Manufacturing process of dual-band structure integrated antenna unit

Abstract

The invention discloses a manufacturing process of an integrated antenna unit with a dual-band structure, which relates to the technical field of antenna manufacturing and comprises the following steps of: processing a metal core; preheating the metal core; mold closing injection molding is carried out, and plastic wraps the metal core to be tightly combined; carrying out corrosion-resistant surface treatment on the metal core which is not encapsulated by the plastic; electroplating a metal pattern; packaging the electroplated metal pattern by using the same plastic; and assembling a metal connector on the encapsulated workpiece and welding to obtain the dual-band structure integrated antenna unit. The metal core and the plastic layer are integrated and do not need to be assembled, and the metal patterns of the two frequency bands are formed at a time through electroplating. The metal core is wrapped in the plastic layer, the bonding strength is high, the sealing effect is good, only one plastic medium is arranged between the metal pattern and the metal core, and the dielectric constant is stable.

Description

Technical Field

[0001] This invention patent relates to the field of antenna manufacturing technology, and in particular to a manufacturing process for an integrated dual-band antenna unit. Background Technology

[0002] As a key component of radar, the performance of the antenna directly affects the radar's detection capability. Currently, antenna elements on the radar antenna array can only transmit and receive signals in a single frequency band, limiting their ability to detect and identify objects within a specific range or of a specific type.

[0003] Dual-band co-aperture antenna arrays can integrate high- and low-frequency antenna arrays into a single aperture within a limited aperture, improving the system's aperture utilization. By integrating low-frequency and high-frequency antennas, it can simultaneously perform airspace scanning and target illumination tasks, enabling the detection of both mid- and high-altitude targets and low-altitude targets, and facilitating both wide-area target surveys and detailed local target surveys.

[0004] In various forms of dual-frequency common-aperture antennas, the high-frequency and low-frequency antennas are typically arranged independently and periodically within the array. This causes periodic variations in the aperture field of the high-frequency antenna, leading to quantization lobe effects and a significant deterioration in its sidelobe level.

[0005] To address the above issues, a dual-band integrated unit was developed, achieving a 1:1 common aperture arrangement for high and low frequencies. This not only maximizes space utilization but also eliminates the periodic variations introduced by the low-frequency antenna because both high and low frequency antennas share the same radiating structure. Traditional manufacturing methods primarily involve CNC split machining followed by assembly, resulting in significant material waste, long production cycles, and high costs. Furthermore, gaps exist between assembled parts, making it difficult to meet the requirements for outdoor use. Summary of the Invention

[0006] To address the aforementioned technical problems, this invention provides a manufacturing process for an integrated dual-band antenna unit, comprising the following steps: A manufacturing process for an integrated dual-band antenna unit includes the following steps: 1) Metal core processing and forming; 2) After the metal core is preheated, it is placed into the injection mold for positioning; 3) Injection molding with mold closing to tightly bond the plastic to the metal core; 4) Apply corrosion-resistant surface treatment to metal cores that have not been encapsulated in plastic; 5) Metal graphic fabrication: Electroplating metal graphics onto the surface of the plastic wrapping layer. 6) Use the same type of plastic to encapsulate the electroplated metal pattern; 7) Assemble the metal connector onto the encapsulated workpiece and weld it to the tin-plated pattern to obtain a dual-band integrated antenna unit.

[0007] Furthermore, step 5) specifically involves: plating the injection molded part with nickel; carving the required dual-band circuit pattern on the surface of the nickel layer and removing the excess nickel layer outside the pattern; electroplating the workpiece with copper; after copper plating, electroplating the workpiece with tin; and performing tin protection after tin plating.

[0008] Furthermore, the metal core material is selected from aluminum alloy, stainless steel, and titanium alloy.

[0009] Furthermore, the metal core is formed by CNC machining, die casting, or powder metallurgy.

[0010] Furthermore, the plastic used for injection molding is selected from PEI, PPO, PPS, PE, and PP.

[0011] Furthermore, the encapsulation is carried out by laser welding, ultrasonic welding, or adhesive bonding.

[0012] Furthermore, the metal core is preheated at 150℃-180℃ for 2 hours.

[0013] Furthermore, the plastic surface is treated with laser equipment or sandblasting equipment before nickel plating.

[0014] Furthermore, the nickel plating thickness is controlled to be less than 1 μm, the copper plating thickness is ≥8 μm, and the tin plating thickness is ≥8 μm.

[0015] Furthermore, an electroplated protective layer is added to the required areas on the surface of the metal core before nickel plating, and the protective layer is removed after tin plating.

