the temperature regulating device furnace cooling after arriving 1175 ℃~1250 ℃;
Step (6) later stage mechanical workout: the ceramic grinding that sinters is polished to finished product.
[concrete grammar is referring to document: B.W.Hakki for dielectric resonant chamber method test specific inductivity that employing Hakki and Coleman proposes and microwave property, and P.D.Coleman, " DielectricResonator Method of Measuring Inductive Capacities in the MillimeterRange; " IEEE Trans.Microw.Theory Technol., MTT-8,402-10 (1970)], this microwave dielectric ceramic materials is with respect to the specific inductivity of other materials lower (6.8~9.1), and comprehensive microwave property is good.
Silicate systems pottery provided by the invention has been filled up specific inductivity blank as the dielectric material of microwave and millimeter wave media ceramic device temperature good stability between 6~10.And this ceramic microwave is functional: quality factor are 17,510~24,170GHz, temperature coefficient of resonance frequency be-14ppm/ ℃~+ 11ppm/ ℃ scope in.This dielectric material its frequency stabilization under operating ambient temperature is good, is not easy to drift about; And the quality factor height, so its frequency-selecting is good and signal transmission quality is also high; Moreover the MgTiO of the current report of permittivity ratio
3-TiO
2With Al
2O
3-TiO
2The complex phase ceramic specific inductivity is lower, thereby the response of signal and transmission speed are also faster.
Microwave dielectric ceramic materials provided by the invention enriches the demand of current high-frequency communication electronic circuit technology to the good low-dielectric constant dielectric medium material of operating ambient temperature good stability and frequency selectivity well, is well suited for using as the material of multiplayer microwave resonator, oscillator filter, microwave antenna, microwave wire and microwave base plate in the electronic circuit system and electronic circuit board device.
Embodiment
A kind of thing of microwave dielectric ceramic materials comprises Mg mutually
2SiO
4And MgCaSiO
4, wherein composition MgO, CaO, SiO
2Mol ratio be MgO: CaO: TiO
2=2 * (1-x): 2x: 1,0.1≤x≤0.6; This microwave dielectric ceramic materials DIELECTRIC CONSTANT
rBe 6.81~9.10, quality factor (Q * f value) are 17,510~24,170GHz, temperature coefficient of resonance frequency τ
fFor-14ppm/ ℃~+ 11ppm/ ℃.The method such as the following specific embodiment that prepare this microwave dielectric ceramic materials.
Embodiment 1.
Step (1) raw material is chosen: choose purity greater than 99% MgO, CaO and SiO
2As raw material;
Step (2) batching and batch mixing: with raw material MgO: CaO: SiO in molar ratio
2=18: weighing in 2: 10 mix the back in ball mill with agate as abrading-ball, deionized water as grinding medium, oven dry in the drying baker is inserted in wet grinding after 24 hours, bake out temperature is 80 ℃;
Step (3) calcining and granulation: the powder after will drying is crossed the accurate nylon mesh of 200 targets, and powder is uniformly dispersed, and calcines then 2 hours, and calcining temperature is 1250 ℃, and powder fully reacts synthetic compound; To calcine the back powder then and add deionized water carry out 24 hours form slurry of wet grinding second time again in ball mill, will insert in the drying baker through the slurry after the wet grinding for the second time and dry, bake out temperature is 80 ℃, formation secondary powder; The secondary powder is crossed the accurate nylon mesh of 200 targets again, added organic binder bond PVA after the secondary powder is uniformly dispersed, the amount that adds PVA is the 4Wt% of secondary powder total mass, through old, mist projection granulating powdered particulate material;
Step (4) compression moulding: the powder particle material is inserted in the powder pressure forming machine, under 98MPa pressure, be pressed into right cylinder;
Step (5) sinters porcelain into: the right cylinder that is pressed into 1375 ℃ of sintering temperatures 4 hours, then with the speed temperature control cooling of 2 ℃ of per minutes, is closed the temperature regulating device furnace cooling after arriving 1175 ℃;
Step (6) later stage mechanical workout: the ceramic grinding that sinters is polished to finished product.
The thing of the microwave dielectric ceramic materials of making comprises Mg mutually
2SiO
4And MgCaSiO
4, content is respectively 98.3Wt% and 1.7Wt%, its microwave dielectric property: at resonant frequency f
0Be 15.196GHz test down, DIELECTRIC CONSTANT
rBe 6.90, quality factor q * f is 22,450GHz, temperature coefficient of resonance frequency τ
fBe-14ppm/ ℃.
Embodiment 2.
