CN110885243B - Low-dielectric-constant aluminate microwave dielectric ceramic material and preparation method thereof - Google Patents
Low-dielectric-constant aluminate microwave dielectric ceramic material and preparation method thereof Download PDFInfo
- Publication number
- CN110885243B CN110885243B CN201911198591.7A CN201911198591A CN110885243B CN 110885243 B CN110885243 B CN 110885243B CN 201911198591 A CN201911198591 A CN 201911198591A CN 110885243 B CN110885243 B CN 110885243B
- Authority
- CN
- China
- Prior art keywords
- caal
- aluminate
- powder
- microwave
- ball milling
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- 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
- C04B35/44—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 aluminates
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
- C04B35/622—Forming processes; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
- C04B35/622—Forming processes; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
- C04B35/64—Burning or sintering processes
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- 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
- C04B2235/3205—Alkaline earth oxides or oxide forming salts thereof, e.g. beryllium oxide
- C04B2235/3208—Calcium oxide or oxide-forming salts thereof, e.g. lime
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- 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
- C04B2235/65—Aspects relating to heat treatments of ceramic bodies such as green ceramics or pre-sintered ceramics, e.g. burning, sintering or melting processes
- C04B2235/656—Aspects relating to heat treatments of ceramic bodies such as green ceramics or pre-sintered ceramics, e.g. burning, sintering or melting processes characterised by specific heating conditions during heat treatment
- C04B2235/6562—Heating rate
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- 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
- C04B2235/65—Aspects relating to heat treatments of ceramic bodies such as green ceramics or pre-sintered ceramics, e.g. burning, sintering or melting processes
- C04B2235/656—Aspects relating to heat treatments of ceramic bodies such as green ceramics or pre-sintered ceramics, e.g. burning, sintering or melting processes characterised by specific heating conditions during heat treatment
- C04B2235/6567—Treatment time
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Ceramic Engineering (AREA)
- Manufacturing & Machinery (AREA)
- Materials Engineering (AREA)
- Structural Engineering (AREA)
- Organic Chemistry (AREA)
- Inorganic Chemistry (AREA)
- Inorganic Insulating Materials (AREA)
- Compositions Of Oxide Ceramics (AREA)
Abstract
The invention belongs to the technical field of ceramic materials, and particularly relates to an aluminate microwave dielectric ceramic material with a low dielectric constant and a preparation method thereof, wherein the preparation method mainly comprises the following steps: proportioning, primary ball milling, presintering, secondary ball milling, granulating, tabletting and sintering. The chemical expression of the aluminate microwave dielectric ceramic prepared by the invention is as follows: CaAl4O7The main raw material is CaCO3，Al2O3. CaAl synthesized by regulating sintering temperature of ceramic4O7The ceramic has stable performance and excellent microwave dielectric performance, and has great application value in components and parts of wireless communication equipment such as microwave substrates, microwave filters and the like.
Description
Technical Field
The invention belongs to the technical field of ceramic materials, and particularly relates to an aluminate microwave dielectric ceramic material with a low dielectric constant and a preparation method thereof.
Background
With the rapid development of wireless communication technology and the gradual exhaustion of microwave low-frequency band resources, the frequency band used for wireless communication is gradually expanding from the ISM frequency band to the millimeter wave frequency band. In order to meet the communication requirement of the millimeter wave frequency band, the dielectric constant (epsilon) is lowr<10) And a high quality factor (Qf)>15000GHz) has attracted considerable attention as a research and development of passive devices such as dielectric resonators, filters, substrates, and microstrip lines. Low epsilonrThe delay of microwave signal transmission can be reduced, and the signal response and transmission speed of the microwave device are improved; the high Qf value can enhance the frequency-selective characteristic of the device and reduce the energy transfer loss. In recent years, with the increasing requirements of people on information transmission content, speed, quality and the like, a new generation of high-frequency communication technology such as 5G mobile communication, an internet of things (IoT) technology and the like are emerging. Therefore, there is a need to develop a batch of high quality microwave dielectric ceramic materials with low dielectric constant.
