Magnetic bead based on nickel-zinc ferrite material and manufacturing process thereof

Abstract

The invention relates to the technical field of magnetic beads, and particularly discloses a magnetic bead based on a nickel-zinc ferrite material and a manufacturing process of the magnetic bead based on the nickel-zinc ferrite material. The side, close to the first magnetic structure layer, of the second magnetic structure layer, the side, close to the first magnetic structure layer, of the third magnetic structure layer and the side, close to the first magnetic structure layer, of the fourth magnetic structure layer are each provided with an internal conductor layer. Dielectric layers are arranged on one side, close to the first magnetic structure layer, of the second magnetic structure layer and one side, close to the first magnetic structure layer, of the fourth magnetic structure layer; at least one part of the inner conductor layer surrounds the dielectric layer, the height difference between the dielectric layer and the inner conductor layer can form a gap in the magnetic bead, and the gap is used for interrupting a magnetic path, so that enough high impedance can be presented during large current, and large-current noise current can be effectively prevented or attenuated.

Description

Technical Field

[0001] The invention relates to the technical field of magnetic beads, and in particular discloses a magnetic bead based on nickel-zinc ferrite material and a manufacturing process thereof. Background Art

[0002] With the rapid development of modern electronic technology, magnetic beads are increasingly used in various electronic devices. However, traditional magnetic beads have many limitations in material selection, structural design, and processing technology, which makes it difficult for their performance to meet the requirements of modern electronic devices for high current, high integration, and high reliability.

[0003] Traditional magnetic beads mostly use ferrite or iron powder as magnetic materials. These materials are prone to magnetic saturation and large magnetic loss in high current environments, resulting in reduced performance of the magnetic beads. In addition, the structural design of traditional magnetic beads is relatively simple, and it is difficult to achieve a multi-layer structure, which limits the impedance maintenance ability of the magnetic beads under large DC bias. At the same time, the accuracy and efficiency of traditional processing technology are also low, which is difficult to meet the requirements of modern electronic devices for high performance and high integration of magnetic beads. Summary of the invention

[0004] In order to overcome the shortcomings and deficiencies in the prior art, the object of the present invention is to provide a magnetic bead based on nickel-zinc ferrite material and a manufacturing process thereof.

[0005] To achieve the above-mentioned purpose, a magnetic bead based on nickel-zinc ferrite material of the present invention comprises a plurality of magnetic structural layers stacked together, wherein the magnetic structural layer has four layers, an internal conductor layer is arranged on one side of the second magnetic structural layer close to the first magnetic structural layer, a side of the third magnetic structural layer close to the first magnetic structural layer, and a side of the fourth magnetic structural layer close to the first magnetic structural layer, and a dielectric layer is arranged on one side of the second magnetic structural layer close to the first magnetic structural layer and a side of the fourth magnetic structural layer close to the first magnetic structural layer; at least a part of the internal conductor layer is surrounded by a dielectric layer, the thickness of the internal conductor layer is greater than the thickness of the dielectric layer, the free end of the internal conductor layer protrudes out of the free end of the dielectric layer, and the height difference between the dielectric layer and the internal conductor layer can form a gap in the magnetic bead, and the gap is used to interrupt the magnetic path so that a sufficiently high impedance can be presented when a large current is flowing, so as to effectively prevent or attenuate the passage of large current noise, and convert the large current noise into heat energy consumed inside the magnetic bead; Limiting protrusions are arranged on one side of the second magnetic structure layer close to the first magnetic structure layer, on one side of the third magnetic structure layer close to the first magnetic structure layer, and on one side of the fourth magnetic structure layer close to the first magnetic structure layer; limiting grooves used in conjunction with the limiting protrusions are arranged on one side of the first magnetic structure layer close to the fourth magnetic structure layer, on one side of the second magnetic structure layer close to the fourth magnetic structure layer, and on one side of the third magnetic structure layer close to the fourth magnetic structure layer; the magnetic structure layers are laminated into a laminated structure by pressing the limiting protrusions and the limiting grooves, and the laminated structure is an integrated magnetic bead product.

