CN111244628A - High-temperature-resistant broadband wave-transparent ceramic radome structure and preparation method thereof - Google Patents
High-temperature-resistant broadband wave-transparent ceramic radome structure and preparation method thereof Download PDFInfo
- Publication number
- CN111244628A CN111244628A CN202010187521.8A CN202010187521A CN111244628A CN 111244628 A CN111244628 A CN 111244628A CN 202010187521 A CN202010187521 A CN 202010187521A CN 111244628 A CN111244628 A CN 111244628A
- Authority
- CN
- China
- Prior art keywords
- layer
- homogeneous
- radome
- temperature
- ceramic
- 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.)
- Pending
Links
Images
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01Q—ANTENNAS, i.e. RADIO AERIALS
- H01Q1/00—Details of, or arrangements associated with, antennas
- H01Q1/42—Housings not intimately mechanically associated with radiating elements, e.g. radome
- H01Q1/422—Housings not intimately mechanically associated with radiating elements, e.g. radome comprising two or more layers of dielectric material
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B28—WORKING CEMENT, CLAY, OR STONE
- B28B—SHAPING CLAY OR OTHER CERAMIC COMPOSITIONS; SHAPING SLAG; SHAPING MIXTURES CONTAINING CEMENTITIOUS MATERIAL, e.g. PLASTER
- B28B1/00—Producing shaped prefabricated articles from the material
- B28B1/001—Rapid manufacturing of 3D objects by additive depositing, agglomerating or laminating of material
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B33—ADDITIVE MANUFACTURING TECHNOLOGY
- B33Y—ADDITIVE MANUFACTURING, i.e. MANUFACTURING OF THREE-DIMENSIONAL [3-D] OBJECTS BY ADDITIVE DEPOSITION, ADDITIVE AGGLOMERATION OR ADDITIVE LAYERING, e.g. BY 3-D PRINTING, STEREOLITHOGRAPHY OR SELECTIVE LASER SINTERING
- B33Y10/00—Processes of additive manufacturing
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B33—ADDITIVE MANUFACTURING TECHNOLOGY
- B33Y—ADDITIVE MANUFACTURING, i.e. MANUFACTURING OF THREE-DIMENSIONAL [3-D] OBJECTS BY ADDITIVE DEPOSITION, ADDITIVE AGGLOMERATION OR ADDITIVE LAYERING, e.g. BY 3-D PRINTING, STEREOLITHOGRAPHY OR SELECTIVE LASER SINTERING
- B33Y70/00—Materials specially adapted for additive manufacturing
-
- 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
- C04B35/515—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on non-oxide ceramics
- C04B35/58—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on non-oxide ceramics based on borides, nitrides, i.e. nitrides, oxynitrides, carbonitrides or oxycarbonitrides or silicides
- C04B35/584—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on non-oxide ceramics based on borides, nitrides, i.e. nitrides, oxynitrides, carbonitrides or oxycarbonitrides or silicides based on silicon nitride
-
- 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
- C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
- C04B2235/60—Aspects relating to the preparation, properties or mechanical treatment of green bodies or pre-forms
- C04B2235/602—Making the green bodies or pre-forms by moulding
- C04B2235/6026—Computer aided shaping, e.g. rapid prototyping
Abstract
The invention discloses a high-temperature-resistant broadband wave-transparent ceramic radome structure and a preparation method thereof. The high-temperature-resistant broadband wave-transmitting ceramic radome structure comprises a homogeneous outer layer, a porous layer, a homogeneous inner layer and a homogeneous connecting layer, and is integrally formed by adopting a single wave-transmitting ceramic material, uniformly distributed holes are formed in the porous layer, and the homogeneous outer layer, the porous layer and the homogeneous inner layer form an A interlayer structure to realize broadband wave transmission. The preparation method provided by the invention adopts an ultraviolet curing 3D printing method for integral preparation, and obtains the antenna housing structure meeting different wave-transmitting requirements by regulating and controlling the thicknesses of the homogeneous outer layer, the homogeneous inner layer and the porous layer as well as the diameters and the hole intervals of the holes. The high-temperature broadband wave-transmitting ceramic radome structure provided by the invention has the advantages of high temperature resistance, broadband wave transmission, high strength, simple structure, good reliability and the like.