From dielectric theory, it is known that the dielectric constant of a material is mainly determined by the ionic polarizability per unit volume. Therefore, the aluminate ceramics are formed of Al3+Lower ionic polarizability
And have been considered to be promising low dielectric constant material systems. CaAl4O7Ceramics are widely applied to high-temperature refractory materials, but the microwave dielectric property of the ceramics has not been researched yet.
Disclosure of Invention
Based on the defects in the prior art, the invention provides an aluminate microwave dielectric ceramic material with low dielectric constant and a preparation method thereof.
A preparation method of low dielectric constant aluminate microwave dielectric ceramic material comprises the following steps:
(1) preparing materials: raw material CaCO3And Al2O3According to the stoichiometric ratio of 1: 2, preparing materials;
(2) mixing materials: mixing the raw materials, ball milling beads and absolute ethyl alcohol according to the proportion of 1: 1: 2, placing the mixture in a ball mill for wet ball milling for 24 hours to obtain slurry raw materials;
(3) drying: putting the slurry raw material obtained in the step (2) into an oven to be dried to constant weight;
(4) pre-burning: sieving and dispersing the powder obtained in the step (3), and then placing the powder in a high-temperature furnace for presintering for 3 hours at the presintering temperature of 1050 and 1200 ℃ to generate CaAl4O7A compound;
(5) secondary ball milling: the CaAl generated in the step (4)4O7The compound is placed in a ball mill for ball milling to form CaAl4O7Sizing agent;
(6) secondary drying: the CaAl in the step (5)4O7Placing the slurry in an oven to dry to constant weight;
(7) and (3) granulation: sieving the powder obtained in the step (6), and then mixing the powder with an adhesive according to a ratio of 94: 6, uniformly mixing the components in percentage by mass;
(8) tabletting: pressing and molding the powder uniformly mixed in the step (7) to obtain a cylindrical green body;
(9) and (3) sintering: and (4) sintering the green body obtained in the step (8), and finally cooling to room temperature along with the furnace to obtain the aluminate microwave dielectric ceramic material with the low dielectric constant.
Preferably, the preparation method further comprises the following steps:
(10) and (3) post-processing: and (4) grinding and polishing the low-dielectric-constant aluminate microwave dielectric ceramic material sintered in the step (9) to make the surface flat and smooth.
Preferably, the pressure of the press molding in the step (8) is 100-200 MPa.
Preferably, the sintering process in the step (9) includes: heating to 650 ℃ at the speed of 5 ℃/min, keeping the temperature for 2h, then continuously heating to 1500-1600 ℃ at the speed of 5 ℃/min, keeping the temperature for 3h, and finally cooling to 1100 ℃ at the speed of 1 ℃/min.
Preferably, the raw material CaCO is added before the material preparation3And Al2O3Grinding is carried out for 24 h.
Preferably, the raw material CaCO3And Al2O3The purity of (A) was 99.99%.
Preferably, the ball mill is a planetary ball mill.
Preferably, the pre-firing temperature in the step (4) is 1200 ℃.
Preferably, the diameter of the cylindrical green body is 12mm, and the height of the cylindrical green body is 5 mm.
The invention also provides the low dielectric constant aluminate microwave dielectric ceramic material prepared by the preparation method of any scheme, and the dielectric constant epsilon is within the microwave frequency ranger6.6-8.7, and the quality factor Qf value is 14097-25533GHz, thus having great application value in the fields of millimeter wave communication and the like.
Compared with the prior art, the invention has the beneficial effects that:
the low dielectric constant aluminate microwave dielectric ceramic material prepared by the invention has the raw material price (CaCO)3And Al2O3) Low cost, simple preparation process and low production cost.
By designing different sintering temperatures, the microwave dielectric ceramic material with low dielectric constant (6.6-8.7) and better quality factor (25533GHz) can be stably obtained. The ceramic can be widely applied to components of wireless communication equipment such as microwave substrates and the like, and has great application value.