[0006] As the material of the magnetic structure layer, nickel-zinc ferrite has the characteristics of low coercivity, high magnetic permeability and high operating frequency band, which enables the magnetic beads to maintain excellent performance in a high current environment. Compared with traditional high current current sensor core materials (such as Permalloy, amorphous alloy and manganese-zinc ferrite, etc.), nickel-zinc ferrite can support higher operating frequencies and meet the needs of modern electronic devices for magnetic beads.

[0007] By adopting multiple magnetic structural layers and specific internal conductor layers and dielectric layer configurations, magnetic beads can show better performance under high current. This design helps to reduce energy loss under high current and improve the efficiency of magnetic beads. Inside the magnetic bead, the dielectric layer is surrounded by the internal conductor layer and a gap is formed, interrupting the magnetic path. This design enables the magnetic beads to maintain a high magnetic bead value or impedance when subjected to a large DC bias, thereby ensuring that the magnetic beads can maintain stable performance under a wide range of working conditions. By providing limiting protrusions and limiting grooves on each magnetic structural layer, the layers can be tightly pressed together to form a laminated structure. This design not only improves the structural strength of the magnetic beads, but also ensures precise alignment and close contact between the layers, thereby improving the reliability and durability of the magnetic beads. By adopting a standardized limiting protrusion and limiting groove design, the manufacturing and assembly process of the magnetic beads can be simplified. This design makes the alignment and fixation between the layers easier and more precise, reducing manufacturing costs and improving production efficiency.

[0008] The magnetic structure layer is nickel-zinc ferrite, and the thickness of the magnetic structure layer is 50-300um. The thickness of the magnetic structure layer is precisely controlled within the range of 50-300 microns (um), and this design helps to optimize the performance of the magnetic beads. The appropriate thickness not only helps to ensure that the magnetic beads have sufficient magnetic bead quantity and impedance, but also maintains its structural stability and reliability.

[0009] The internal conductor layer is a silver paste layer, and the thickness of the internal conductor layer is 200um. Silver, as a metal with excellent conductivity, makes the internal conductor layer have excellent conductivity. The silver paste material has good processability and is easy to be evenly coated on the magnetic structure layer through processes such as screen printing. While maintaining high performance, the 200-micron thickness design also optimizes the space utilization of the magnetic beads, which helps to improve the overall performance and reliability of the device.

[0010] The dielectric layer is a dielectric ceramic layer, and the thickness of the dielectric layer is 5-50um. The dielectric layer is made of dielectric ceramic material, which has a high dielectric constant and stable physical and chemical properties; the high dielectric constant helps to enhance the capacitance effect of the magnetic beads, thereby maintaining stable magnetic bead performance and impedance characteristics in a large current environment. At the same time, dielectric ceramics, as an excellent insulating material, can ensure that the dielectric layer has good insulation properties in a large current environment; a dielectric layer of appropriate thickness not only helps to maintain the insulation properties of the dielectric layer, but also ensures that the gap between it and the internal conductor layer is large enough to interrupt the magnetic path and maintain high magnetic beads or impedance.

[0011] The magnetic bead also includes a first connector arranged on the side of the second magnetic structural layer close to the first magnetic structural layer, and a second connector is arranged on the side of the fourth magnetic structural layer close to the third magnetic structural layer. A conductive channel is arranged between the first connector and the second connector. The conductive channel is opened on the magnetic structural layer and is used to fill the conductive material. The first connector is used to connect the internal conductor layer on the second magnetic structural layer and the internal conductor layer on the third magnetic structural layer; the second connector is used to connect the internal conductor layer on the third magnetic structural layer and the internal conductor layer on the fourth magnetic structural layer.

[0012] The first connector and the second connector are used to conduct the internal conductor layers on different magnetic structure layers, thereby realizing the electrical connection between the multiple internal conductor layers. By directly opening a conductive channel on the magnetic structure layer and filling it with conductive material, it is possible to avoid the use of additional connecting wires or connectors, which helps to reduce the volume and weight of the magnetic beads and improve their integration and portability.