Description
Technical Field
The invention relates to the technical field of design and manufacture of broadband wave-transmitting antenna covers, in particular to a high-temperature-resistant broadband wave-transmitting ceramic antenna cover structure and a preparation method thereof.
Background
The antenna housing belongs to a multifunctional wave-transparent structure and is used for protecting a guidance system and the like so that the guidance system can still normally work in a severe thermal environment. With the continuous improvement of the requirements of a guidance system on the aspects of composite guidance, interference resistance, multi-target dealing and the like, the development of the high-temperature resistant broadband wave-transparent antenna housing becomes one of the hot spots of domestic and foreign researches.
The broadband wave-transmitting radome can adopt structural forms such as thin walls, interlayers and metamaterial, the wall thickness of the thin-wall radome needs 1/20 medium wavelengths, the wall thickness is small, the application is less, the interlayer structure adopted at present is a main design method for realizing the broadband wave-transmitting of the radome, and especially in the field of organic composite material radomes, the structural forms such as an interlayer A and an interlayer C are widely adopted for realizing the broadband wave-transmitting. Patent CN103647144A "wide band honeycomb sandwich glass fiber reinforced plastic radome" introduces a preparation method of honeycomb sandwich radome, and paper "ultra wide band radome covering from X band to Ka band" introduces a C sandwich radome structure using quartz fiber/epoxy composite material as skin and PMI foam as core layer.
In the field of ceramic material antenna covers, due to the limitation of a forming process, the difficulty of realizing a sandwich structure is high, and the preparation of the sandwich antenna cover is mainly realized by adopting modes such as bonding, hollow fiber and the like. Patent CN102969566A symmetrical multi-layer multi-band radome structure and preparation method and patent CN102916251A high-temperature wide-band gradient porous silicon nitride radome structure both introduce a method for realizing wide-band wave transmission by adopting a multilayer radome structure formed by compact ceramics and porous layers, but all the layers are connected by adopting a bonding agent, the existence of the bonding agent can bring adverse effects on wave transmission under the high-frequency condition of the radome, and the bonding agent has limited temperature resistance and is easy to lose efficacy at high temperature. Patent CN104446584B "forming method of variable density broadband wave-transparent quartz composite ceramic radome body" and patent CN106129615B "cover body of broadband wave-transparent double-layer composite ceramic radome and preparation method thereof" introduce a quartz ceramic-based radome structure which adopts quartz fibers as outer layer material and hollow quartz fibers as inner layer material to realize double-layer variable density, the preparation process of the method is complicated and is limited by the aperture of the hollow fibers, and the dielectric constant of the inner layer material is difficult to be very low; the manufacture of the ceramic radome with the sandwich structure can also be realized by adopting a multiple-time molding sintering or dipping method, and a paper 'preparation of a sandwich quartz ceramic material' introduces a method for the sandwich quartz ceramic radome with the sandwich structure A, wherein two-time molding is needed, a porous layer is formed by phenolic granulation and sintering, and then the sandwich structure is formed by vacuum dipping, and the molding process is still complex.
The broadband wave-transmitting radome designed by adopting a metamaterial principle is introduced in patent CN10279069A X-waveband ultra-wide wave-transmitting radome, the method is mainly applied to a plane structure, the realization difficulty of preparing the variable-curvature conical radome by adopting the metamaterial is high, and the application is less at present.
Disclosure of Invention
In order to solve the problems in the prior art, the invention provides a high-temperature-resistant broadband wave-transparent ceramic radome structure and a preparation method thereof.