Step (1) raw material is chosen: choose purity greater than 99% MgO, CaO and SiO
2As raw material;
Step (2) batching and batch mixing: with raw material MgO: CaO: SiO in molar ratio
2=16: weighing in 4: 10 mix the back in ball mill with agate as abrading-ball, deionized water as grinding medium, oven dry in the drying baker is inserted in wet grinding after 20 hours, bake out temperature is 90 ℃;
Step (3) calcining and granulation: the powder after will drying is crossed the accurate nylon mesh of 200 targets, and powder is uniformly dispersed, and calcines then 2.5 hours, and calcining temperature is 1200 ℃, and powder fully reacts synthetic compound; To calcine the back powder then and add deionized water carry out 20 hours form slurry of wet grinding second time again in ball mill, will insert in the drying baker through the slurry after the wet grinding for the second time and dry, bake out temperature is 90 ℃, formation secondary powder; The secondary powder is crossed the accurate nylon mesh of 200 targets again, added organic binder bond PVA after the secondary powder is uniformly dispersed, the amount that adds PVA is the 5Wt% of secondary powder total mass, through old, mist projection granulating powdered particulate material;
Step (4) compression moulding: the powder particle material is inserted in the powder pressure forming machine, under 98MPa pressure, be pressed into right cylinder;
Step (5) sinters porcelain into: the right cylinder that is pressed into 1400 ℃ of sintering temperatures 3 hours, then with the speed temperature control cooling of 3 ℃ of per minutes, is closed the temperature regulating device furnace cooling after arriving 1200 ℃;
Step (6) later stage mechanical workout: the ceramic grinding that sinters is polished to finished product.
The thing of the microwave dielectric ceramic materials of making comprises Mg mutually
2SiO
4And MgCaSiO
4, content is respectively 94.8Wt% and 5.2Wt%, its microwave dielectric property: at resonant frequency f
0Be 15.664GHz test down, DIELECTRIC CONSTANT
rBe 6.81, quality factor q * f is 21,700GHz, temperature coefficient of resonance frequency τ
fBe-12ppm/ ℃.
Embodiment 3.
Step (1) raw material is chosen: choose purity greater than 99% MgO, CaO and SiO
2As raw material;
Step (2) batching and batch mixing: with raw material MgO: CaO: TiO in molar ratio
2=14: weighing in 6: 10 mix the back in ball mill with agate as abrading-ball, deionized water as grinding medium, oven dry in the drying baker is inserted in wet grinding after 18 hours, bake out temperature is 100 ℃;
Step (3) calcining and granulation: the powder after will drying is crossed the accurate nylon mesh of 200 targets, and powder is uniformly dispersed, and calcines then 3 hours, and calcining temperature is 1150 ℃, and powder fully reacts synthetic compound; To calcine the back powder then and add deionized water carry out 18 hours form slurry of wet grinding second time again in ball mill, will insert in the drying baker through the slurry after the wet grinding for the second time and dry, bake out temperature is 100 ℃, formation secondary powder; The secondary powder is crossed the accurate nylon mesh of 200 targets again, added organic binder bond PVA after the secondary powder is uniformly dispersed, the amount that adds PVA is the 6Wt% of secondary powder total mass, through old, mist projection granulating powdered particulate material;
Step (4) compression moulding: the powder particle material is inserted in the powder pressure forming machine, under 99MPa pressure, be pressed into right cylinder;
Step (5) sinters porcelain into: the right cylinder that is pressed into 1425 ℃ of sintering temperatures 2.5 hours, then with the speed temperature control cooling of 4 ℃ of per minutes, is closed the temperature regulating device furnace cooling after arriving 1225 ℃;
Step (6) later stage mechanical workout: the ceramic grinding that sinters is polished to finished product.
The thing of the microwave dielectric ceramic materials of making is Mg mutually
2SiO
4And MgCaSiO
4, content is respectively 68.9Wt% and 31.1Wt%, its microwave dielectric property: at resonant frequency f
0Be 14.422GHz test down, DIELECTRIC CONSTANT
rBe 7.55, quality factor q * f is 19,180GHz, temperature coefficient of resonance frequency τ
fBe-10ppm/ ℃.
Embodiment 4.
Step (1) raw material is chosen: choose purity greater than 99% MgO, CaO and SiO
2As raw material;
Step (2) batching and batch mixing: with raw material MgO: CaO: TiO in molar ratio
2=12: weighing in 8: 10 mix the back in ball mill with agate as abrading-ball, deionized water as grinding medium, oven dry in the drying baker is inserted in wet grinding after 16 hours, bake out temperature is 100 ℃;
Step (3) calcining and granulation: the powder after will drying is crossed the accurate nylon mesh of 200 targets, and powder is uniformly dispersed, and calcines then 3 hours, and calcining temperature is 1100 ℃, and powder fully reacts synthetic compound; To calcine the back powder then and add deionized water carry out 16 hours form slurry of wet grinding second time again in ball mill, will insert in the drying baker through the slurry after the wet grinding for the second time and dry, bake out temperature is 100 ℃, formation secondary powder; The secondary powder is crossed the accurate nylon mesh of 200 targets again, added organic binder bond PVA after the secondary powder is uniformly dispersed, the amount that adds PVA is the 7Wt% of secondary powder total mass, through old, mist projection granulating powdered particulate material;
Step (4) compression moulding: the powder particle material is inserted in the powder pressure forming machine, under 99MPa pressure, be pressed into right cylinder;
Step (5) sinters porcelain into: the right cylinder that is pressed into 1450 ℃ of sintering temperatures 2 hours, then with the speed temperature control cooling of 5 ℃ of per minutes, is closed the temperature regulating device furnace cooling after arriving 1250 ℃;
Step (6) later stage mechanical workout: the ceramic grinding that sinters is polished to finished product.