[0013] The conductive material includes the following substances in parts by weight: 5-7 parts of inorganic powder composed of metal magnetic powder, 3-5 parts of lead-free glass powder, 1-2 parts of organic carrier and 1-2 parts of auxiliary agent; the inorganic powder includes at least one of iron-silicon-aluminum alloy, iron-nickel alloy, iron-silicon alloy, carbonyl iron powder and molybdenum-permalloy; the lead-free glass powder includes the following substances in parts by weight: 1-3 parts of lithium oxide, 1-4 parts of potassium oxide, 15-20 parts of boron trioxide, 15-25 parts of bismuth oxide and 35-50 parts of silicon dioxide; the organic carrier includes the following substances in parts by weight: 10-20 parts of high boiling point solvent and 1-3 parts of binder; the auxiliary agent includes the following substances in parts by weight: 1-3 parts of dispersant, 1-2 parts of plasticizer, 2-3 parts of thixotropic agent and 2-3 parts of coupling agent.

[0014] The through hole shape on the conductive channel is circular, triangular, elliptical or quadrilateral, and the through hole shape is selected according to actual needs.

[0015] A process for manufacturing a magnetic bead based on nickel-zinc ferrite material comprises the following steps: S1. Pretreatment: preparing a magnetic structural layer, mixing nickel-zinc ferrite powder with a bonding additive into a magnetic material slurry, the magnetic material slurry is made into a raw ceramic sheet by a tape casting process, and the raw ceramic sheet is cut into magnetic structural layers of the same size by a laser cutting process; S2. Printing the internal conductor layer: Select silver paste as the material of the internal conductor layer, mix the silver paste with ink solvent in proportion to form a conductive paste with appropriate viscosity and fluidity, use screen printing technology to evenly print the conductive paste on the magnetic structure layer in multiple times, and bake the conductive paste after it is printed to 200um; S3, printing dielectric layer: mixing the prepared dielectric ceramic powder and ink additives to form a printing slurry with appropriate viscosity and fluidity; applying it on the magnetic structure layer with the printed internal conductor layer by screen printing, and drying it to enhance the bonding force between the printed dielectric layer and the magnetic structure layer; S4, stacking: The stacking mechanism precisely positions the multiple magnetic structural layers according to the preset arrangement structure, stacks them, and then puts them into the mold. After stacking, a stacked body is formed. The stacked body is placed in a high-temperature resistant nylon composite film bag, which is vacuumed to -0.1 MPa and then sealed. Deionized water is injected into the rigid mold cavity, and the high-temperature resistant nylon composite film bag with the stacked body placed is immersed in the rigid mold cavity. The hot pressing mechanism heats and pressurizes the water in the rigid mold cavity so that the layers of raw embryos in the stacked body are fused to form a whole. S5, debinding: Put the laminate into the debinding furnace, and decompose and remove the colloidal substances in the green body by slow and uniform heating, so as to reduce the product cracking caused by the violent decomposition and gasification of such substances during the sintering process; S6, sintering: placing the debinding laminate into a sintering furnace, and subjecting the laminate to high-temperature sintering to make it dense; S7, silver end: silver paste is applied to the ends of both sides of the sintered laminate and sintered to form a conductive silver end layer for the convenience of product welding; S8, electroplating: electroplating the silver layer at both ends of the product with tin and nickel to improve the oxidation resistance, wear resistance and solderability of the product ends.

[0016] Between S2 and S3, step S2.1 is also included: Opening a conductive channel: installing the first connector on the free end of the internal conductor layer on the fourth magnetic structure layer, and installing the second connector on the free end of the internal conductor layer on the third magnetic structure layer; using laser cutting to open a conductive channel on the magnetic structure layer and the internal conductor layer, and then filling the conductive material into the opened conductive channel to form an electrical connection; A process for manufacturing magnetic beads based on nickel-zinc ferrite material, wherein S1 further comprises S1.1: The laser cutting system in the laser processing equipment draws the parameters of the raw ceramic piece and forms a cutting code waiting for the cutting operation.