[0016] Compared with the prior art, the present invention has the following beneficial effects: (1) By using integrated injection molding and electroplating, the metal core and plastic layer are integrated, without the need to process the plastic layer with a complex shape according to the shape of the metal core before assembly and connection, saving raw materials, and reducing raw material costs and processing costs.

[0017] (2) The metal patterns of the two frequency bands can be formed in one electroplating, which shortens the product processing cycle, simplifies the manufacturing process, and reduces the manufacturing difficulty.

[0018] (3) The metal core is wrapped inside the plastic layer by injection molding and formed in one step. There is only one material, plastic, between the metal pattern and the metal core. The dielectric constant is stable. The thickness of the plastic layer is guaranteed by the mold, resulting in high thickness consistency and stable electrical performance.

[0019] (4) The metal core is wrapped inside the plastic layer by injection molding. The metal core and the plastic layer have high bonding strength and good sealing effect. The metal pattern is sealed and protected by the cover plate, and has strong environmental adaptability. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of an integrated antenna unit with a dual-band structure; Figure 2 This is a flowchart of the manufacturing process for a dual-band integrated antenna unit.

[0021] Among them, 1 is the metal core, 2 is the plastic layer, 3 is the plastic encapsulation, 4 is the connector, and 5 is the electroplated pattern. Detailed Implementation

[0022] The technical solution of the present invention will be further explained below with reference to the accompanying drawings. Example 1

[0023] A manufacturing process for an integrated dual-band structure unit includes the following steps: 1) Metal core processing: The metal core is processed according to the attached... Figure 1 The metal core structure is made of aluminum alloy CNC machined and deburred after machining. 2) Preheating of the metal core: Before injection molding, preheat the metal core to 150℃ for 2 hours; 3) Place the metal core into the injection mold and position it using the positioning device inside the injection mold; 4) Mold closing and injection molding: After the injection mold is closed, PEEK is heated to 375±5℃ and melted, then poured into the injection molding machine's melting cup. It is then injected into the mold through the injection machine with an injection force of 130MPa. The PEEK solution encapsulates the metal core. 5) Mold opening and part removal: After the injection is completed and under the action of pressure, the plastic and metal core are tightly bonded together. After holding the casting pressure for 10s to 15s, the mold is opened and the injection molded part is removed. 6) Remove gates and burrs; 7) Metal surface treatment: Conductive oxidation treatment is performed on the metal core that has not been encapsulated in plastic to improve the surface corrosion resistance; 8) Metal protection: The surface of the metal core that has not been encapsulated in plastic is protected with RH-150 peelable blue adhesive and cured in a cabinet oven at 150℃ for 25 minutes. 9) Roughening: Use laser equipment or sandblasting equipment to treat the plastic surface to improve surface cleanliness and roughness; 10) Electroless nickel plating: The injection molded parts after protection and roughening treatment are immersed in a chemical solution to deposit nickel ions on the surface of the workpiece. The electroless nickel layer is uniform and the thickness is controlled to be less than 1 μm. 11) Laser engraving: Using positioning fixtures and laser equipment, the desired electrical circuit outline pattern is precisely laser engraved on the surface of the chemical nickel layer, and the excess nickel layer outside the pattern is removed. 12) Copper electroplating: The workpiece is re-hung, degreased, washed with water, activated, and then electroplated in a copper sulfate solution to obtain the required copper layer with a thickness ≥8um. The copper layer grows on the nickel layer to obtain a precise copper layer.

[0024] 13) Electroplating tin: The workpiece is re-hung, degreased, washed with water, activated, and then the tin layer is replaced in stannous sulfate solution with a thickness ≥8μm. The tin layer is uniformly covered on the copper layer. 14) Post-treatment: After tin plating, tin protection is applied, followed by drying and hanging. 15) Remove metal protection: Remove the peelable adhesive from the surface of the metal core; 16) Surface encapsulation: The PEEK cover plate is welded to the surface of the injection molded part by laser welding to protect the electroplated metal pattern; 17) Connector soldering: The metal connector is assembled onto the encapsulated workpiece and soldered to the pattern layer. The presence of the tin layer provides a basis for soldering. After soldering, the solder joints are coated with silicone for protection, resulting in a dual-band integrated antenna unit. Example 2