Drawings
FIG. 1 shows CaAl of example 1 of the present invention4O7XRD diffraction patterns of ceramic materials;
FIG. 2 shows CaAl of an embodiment of the present invention4O7The change curve of the dielectric constant of the ceramic material along with the sintering temperature;
FIG. 3 shows CaAl of an embodiment of the present invention4O7Graph of ceramic material quality factor as a function of sintering temperature.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more clearly understood, the following method and technical solutions are further described with reference to the accompanying drawings and specific embodiments, but should not be construed as limiting the present invention.
Example 1:
the preparation method of the low dielectric constant aluminate microwave dielectric ceramic material comprises the following steps:
(1) preparing materials: raw material CaCO3And Al2O3Proportioning according to the stoichiometric ratio in the chemical expression; specifically, 15.3995g of CaCO was weighed in order3And 31.3758gAl2O3The raw materials of (1); raw material CaCO3And Al2O3The purity of (A) is 99.99%;
(2) mixing materials: pouring the raw materials into a ball mill, wherein the raw materials, ball milling beads and absolute ethyl alcohol are mixed according to the proportion of 1: 1: 2, placing the mixture in a ball mill for wet ball milling for 24 hours to obtain slurry raw materials;
(3) drying: drying the slurry in a 70 ℃ oven to obtain a dry mixture;
(4) pre-burning: passing the dried powder through a 100-target standardDispersing by a sieve, then presintering for 3 hours in a high temperature furnace at the presintering temperature of 1200 ℃ to enable the powder to react primarily to generate CaAl4O7A compound;
(5) secondary ball milling: the CaAl synthesized by the preliminary reaction4O7Ball milling the compound in a ball mill for 24h to form finely dispersed CaAl4O7Sizing agent;
(6) secondary drying: drying the slurry in a 70 ℃ oven to obtain dry CaAl4O7A compound powder;
(7) and (3) granulation: taking CaAl4O7The powder was sieved through a 100 mesh sieve, after which the powder was mixed with a binder (polyvinyl alcohol PVA) according to a 94: 6, uniformly mixing the components in percentage by mass;
(8) tabletting: putting the powder obtained by granulation into a die, and pressing the powder into a cylindrical green body under the pressure of 200 MPa; the diameter of the cylindrical green body is 12mm, and the height of the cylindrical green body is 5 mm;
(9) and (3) sintering: heating the green body obtained in the step (8) to 650 ℃ at the speed of 5 ℃/min, preserving heat for 2h, then continuously heating to 1500 ℃ at the speed of 5 ℃/min, preserving heat for 3h, then cooling to 1100 ℃ at the speed of 1 ℃/min, and finally cooling to room temperature along with the furnace;
(10) and (3) post-processing: and (4) grinding and polishing the ceramic sintered in the step (9) to obtain a ceramic sample with a smooth surface.
FIG. 1 is an XRD diffraction pattern of the ceramic sample of this example, illustrating that the ceramic sample obtained is CaAl4O7. The XRD diffraction pattern of the low dielectric constant aluminate microwave dielectric ceramic material of the following example is the same as that of the present example.