[0017] The S1.1 also includes S1.1.1: (a) loading the raw ceramic sheet onto a processing table via a loading mechanism of a laser processing device, wherein a positioning fixture is provided on the processing table to position the raw ceramic sheet on the processing table and wait for the next step; (b) The laser processing equipment includes a control center and a cutting unit. The control center sets the cutting path, feed rate, and rotation speed of the cutter according to the cutting code formed by the cutting size drawn by the laser cutting system to drive the cutting unit to cut the raw ceramic sheet.

[0018] A process for manufacturing magnetic beads based on nickel-zinc ferrite material, further comprising the following steps: S9. Defect detection: The laminated structure is placed into the detection system. The detection system is equipped with a high-resolution industrial camera to automatically locate and detect the laminated structure. The laminated structure that passes the inspection will be shipped out, and the unqualified laminated structure will be transported to the defective product station for reprocessing.

[0019] The line width of the printed internal conductor layer is in the range of 0.5-1.5 mm, and the line width of the side of the internal conductor layer away from the dielectric layer and the magnetic structure layer is in the range of 0.2-0.6 mm.

[0020] The line width of the internal conductor layer is designed to be within the range of 0.5-1.5mm, which helps to ensure the uniform distribution of current in the conductor layer, reduce the loss and interference of electromagnetic energy, and thus improve the electromagnetic performance of the magnetic beads. At the same time, the line width design of the magnetic structure layer can further optimize the magnetic bead value and quality factor of the magnetic beads to meet the needs of specific application scenarios.

[0021] The S1 pretreatment to prepare the magnetic structure layer also includes the following steps: (a) breaking up the nickel-zinc ferrite by a breaking mechanism and then putting it into a grinder for multiple grinding to form nickel-zinc ferrite powder; (b) The ground nickel-zinc ferrite powder is placed in a screening mechanism for screening and then waits for the next step.

[0022] The grinding machine comprises a base, a grinding motor, a grinding part and a discharge part, wherein the output end of the grinding motor is connected to the grinding part, the grinding part is arranged above the discharge part, and the grinding motor drives the grinding part to rotate to grind the metal magnetic slurry placed in the discharge part; The base is also provided with a sliding guide rail and a sliding guide motor. The grinding part is installed on the base via the sliding guide rail, and the sliding guide motor drives the grinding part to move back and forth up and down along the sliding guide rail. When grinding is in progress, the sliding guide motor drives the grinding part to approach the discharge part, and when grinding is finished, the sliding guide motor drives the grinding part to move upward away from the discharge part.

[0023] The grinding machine also includes a temperature measuring unit and a heating unit. The heating unit is arranged on the discharge part and is used to heat the magnetic slurry placed in the discharge part to prevent the magnetic slurry from agglomerating and ensure the uniformity and stability of the slurry.

[0024] Beneficial effects of the present invention: The magnetic beads of the present invention use nickel-zinc ferrite as the material of the magnetic structure layer. The material has the characteristics of low coercivity, high magnetic permeability and high operating frequency band, and can maintain excellent performance in a large current environment. At the same time, through a multi-layer structure design (four magnetic structure layers), an internal conductor layer and a dielectric layer are arranged on a specific layer to form a gap formed by a height difference to interrupt the magnetic path, thereby maintaining a high magnetic bead or impedance under a large DC bias. In addition, by utilizing the design of the first connector, the second connector and the conductive channel, electrical connection between the multiple internal conductor layers is achieved, thereby improving the integration and portability of the magnetic beads.

[0025] By ensuring precise processing through laser cutting, combined with multi-layer structure design (including magnetic structure layer, dielectric layer and internal conductor layer) and screen printing technology, the goal of maintaining excellent performance in a high current environment is achieved. At the same time, by opening a conductive channel to achieve electrical connection, and performing laser trimming and surface plating, the integration, reliability and stability of the magnetic beads are improved, providing high-performance magnetic beads for high-current applications in modern electronic devices. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 is an exploded view of the magnetic beads of the present invention; Figure 2 is a cross-sectional view of the magnetic bead of the present invention; Figure 3 is a cross-sectional view of the magnetic bead of the present invention from another perspective; Figure 4 It is a structural schematic diagram of the laser processing equipment of the present invention; Figure 5 It is a schematic structural diagram of a cutting unit of the present invention; Figure 6 It is a schematic structural diagram of the grinding machine of the present invention; Figure 7 The figure is a flow chart of the manufacturing process of the magnetic beads of the present invention.