The high-temperature-resistant broadband wave-transparent ceramic radome structure provided by the invention comprises a homogeneous outer layer, a porous layer, a homogeneous inner layer and a homogeneous connecting layer; the porous layer is positioned between the homogeneous outer layer and the homogeneous inner layer, and uniformly distributed holes are formed in the porous layer; and the two ends of the homogeneous outer layer, the porous layer and the homogeneous inner layer are fused and connected with the homogeneous connecting layer, so that an integrated structure is formed.
Optionally, in the high-temperature-resistant broadband wave-transmitting ceramic radome structure, the homogeneous outer layer, the porous layer and the homogeneous inner layer form an a sandwich structure to realize broadband wave transmission.
Optionally, the high-temperature-resistant broadband wave-transparent ceramic radome structure is made of a single wave-transparent ceramic material, and the ceramic material is quartz ceramic or silicon nitride ceramic.
Optionally, the dielectric constant of the homogeneous outer layer, the homogeneous inner layer and the homogeneous connecting layer is 2.5-5, and the overall dielectric constant of the porous layer is 1.6-2.5.
Optionally, the thickness of the homogeneous outer layer and the homogeneous inner layer is 0.5mm to 3mm, the thickness of the porous layer is 3mm to 15mm, and the thickness of the homogeneous connecting layer is 5mm to 15 mm.
Optionally, the diameter of the pores in the porous layer is 0.3mm to 1.5mm, the distance between the pores is 1.2 to 2 times of the diameter of the pores, and the volume percentage of the pores in the porous layer is 10% to 55%.
The invention also provides a preparation method of the high-temperature-resistant broadband wave-transparent ceramic radome structure, which comprises the following steps of:
step 1, measuring the shrinkage rate of a sintered 3D printed ceramic material test piece, and amplifying an antenna housing model according to the measured shrinkage rate to form a printing model;
and 4, degreasing and sintering the ceramic blank to obtain the high-temperature-resistant broadband wave-transmitting radome.
Optionally, the sintering temperature in step 4 is 1200-1600 ℃.
Optionally, the high-temperature-resistant broadband wave-transparent ceramic radome structure is integrally prepared by adopting an ultraviolet curing 3D printing method.
Optionally, the preparation method can obtain the radome structure meeting different wave-transmitting requirements by regulating the thicknesses of the homogeneous outer layer, the homogeneous inner layer and the porous layer and the diameters and hole intervals of the holes.
Compared with the prior art, the high-temperature-resistant broadband wave-transparent ceramic radome structure and the preparation method thereof provided by the invention have the following advantages:
1. the high-temperature-resistant broadband wave-transparent radome structure provided by the invention is integrally prepared by adopting the same material, the formed structure has high strength and small internal stress, the connection is not required to be carried out by using an adhesive, and the reliability is good;
2. the preparation method of the high-temperature-resistant broadband wave-transmitting radome structure provided by the invention can obtain different broadband performances by regulating and controlling the thicknesses, the pore sizes and the pore intervals of the homogeneous outer layer, the homogeneous inner layer and the porous layer, and can meet the application requirements of different occasions.
3. The ultraviolet curing 3D printing method is adopted, the integrated preparation is adopted, the preparation precision is high, and the printed antenna housing can meet the use requirement without continuous secondary processing.
Drawings
Fig. 1 is a schematic structural diagram of a high-temperature-resistant broadband wave-transparent ceramic radome according to the present invention;
fig. 2 is a simulation diagram of the wave-transmitting performance of the high-temperature-resistant broadband wave-transmitting ceramic radome structure.
Detailed Description
The present invention will be further described by the detailed description of preferred embodiments with reference to the accompanying drawings.
As shown in fig. 1, the high-temperature-resistant broadband wave-transparent ceramic radome structure provided by the invention is divided into four parts: a homogeneous outer layer 1, a porous layer 2, a homogeneous inner layer 3 and a homogeneous tie layer 4. The porous layer 2 is positioned between the homogeneous outer layer 1 and the homogeneous inner layer 3, and both ends of the homogeneous outer layer 1, the porous layer 2 and the homogeneous inner layer 3 are fused and connected with the homogeneous connecting layer 4, so that an integrated structure is formed.