[0025] A manufacturing process for an integrated dual-band structure unit includes the following steps: 1) Metal core processing: The metal core is processed according to the attached... Figure 1 The metal core structure is made of aluminum alloy CNC machined and deburred after machining. 2) Preheating of the metal core: Before injection molding, preheat the metal core to 180℃ for 2 hours; 3) Place the metal core into the injection mold and position it using the positioning device inside the injection mold; 4) Mold closing and injection molding: After the injection mold is closed, PEEK is heated to 375±5℃ and melted, then poured into the injection molding machine's melting cup. It is then injected into the mold through the injection machine with an injection force of 130MPa. The PEEK solution encapsulates the metal core. 5) Mold opening and part removal: After the injection is completed and under the action of pressure, the plastic and metal core are tightly bonded together. After holding the casting pressure for 10s to 15s, the mold is opened and the injection molded part is removed. 6) Remove gates and burrs; 7) Metal surface treatment: Conductive oxidation treatment is performed on the metal core that has not been encapsulated in plastic to improve the surface corrosion resistance; 8) Metal protection: The surface of the metal core that has not been encapsulated in plastic is protected with RH-150 peelable blue adhesive and cured in a cabinet oven at 150℃ for 25 minutes. 9) Roughening: Use laser equipment or sandblasting equipment to treat the plastic surface to improve surface cleanliness and roughness; 10) Electroless nickel plating: The injection molded parts after protection and roughening treatment are immersed in a chemical solution to deposit nickel ions on the surface of the workpiece. The electroless nickel layer is uniform and the thickness is controlled to be less than 1 μm. 11) Laser engraving: Using positioning fixtures and laser equipment, the required electrical circuit outline pattern is precisely laser engraved on the surface of the chemical nickel layer to form the dividing line; 12) Copper electroplating: The workpiece is re-hung, degreased, washed with water, activated, and then electroplated in copper sulfate solution to obtain the required copper layer with a thickness ≥8um; 13) Electroplating tin: The workpiece is re-hung, degreased, washed with water, activated, and then the tin layer is replaced in stannous sulfate solution with a thickness ≥8μm; 14) Post-treatment: After tin plating, tin protection is applied, followed by drying and hanging. 15) Remove metal protection: Remove the peelable adhesive from the surface of the metal core; 16) Surface encapsulation: The PEEK cover plate is bonded to the injection molded part with an adhesive film. The adhesive film material is PES, the film thickness is 0.1mm, the baking temperature is 110℃, and the baking time is 1 hour to protect the electroplated metal pattern. 17) Connector welding: Assemble the metal connector onto the encapsulated workpiece and weld it. After welding, apply silicone to the solder joint for protection to obtain a dual-band integrated antenna unit.

Claims

1. A manufacturing process for an integrated dual-band antenna unit, characterized in that: Includes the following steps: 1) Metal core processing and forming; 2) After the metal core is preheated, it is placed into the injection mold for positioning; 3) Injection molding with mold closing to tightly bond the plastic to the metal core; 4) Apply corrosion-resistant surface treatment to metal cores that have not been encapsulated in plastic; 5) Metal graphic fabrication: Electroplating metal graphics onto the surface of the plastic wrapping layer. 6) Use the same type of plastic to encapsulate the electroplated metal pattern; 7) Assemble the metal connector onto the encapsulated workpiece and weld it to the tin-plated pattern to obtain a dual-band integrated antenna unit.

2. The manufacturing process of the integrated dual-band antenna unit according to claim 1, characterized in that: Step 5) specifically involves: plating the injection molded part with nickel; carving the required dual-band circuit pattern on the surface of the nickel layer and removing the excess nickel layer outside the pattern; electroplating the workpiece with copper; and after copper plating, electroplating the workpiece with tin. Tin plating is followed by tin protection.

3. The manufacturing process of the integrated dual-band antenna unit according to claim 1, characterized in that: The metal core material is selected from aluminum alloy, stainless steel, and titanium alloy.

4. The manufacturing process of the integrated dual-band antenna unit according to claim 1, characterized in that: The metal core is formed by CNC machining, die casting, or powder metallurgy.

5. The manufacturing process of the integrated dual-band antenna unit according to claim 1, characterized in that: The plastic used for injection molding is selected from PEI, PPO, PPS, PE, and PP.

6. The manufacturing process of the integrated dual-band antenna unit according to claim 1, characterized in that: The encapsulation is performed by laser welding, ultrasonic welding, or adhesive bonding.

7. The manufacturing process of the integrated dual-band antenna unit according to claim 1, characterized in that: The metal core is preheated to 150℃-180℃ for 2 hours.

8. The manufacturing process of the integrated dual-band antenna unit according to claim 2, characterized in that: Before nickel plating, the plastic surface is treated with laser equipment or sandblasting equipment.

9. The manufacturing process of the integrated dual-band antenna unit according to claim 2, characterized in that: The nickel plating thickness is controlled to be less than 1 μm, the copper plating thickness is ≥8 μm, and the tin plating thickness is ≥8 μm.

10. The manufacturing process of the integrated dual-band antenna unit according to claim 2, characterized in that: Before nickel plating, an electroplating protective layer is added to the required areas on the surface of the metal core, and the protective layer is removed after tin plating.

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