Example 2:
the preparation method of the low dielectric constant aluminate microwave dielectric ceramic material comprises the following steps:
(1) preparing materials: raw material CaCO3And Al2O3Proportioning according to the stoichiometric ratio in the chemical expression; specifically, 15.3995g of CaCO was weighed in order3And 31.3758gAl2O3The raw materials of (1); raw material CaCO3And Al2O3The purity of (A) is 99.99%;
(2) mixing materials: pouring the raw materials into a ball mill, wherein the raw materials, ball milling beads and absolute ethyl alcohol are mixed according to the proportion of 1: 1: 2, placing the mixture in a ball mill for wet ball milling for 24 hours to obtain slurry raw materials;
(3) drying: drying the slurry in a 70 ℃ oven to obtain a dry mixture;
(4) pre-burning: dispersing the dried powder through a standard sieve of 100 meshes, then presintering the powder in a high-temperature furnace for 3 hours at the presintering temperature of 1200 ℃ to enable the powder to react initially to generate CaAl4O7A compound;
(5) secondary ball milling: the CaAl synthesized by the preliminary reaction4O7Ball milling the compound in a ball mill for 24h to form finely dispersed CaAl4O7Sizing agent;
(6) secondary drying: drying the slurry in a 70 ℃ oven to obtain dry CaAl4O7A compound powder;
(7) and (3) granulation: taking CaAl4O7The powder was sieved through a 100 mesh sieve, after which the powder was mixed with a binder (polyvinyl alcohol PVA) according to a 94: 6, uniformly mixing the components in percentage by mass;
(8) tabletting: putting the powder obtained by granulation into a die, and pressing the powder into a cylindrical green body under the pressure of 200 MPa; the diameter of the cylindrical green body is 12mm, and the height of the cylindrical green body is 5 mm;
(9) and (3) sintering: heating the green body obtained in the step (8) to 650 ℃ at the speed of 5 ℃/min, preserving heat for 2h, then continuously heating to 1525 ℃ at the speed of 5 ℃/min, preserving heat for 3h, then cooling to 1100 ℃ at the speed of 1 ℃/min, and finally cooling to room temperature along with the furnace;
(10) and (3) post-processing: and (4) grinding and polishing the ceramic sintered in the step (9) to obtain a ceramic sample with a smooth surface.
Example 3:
the preparation method of the low dielectric constant aluminate microwave dielectric ceramic material comprises the following steps:
(1) preparing materials: raw material CaCO3And Al2O3Proportioning according to the stoichiometric ratio in the chemical expression; specifically, 15.3995g of CaCO was weighed in order3And 31.3758gAl2O3The raw materials of (1); raw material CaCO3And Al2O3The purity of (A) is 99.99%;
(2) mixing materials: pouring the raw materials into a ball mill, wherein the raw materials, ball milling beads and absolute ethyl alcohol are mixed according to the proportion of 1: 1: 2, placing the mixture in a ball mill for wet ball milling for 24 hours to obtain slurry raw materials;
(3) drying: drying the slurry in a 70 ℃ oven to obtain a dry mixture;
(4) pre-burning: dispersing the dried powder through a standard sieve of 100 meshes, then presintering the powder in a high-temperature furnace for 3 hours at the presintering temperature of 1200 ℃ to enable the powder to react initially to generate CaAl4O7A compound;
(5) secondary ball milling: the CaAl synthesized by the preliminary reaction4O7Ball milling the compound in a ball mill for 24h to form finely dispersed CaAl4O7Sizing agent;
(6) secondary drying: drying the slurry in a 70 ℃ oven to obtain dry CaAl4O7A compound powder;
(7) and (3) granulation: taking CaAl4O7The powder was sieved through a 100 mesh sieve, after which the powder was mixed with a binder (polyvinyl alcohol PVA) according to a 94: 6, uniformly mixing the components in percentage by mass;
(8) tabletting: putting the powder obtained by granulation into a die, and pressing the powder into a cylindrical green body under the pressure of 200 MPa; the diameter of the cylindrical green body is 12mm, and the height of the cylindrical green body is 5 mm;
(9) and (3) sintering: heating the green body obtained in the step (8) to 650 ℃ at the speed of 5 ℃/min, preserving heat for 2h, then continuously heating to 1550 ℃ at the speed of 5 ℃/min, preserving heat for 3h, then cooling to 1100 ℃ at the speed of 1 ℃/min, and finally cooling to room temperature along with the furnace;
(10) and (3) post-processing: and (4) grinding and polishing the ceramic sintered in the step (9) to obtain a ceramic sample with a smooth surface.