The high-temperature-resistant broadband wave-transmitting ceramic radome structure provided by the invention adopts a single wave-transmitting ceramic material, the ceramic material can be quartz ceramic or silicon nitride ceramic, and broadband wave transmission is realized by adopting an A interlayer structure form.
In this embodiment, porous silicon nitride ceramic material is all adopted in four parts of high temperature resistant wide band wave-transparent ceramic radome structure, and the dielectric constant is 3 +/-0.05, and dielectric loss is 0.007, high temperature resistant wide band wave-transparent ceramic radome structure overall length is 400mm, and the bottom diameter is 200 mm. Wherein, the thickness of the homogeneous outer layer 1 and the homogeneous inner layer 3 is both 2mm plus or minus 0.05mm, and the thickness of the porous layer 2 is 5.6mm plus or minus 0.2 mm; the diameter of the pores is 0.5mm, the distance between the pores is 0.7mm, and the volume of the pores in the porous layer 2 accounts for about 40%; the overall dielectric constant of the porous layer 2 is 1.8 +/-0.1, and the homogeneous outer layer 1, the porous layer 2 and the homogeneous inner layer 3 form a sandwich structure so as to meet the requirement of broadband wave transmission.
The homogeneous connecting layer 4 is of a variable thickness structure, the thickness is 8 mm-9.6 mm, the length is 80mm, the homogeneous connecting layer 4 is used for realizing the connection between the antenna housing and the connecting ring, the inner surface is a conical surface, and the taper is 1: 8.
Fig. 2 shows the simulated wave-transmitting rate of the high-temperature-resistant broadband wave-transmitting ceramic radome structure under the condition of C, Ka two wave bands, and it can be seen from the graph that the wave-transmitting rates of the radome of the invention under the two wave bands are all greater than 80%, which indicates that the radome of the invention has good broadband wave-transmitting performance.
The high-temperature-resistant broadband wave-transparent ceramic radome structure is integrally prepared by adopting an ultraviolet curing 3D printing method, and the preparation method comprises the following steps:
firstly, the shrinkage rate of a 3D printing ceramic material test piece after sintering is measured. Adopting ultraviolet light to solidify the 3D printing test piece, measuring the dimension l along the height or diameter direction1And measuring in the same direction after sintering to obtain test result l2When the shrinkage rate is
The shrinkage rate is generally 20-30%, and the antenna housing model is enlarged according to the measured shrinkage rate to form a printing model. The sintered test piece is a scaled sample piece or a flat plate type component of the antenna housing.
Secondly, the slurry is prepared by uniformly mixing photocuring resin, silicon nitride ceramic powder, a dispersing agent, a photoinitiator and the like according to a certain volume ratio, wherein the volume proportion of the photocuring resin can be 30-50%, the volume proportion of the ceramic powder can be 50-70%, the volume proportion of the dispersing agent can be 0.5-2%, and the volume proportion of the photoinitiator can be 0.5-2%. In this example, the particle size of the silicon nitride ceramic powder was 50 nm.
And thirdly, forming a complete ceramic blank body on the ceramic photocuring 3D printing equipment through layer-by-layer superposition according to the printing model, wherein the thickness of each layer is 0.1 mm. The 3D printing can be according to the product of the shape of design manufacture arbitrary shape, and the aperture of the antenna house structure porous layer that this embodiment provided is 0.3mm ~ 1.5mm, and the hole interval is 0.5mm ~ 1.5mm, through changing the quantity and the interval of hole, can adjust the volume ratio of hole in the porous layer, makes the volume ratio of hole between 10% ~ 55% to change the dielectric constant of prefabricated hole layer, form the sandwich structure of different wave transmittances.
And finally, degreasing and sintering the ceramic blank to obtain the high-temperature-resistant broadband wave-transmitting radome with the required specification, wherein the sintering temperature of the ceramic blank is 1350-1400 ℃.