The thing of the microwave dielectric ceramic materials of making is Mg mutually
2SiO
4And MgCaSiO
4, content is respectively 26.1Wt% and 73.9Wt%, microwave dielectric property: at resonant frequency f
0Be 15.760GHz test down, DIELECTRIC CONSTANT
rBe 7.23, quality factor q * f is 24,170GHz, temperature coefficient of resonance frequency τ
fBe+5ppm/ ℃.
Embodiment 5.
Step (1) raw material is chosen: choose purity greater than 99% MgO, CaO and SiO
2As raw material;
Step (2) batching and batch mixing: with raw material MgO: CaO: TiO in molar ratio
2=1: weighing in 1: 1 mix the back in ball mill with agate as abrading-ball, deionized water as grinding medium, oven dry in the drying baker is inserted in wet grinding after 15 hours, bake out temperature is 110 ℃;
Step (3) calcining and granulation: the powder after will drying is crossed the accurate nylon mesh of 200 targets, and powder is uniformly dispersed, and calcines then 3.5 hours, and calcining temperature is 1050 ℃, and powder fully reacts synthetic compound; To calcine the back powder then and add deionized water carry out 15 hours form slurry of wet grinding second time again in ball mill, will insert in the drying baker through the slurry after the wet grinding for the second time and dry, bake out temperature is 110 ℃, formation secondary powder; The secondary powder is crossed the accurate nylon mesh of 200 targets again, added organic binder bond PVA after the secondary powder is uniformly dispersed, the amount that adds PVA is the 8Wt% of secondary powder total mass, through old, mist projection granulating powdered particulate material;
Step (4) compression moulding: the powder particle material is inserted in the powder pressure forming machine, under 100MPa pressure, be pressed into right cylinder;
Step (5) sinters porcelain into: the right cylinder that is pressed into 1400 ℃ of sintering temperatures 3 hours, then with the speed temperature control cooling of 3 ℃ of per minutes, is closed the temperature regulating device furnace cooling after arriving 1200 ℃;
Step (6) later stage mechanical workout: the ceramic grinding that sinters is polished to finished product.
The thing of the microwave dielectric ceramic materials of making is Mg mutually
2SiO
4And MgCaSiO
4, content is respectively 6.7Wt% and 93.3Wt%, at microwave dielectric property: at resonant frequency f
0For 15.724GHz detects down, DIELECTRIC CONSTANT
rBe 8.71, quality factor q * f is 18,010GHz, temperature coefficient of resonance frequency τ
fBe+3ppm/ ℃.
Embodiment 6.
Step (1) raw material is chosen: choose purity greater than 99% MgO, CaO and SiO
2As raw material;
Step (2) batching and batch mixing: with raw material MgO: CaO: TiO in molar ratio
2=8: weighing in 12: 10 mix the back in ball mill with agate as abrading-ball, deionized water as grinding medium, oven dry in the drying baker is inserted in wet grinding after 12 hours, bake out temperature is 120 ℃;
Step (3) calcining and granulation: the powder after will drying is crossed the accurate nylon mesh of 200 targets, and powder is uniformly dispersed, and calcines then 4 hours, and calcining temperature is 1000 ℃, and powder fully reacts synthetic compound; To calcine the back powder then and add deionized water carry out 12 hours form slurry of wet grinding second time again in ball mill, will insert in the drying baker through the slurry after the wet grinding for the second time and dry, bake out temperature is 120 ℃, formation secondary powder; The secondary powder is crossed the accurate nylon mesh of 200 targets again, added organic binder bond PVA after the secondary powder is uniformly dispersed, the amount that adds PVA is the 4Wt% of secondary powder total mass, through old, mist projection granulating powdered particulate material;
Step (4) compression moulding: the powder particle material is inserted in the powder pressure forming machine, under 100MPa pressure, be pressed into right cylinder;
Step (5) sinters porcelain into: the right cylinder that is pressed into 1425 ℃ of sintering temperatures 2.5 hours, then with the speed temperature control cooling of 4 ℃ of per minutes, is closed the temperature regulating device furnace cooling after arriving 1225 ℃;
Step (6) later stage mechanical workout: the ceramic grinding that sinters is polished to finished product.
The thing of the microwave dielectric ceramic materials of making is Mg mutually
2SiO
4And MgCaSiO
4, content is respectively 1.7Wt% and 98.3Wt%, microwave dielectric property: at resonant frequency f
0For 15.676GHz detects down, DIELECTRIC CONSTANT
rBe 9.10, quality factor q * f is 17,510GHz, temperature coefficient of resonance frequency τ
fBe+11ppm/ ℃.