Example 4:
the preparation method of the low dielectric constant aluminate microwave dielectric ceramic material comprises the following steps:
(1) ingredients: raw material CaCO3And Al2O3Proportioning according to the stoichiometric ratio in the chemical expression; specifically, 15.3995g of CaCO was weighed in order3And 31.3758gAl2O3The raw materials of (1); raw material CaCO3And Al2O3The purity of (A) is 99.99%;
(2) mixing materials: pouring the raw materials into a ball mill, wherein the raw materials, ball milling beads and absolute ethyl alcohol are mixed according to the proportion of 1: 1: 2, placing the mixture in a ball mill for wet ball milling for 24 hours to obtain slurry raw materials;
(3) drying: drying the slurry in a 70 ℃ oven to obtain a dry mixture;
(4) pre-burning: dispersing the dried powder through a standard sieve of 100 meshes, then presintering the powder in a high-temperature furnace for 3 hours at the presintering temperature of 1200 ℃ to enable the powder to react initially to generate CaAl4O7A compound;
(5) secondary ball milling: the CaAl synthesized by the preliminary reaction4O7Ball milling the compound in a ball mill for 24h to form finely dispersed CaAl4O7Sizing agent;
(6) secondary drying: drying the slurry in a 70 ℃ oven to obtain dry CaAl4O7A compound powder;
(7) and (3) granulation: taking CaAl4O7The powder was sieved through a 100 mesh sieve, after which the powder was mixed with a binder (polyvinyl alcohol PVA) according to a 94: 6, uniformly mixing the components in percentage by mass;
(8) tabletting: putting the powder obtained by granulation into a die, and pressing the powder into a cylindrical green body under the pressure of 200 MPa; the diameter of the cylindrical green body is 12mm, and the height of the cylindrical green body is 5 mm;
(9) and (3) sintering: heating the green body obtained in the step (8) to 650 ℃ at the speed of 5 ℃/min, preserving heat for 2h, then continuously heating to 1575 ℃ at the speed of 5 ℃/min, preserving heat for 3h, then cooling to 1100 ℃ at the speed of 1 ℃/min, and finally cooling to room temperature along with the furnace;
(10) and (3) post-processing: and (4) grinding and polishing the ceramic sintered in the step (9) to obtain a ceramic sample with a smooth surface.
Example 5:
the preparation method of the low dielectric constant aluminate microwave dielectric ceramic material comprises the following steps:
(1) preparing materials: raw material CaCO3And Al2O3Proportioning according to the stoichiometric ratio in the chemical expression; specifically, 15.3995g of CaCO was weighed in order3And 31.3758gAl2O3The raw materials of (1); raw material CaCO3And Al2O3The purity of (A) is 99.99%;
(2) mixing materials: pouring the raw materials into a ball mill, wherein the raw materials, ball milling beads and absolute ethyl alcohol are mixed according to the proportion of 1: 1: 2, placing the mixture in a ball mill for wet ball milling for 24 hours to obtain slurry raw materials;
(3) drying: drying the slurry in a 70 ℃ oven to obtain a dry mixture;
(4) pre-burning: dispersing the dried powder through a standard sieve of 100 meshes, then presintering the powder in a high-temperature furnace for 3 hours at the presintering temperature of 1200 ℃ to enable the powder to react initially to generate CaAl4O7A compound;
(5) secondary ball milling: the CaAl synthesized by the preliminary reaction4O7Ball milling the compound in a ball mill for 24h to form finely dispersed CaAl4O7Sizing agent;
(6) secondary drying: drying the slurry in a 70 ℃ oven to obtain dry CaAl4O7A compound powder;
(7) and (3) granulation: taking CaAl4O7The powder was sieved through a 100 mesh sieve, after which the powder was mixed with a binder (polyvinyl alcohol PVA) according to a 94: 6, uniformly mixing the components in percentage by mass;
(8) tabletting: putting the powder obtained by granulation into a die, and pressing the powder into a cylindrical green body under the pressure of 200 MPa; the diameter of the cylindrical green body is 12mm, and the height of the cylindrical green body is 5 mm;
(9) and (3) sintering: heating the green body obtained in the step (8) to 650 ℃ at the speed of 5 ℃/min, preserving heat for 2h, then continuously heating to 1600 ℃ at the speed of 5 ℃/min, preserving heat for 3h, then cooling to 1100 ℃ at the speed of 1 ℃/min, and finally cooling to room temperature along with the furnace;
(10) and (3) post-processing: and (4) grinding and polishing the ceramic sintered in the step (9) to obtain a ceramic sample with a smooth surface.