According to the preparation method of the high-temperature-resistant broadband wave-transmitting ceramic radome structure, the thickness of the homogeneous outer layer 1, the homogeneous inner layer 3 and the porous layer 2, the diameter of the holes and the hole spacing can be regulated and controlled, and the radome structure meeting different wave-transmitting requirements can be obtained.
According to the high-temperature-resistant broadband wave-transmitting ceramic radome structure, the holes which are uniformly distributed are formed in the porous layer, and the A interlayer structure is formed by the homogeneous outer layer, the porous layer and the homogeneous inner layer so as to realize broadband wave transmission; the antenna housing structure is integrally molded and prepared by adopting an ultraviolet curing 3D printing method, and has the advantages of high temperature resistance, wide frequency wave transmission, high strength, simple structure, good reliability and the like.
While the present invention has been described in detail with reference to the preferred embodiments, it should be understood that the above description should not be taken as limiting the invention. Various modifications and alterations to this invention will become apparent to those skilled in the art upon reading the foregoing description. Accordingly, the scope of the invention should be determined from the following claims.
Claims (10)
1. A high-temperature-resistant broadband wave-transparent ceramic radome structure is characterized by comprising a homogeneous outer layer, a porous layer, a homogeneous inner layer and a homogeneous connecting layer;
the porous layer is positioned between the homogeneous outer layer and the homogeneous inner layer, and uniformly distributed holes are formed in the porous layer; and the two ends of the homogeneous outer layer, the porous layer and the homogeneous inner layer are fused and connected with the homogeneous connecting layer, so that an integrated structure is formed.
2. The radome structure of claim 1, wherein the high-temperature-resistant broadband wave-transparent ceramic radome structure comprises an a-sandwich structure formed by a homogeneous outer layer, a porous layer and a homogeneous inner layer, so as to realize broadband wave-transparent.
3. The radome structure of claim 1, wherein the high-temperature-resistant broadband wave-transparent ceramic radome structure is made of a single wave-transparent ceramic material, and the ceramic material is quartz ceramic or silicon nitride ceramic.
4. The radome structure of claim 1, wherein the dielectric constant of the homogeneous outer layer, the homogeneous inner layer and the homogeneous connection layer is 2.5 to 5, and the overall dielectric constant of the porous layer is 1.6 to 2.5.
5. The radome structure of claim 1, wherein the homogeneous outer layer and the homogeneous inner layer have a thickness of 0.5mm to 3mm, the porous layer has a thickness of 3mm to 15mm, and the homogeneous connection layer has a thickness of 5mm to 15 mm.
6. The radome structure of claim 1, wherein the diameter of the holes in the porous layer is 0.3mm to 1.5mm, the pitch of the holes is 1.2 to 2 times the diameter of the holes, and the volume of the holes in the porous layer is 10% to 55%.
7. A preparation method of the high-temperature-resistant broadband wave-transparent ceramic radome structure based on any one of claims 1-6 is characterized by comprising the following steps:
step 1, measuring the shrinkage rate of a sintered 3D printed ceramic material test piece, and amplifying an antenna housing model according to the measured shrinkage rate to form a printing model;
step 2, preparing slurry by using photo-curing resin, ceramic powder, a dispersing agent and a photoinitiator;
step 3, forming a complete ceramic blank body on ceramic photocuring 3D printing equipment by layer-by-layer superposition according to a printing model, wherein the thickness of each layer is 0.05-0.2 mm;
and 4, degreasing and sintering the ceramic blank to obtain the high-temperature-resistant broadband wave-transmitting radome.
8. The method for manufacturing the radome of claim 7, wherein the sintering temperature in the step 4 is 1200 ℃ to 1600 ℃. .
9. The manufacturing method of the radome of claim 7, wherein the high-temperature-resistant broadband wave-transparent ceramic radome structure is integrally manufactured by an ultraviolet curing 3D printing method.