And (3) grinding and polishing the surface of the sample by using the cylindrical dielectric prepared in the embodiment 1-5 by using metallographic abrasive paper until no obvious scratch can be observed by naked eyes. Respectively testing the dielectric constant epsilon of the sample by adopting a network analyzer after the sample is ultrasonically vibrated and cleanedrAnd the quality factor Qf value, the resulting performance as a function of sintering temperature is shown in FIGS. 2 and 3.
TABLE 1 CaAl of examples 1-54O7Epsilon of ceramics at different sintering temperaturesrAnd Qf value
| Sintering temperature (. degree. C.) | εr | Qf(GHz) |
| 1500 (example 1) | 6.6 | 14097 |
| 1525 (example 2) | 7.83 | 17250 |
| 1550 (example 3) | 8.25 | 21854 |
| 1575 (example 4) | 8.45 | 25533 |
| 1600 (example 5) | 8.7 | 24503 |
Table 1 shows CaAl produced by the production method of the present invention4O7Epsilon of ceramics at different sintering temperaturesrAnd Qf values. As is clear from Table 1, the lowest dielectric constant was obtained in example 1 and the value thereof was 6.6, and the best quality factor was obtained in example 4 and the value thereof was 25533 GHz.
The ball mill of the above embodiment is preferably a planetary ball mill.
In the above embodiments and alternatives, the pre-firing temperature may also be 1050 ℃, 1100 ℃, 1150 ℃, 1180 ℃, etc.
In the above-described examples and alternatives thereof, the pressure of the press molding in the step (8) is 100MPa, 120MPa, 150MPa, 180MPa, or the like.
In the above examples and their alternatives, the raw CaCO is added before the batching3And Al2O3Grinding is carried out for 24 hours, and the uniformity of raw material particles is ensured.
The above description of the embodiments is only intended to facilitate the understanding of the method of the invention and its core ideas. It should be noted that, for those skilled in the art, it is possible to make various improvements and modifications to the present invention without departing from the principle of the present invention, and those improvements and modifications also fall within the scope of the claims of the present invention.
Claims (9)
1. A preparation method of low dielectric constant aluminate microwave dielectric ceramic material is characterized by comprising the following steps:
(1) preparing materials: raw material CaCO3And Al2O3According to the stoichiometric ratio of 1: 2, preparing materials;
(2) mixing materials: mixing the raw materials, ball milling beads and absolute ethyl alcohol according to the proportion of 1: 1: 2, placing the mixture in a ball mill for wet ball milling for 24 hours to obtain slurry raw materials;
(3) drying: putting the slurry raw material obtained in the step (2) into an oven to be dried to constant weight;
(4) pre-burning: sieving and dispersing the powder obtained in the step (3), and then placing the powder in a high-temperature furnace for presintering for 3 hours at the presintering temperature of 1050 and 1200 ℃ to generate CaAl4O7A compound;
(5) secondary ball milling: the CaAl generated in the step (4)4O7The compound is placed in a ball mill for ball milling to form CaAl4O7Sizing agent;
(6) secondary drying: the CaAl in the step (5)4O7Placing the slurry in an oven to dry to constant weight;
(7) and (3) granulation: sieving the powder obtained in the step (6), and then mixing the powder with an adhesive according to a ratio of 94: 6, uniformly mixing the components in percentage by mass;
(8) tabletting: pressing and molding the powder uniformly mixed in the step (7) to obtain a cylindrical green body;
(9) and (3) sintering: sintering the green body obtained in the step (8), and finally cooling the green body to room temperature along with a furnace to obtain the aluminate microwave dielectric ceramic material with the low dielectric constant;
the sintering process in the step (9) comprises the following steps: heating to 650 ℃ at the speed of 5 ℃/min, preserving heat for 2h, then continuously heating to 1500-;
dielectric constant epsilon in microwave frequency ranger6.6 to 8.7.
2. The method of claim 1, further comprising the steps of:
(10) and (3) post-processing: and (4) grinding and polishing the low-dielectric-constant aluminate microwave dielectric ceramic material sintered in the step (9) to make the surface flat and smooth.
3. The production method according to claim 1, wherein the pressure for the press molding in the step (8) is 100-200 MPa.
4. The method of claim 1, wherein the raw CaCO is added before the compounding3And Al2O3Grinding is carried out for 24 h.
5. The method for preparing as claimed in claim 1, wherein the raw CaCO3And Al2O3The purity of (A) was 99.99%.
6. The production method according to claim 1, wherein the ball mill is a planetary ball mill.
7. The method of claim 1, wherein the pre-firing temperature in the step (4) is 1200 ℃.
8. The method of claim 1, wherein the cylindrical green compact has a diameter of 12mm and a height of 5 mm.
9. The aluminate microwave dielectric ceramic material with low dielectric constant prepared by the preparation method as claimed in any one of claims 1 to 8, wherein the quality factor Qf value is 14097-25533GHz in the microwave frequency band.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911198591.7A CN110885243B (en) | 2019-11-29 | 2019-11-29 | Low-dielectric-constant aluminate microwave dielectric ceramic material and preparation method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911198591.7A CN110885243B (en) | 2019-11-29 | 2019-11-29 | Low-dielectric-constant aluminate microwave dielectric ceramic material and preparation method thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN110885243A CN110885243A (en) | 2020-03-17 |
| CN110885243B true CN110885243B (en) | 2022-03-01 |
Family
ID=69749382
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201911198591.7A Active CN110885243B (en) | 2019-11-29 | 2019-11-29 | Low-dielectric-constant aluminate microwave dielectric ceramic material and preparation method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN110885243B (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111592348A (en) * | 2020-05-28 | 2020-08-28 | 杭州电子科技大学 | Low-dielectric-constant microwave dielectric ceramic with excellent temperature stability and preparation method thereof |
| CN113666722B (en) * | 2021-09-06 | 2022-07-12 | 中国科学院上海硅酸盐研究所 | Low-temperature sintered microwave dielectric material and preparation method thereof |
| CN118084483B (en) * | 2024-04-29 | 2024-07-09 | 山东理工大学 | BST-based microwave dielectric adjustable composite ceramic material and preparation method thereof |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1476616A (en) * | 2000-11-20 | 2004-02-18 | �ձ�������ҵ��ʽ���� | Microwave dielectric procelain composition and dielectric resonator |
| CN101077784A (en) * | 2006-05-26 | 2007-11-28 | 中国科学院金属研究所 | Nano CaAl4O7 material and preparing method thereof |
| CN101077785A (en) * | 2006-05-26 | 2007-11-28 | 中国科学院金属研究所 | Nano CaAl4O7 material and preparing method thereof |
| CN101870584A (en) * | 2010-05-12 | 2010-10-27 | 西安交通大学 | Molybdenum-based ultralow-temperature sintering microwave medium ceramic materials and preparation method thereof |
-
2019
- 2019-11-29 CN CN201911198591.7A patent/CN110885243B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1476616A (en) * | 2000-11-20 | 2004-02-18 | �ձ�������ҵ��ʽ���� | Microwave dielectric procelain composition and dielectric resonator |
| CN101077784A (en) * | 2006-05-26 | 2007-11-28 | 中国科学院金属研究所 | Nano CaAl4O7 material and preparing method thereof |
| CN101077785A (en) * | 2006-05-26 | 2007-11-28 | 中国科学院金属研究所 | Nano CaAl4O7 material and preparing method thereof |
| CN101870584A (en) * | 2010-05-12 | 2010-10-27 | 西安交通大学 | Molybdenum-based ultralow-temperature sintering microwave medium ceramic materials and preparation method thereof |
Non-Patent Citations (1)
| Title |
|---|
| Crystal structure, infrared reflectivity spectra and microwave;Bing Liu等;《Journal of Alloys and Compounds》;20190630;全文 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN110885243A (en) | 2020-03-17 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN110885243B (en) | Low-dielectric-constant aluminate microwave dielectric ceramic material and preparation method thereof | |