10. The method for manufacturing the radome of claim 7, wherein the method for manufacturing the radome can obtain the radome structure meeting different wave-transmitting requirements by regulating the thicknesses of the homogeneous outer layer, the homogeneous inner layer and the porous layer, and the diameters and the hole intervals of the holes.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010187521.8A CN111244628A (en) | 2020-03-17 | 2020-03-17 | High-temperature-resistant broadband wave-transparent ceramic radome structure and preparation method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010187521.8A CN111244628A (en) | 2020-03-17 | 2020-03-17 | High-temperature-resistant broadband wave-transparent ceramic radome structure and preparation method thereof |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN111244628A true CN111244628A (en) | 2020-06-05 |
Family
ID=70866082
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010187521.8A Pending CN111244628A (en) | 2020-03-17 | 2020-03-17 | High-temperature-resistant broadband wave-transparent ceramic radome structure and preparation method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111244628A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112510359A (en) * | 2020-11-20 | 2021-03-16 | 湖北航天技术研究院总体设计所 | Invisible antenna housing |
| CN114014671A (en) * | 2021-11-11 | 2022-02-08 | 西安国宏天易智能科技有限公司 | Preparation method of silicon nitride-based ceramic radome |
-
2020
- 2020-03-17 CN CN202010187521.8A patent/CN111244628A/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112510359A (en) * | 2020-11-20 | 2021-03-16 | 湖北航天技术研究院总体设计所 | Invisible antenna housing |
| CN114014671A (en) * | 2021-11-11 | 2022-02-08 | 西安国宏天易智能科技有限公司 | Preparation method of silicon nitride-based ceramic radome |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN110829018B (en) | Broadband wide-angle frequency selective surface radome | |
| CN111244628A (en) | High-temperature-resistant broadband wave-transparent ceramic radome structure and preparation method thereof | |
| CN107188596B (en) | Porous gradient silicon nitride-silicon carbide composite ceramic and preparation method and application thereof | |
| EP1838141B1 (en) | Laminated body and method for producing the same | |
| CN102211938B (en) | Microwave absorbing ceramic of silicon carbide compound material and preparation method thereof | |
| EP3617269B1 (en) | Epoxy resin wave-absorbing composite material and preparation method thereof | |
| EP1359133A1 (en) | Porous ceramic and method for preparation thereof, and microstrip substrate | |
| US8282763B2 (en) | Magnetic-dielectric assemblies and methods of fabrication | |
| WO2014005514A1 (en) | Metamaterial and manufacturing method threfor | |
| US6091375A (en) | Radome | |
| US20020132136A1 (en) | Low loss, high frequency composite magnetic material and methods of making the same | |
| CN102303441B (en) | Wave-transmitting material with broadband resin matrix interlayer structure and preparation method of wave-transmitting material | |
| JP2011211521A (en) | Flying object radome | |
| CN111016231A (en) | PTFE ceramic film for 5G network high-performance copper-clad plate and processing method thereof | |
| KR101771741B1 (en) | Filter chip elements and method for preparing thereof | |
| CN107216153A (en) | A kind of 3D printing method of ceramic material | |
| CN107473725B (en) | Preparation method of nested matrix | |
| CN113683425B (en) | Photocuring silicon nitride ceramic and preparation method thereof with gradient structure | |
| Miek et al. | Ceramic additive manufactured monolithic X-shaped TM dual-mode filter | |
| JP3995342B2 (en) | Ferrite toroid manufacturing method | |
| CN113788472B (en) | 3D printing forming method of three-dimensional graphene composite material | |
| CN106299715B (en) | Metamaterial and preparation method thereof | |
| CN114436671B (en) | Foam ceramic-based interference type wave-absorbing material and preparation method thereof | |
| She et al. | Variable dielectric constants by structured porosity for passive ceramic components | |
| Skaik et al. | 3D printed microwave components for frequencies above 100 GHz |
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 | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20200605 |
|
| RJ01 | Rejection of invention patent application after publication |