| CN111592348A (en) | Low-dielectric-constant microwave dielectric ceramic with excellent temperature stability and preparation method thereof | |
| CN111517789B (en) | Low-dielectric microwave dielectric ceramic material and preparation method thereof | |
| CN101260001A (en) | High-Q microwave dielectric ceramic material and preparing method thereof | |
| WO2019113973A1 (en) | Dielectric ceramic material and preparation method therefor | |
| CN112876251A (en) | High-performance low-dielectric microwave ceramic prepared based on cold sintering technology and method | |
| CN113233889A (en) | Calcium-neodymium-titanium microwave dielectric ceramic and preparation method thereof | |
| CN112266232A (en) | Low-dielectric microwave dielectric ceramic material suitable for 5G millimeter wave communication application and preparation method thereof | |
| CN113563052A (en) | Borate-based low-dielectric microwave dielectric ceramic and preparation method thereof | |
| CN106747435B (en) | A kind of preparation method for the core-shell structure microwave-medium ceramics that temperature is stable | |
| CN104944940A (en) | Stable-temperature magnesium-titanate-base microwave dielectric ceramic and preparation method thereof | |
| CN110818419B (en) | Microwave dielectric ceramic LiF and preparation method thereof | |
| CN110845226A (en) | Microwave dielectric ceramic material SrGa2O4And method for preparing the same | |
| CN111908897B (en) | MgO-based microwave ceramic dielectric material and preparation method thereof | |
| CN105819832A (en) | Beryllium oxide/silicon carbide ceramic composite microwave attenuation ceramic and preparation method thereof | |
| CN111187062B (en) | CaSnSiO5-K2MoO4Base composite ceramic microwave material and preparation method thereof | |
| CN107253856A (en) | A kind of microwave dielectric material of near-zero resonance frequency temperature coefficient and preparation method thereof | |
| CN114736012B (en) | Low dielectric microwave dielectric ceramic with ultrahigh Q value and LTCC material thereof | |
| CN113387695A (en) | Low-dielectric high-quality microwave dielectric ceramic for 5G communication and preparation method thereof | |
| CN111018524B (en) | Low-loss trigonal tungstate-based microwave dielectric ceramic and preparation method thereof | |
| CN114180949A (en) | Ceramic material and preparation method thereof, and ceramic sintered body and preparation method thereof | |
| CN111943670B (en) | LiWVO 6 -K 2 MoO 4 Base composite ceramic microwave material and preparation method thereof | |
| CN111960821B (en) | Microwave dielectric ceramic material and preparation method and application thereof | |
| CN110746188B (en) | Microwave dielectric ceramic composition, preparation method and application thereof, microwave dielectric ceramic, preparation method and application thereof, and microwave device | |
| CN110627480B (en) | MgO-Al2O3-GeO2Preparation method of ternary system microwave dielectric material |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant | ||
| TR01 | Transfer of patent right | ||
| TR01 | Transfer of patent right |
Effective date of registration: 20221219 Address after: 230000 B-2704, wo Yuan Garden, 81 Ganquan Road, Shushan District, Hefei, Anhui. Patentee after: HEFEI LONGZHI ELECTROMECHANICAL TECHNOLOGY Co.,Ltd. Address before: 310018 no.1158, No.2 street, Baiyang street, Hangzhou Economic and Technological Development Zone, Zhejiang Province Patentee before: HANGZHOU DIANZI University |
|
| TR01 | Transfer of patent right | ||
| TR01 | Transfer of patent right |
Effective date of registration: 20230620 Address after: Floor 1, 15 #, No. 36, Dalian East Road, Taicang City, Suzhou City, Jiangsu Province, 215400 Patentee after: Super Precision (Suzhou) Aviation Precision Machinery Manufacturing Co.,Ltd. Address before: 230000 B-2704, wo Yuan Garden, 81 Ganquan Road, Shushan District, Hefei, Anhui. Patentee before: HEFEI LONGZHI ELECTROMECHANICAL TECHNOLOGY Co.,Ltd. |