[0027] Reference numerals include: 1. Magnetic structure layer; 2. Internal conductor layer; 3. Dielectric layer; 4. First connector; 5. Second connector; 6. Laser processing equipment; 8. Processing table; 9. Positioning fixture; 11. Control center; 12. Cleaning unit; 13. Conductive channel; 14. Cutting unit; 15. Base; 16. Grinding motor; 17. Grinding part; 18. Discharging part; 19. Sliding guide rail; 21. Slide rail motor; 22. Temperature measuring unit; 23. Heating unit; 100. Limiting protrusion; 200. Limiting groove. DETAILED DESCRIPTION

[0028] In order to facilitate the understanding of those skilled in the art, the present invention is further described below in conjunction with embodiments and drawings. The contents mentioned in the implementation modes are not intended to limit the present invention.

[0029] See also Figures 1 to 7As shown, a magnetic bead based on nickel-zinc ferrite material of the present invention comprises a plurality of magnetic structural layers 1 stacked together, wherein the magnetic structural layer 1 has four layers, an internal conductor layer 2 is arranged on one side of the second magnetic structural layer 1 close to the first magnetic structural layer 1, a side of the third magnetic structural layer 1 close to the first magnetic structural layer 1, and a side of the fourth magnetic structural layer 1 close to the first magnetic structural layer 1, and a dielectric layer 3 is arranged on one side of the second magnetic structural layer 1 close to the first magnetic structural layer 1 and a side of the fourth magnetic structural layer 1 close to the first magnetic structural layer 1; at least a portion of the internal conductor layer 2 is surrounded by the dielectric layer 3, the thickness of the internal conductor layer 2 is greater than the thickness of the dielectric layer 3, the free end of the internal conductor layer 2 protrudes out of the free end of the dielectric layer 3, and the height difference between the dielectric layer 3 and the internal conductor layer 2 can form a gap in the magnetic bead, and the gap is used to interrupt the magnetic path so that a sufficiently high impedance can be presented when a large current is flowing, so as to effectively prevent or attenuate the passage of large current noise, and convert the large current noise into heat energy consumed inside the magnetic bead; A limiting protrusion 100 is provided on one side of the second magnetic structural layer 1 close to the first magnetic structural layer 1, a side of the third magnetic structural layer 1 close to the first magnetic structural layer 1 and a side of the fourth magnetic structural layer 1 close to the first magnetic structural layer 1, a limiting groove 200 used in conjunction with the limiting protrusion 100 is provided on one side of the first magnetic structural layer 1 close to the fourth magnetic structural layer 1, a side of the second magnetic structural layer 1 close to the fourth magnetic structural layer 1 and a side of the third magnetic structural layer 1 close to the fourth magnetic structural layer 1, the magnetic structural layer 1 is laminated and stacked into a laminated structure via the limiting protrusion 100 and the limiting groove 200, and the laminated structure is an integrated magnetic bead product.

[0030] Nickel-zinc ferrite, as the material of magnetic structure layer 1, has the characteristics of low coercivity, high magnetic permeability and high operating frequency band, which enables the magnetic beads to maintain excellent performance in high current environments. Compared with traditional high current current sensor core materials (such as Permalloy, amorphous alloy and manganese-zinc ferrite, etc.), nickel-zinc ferrite can support higher operating frequencies and meet the needs of modern electronic devices for magnetic beads.

[0031] By adopting a multi-layer magnetic structure layer 1 and a specific internal conductor layer 2 and a dielectric layer 3 configuration, the magnetic beads can show better performance under high current. This design helps to reduce energy loss under high current and improve the efficiency of the magnetic beads. Inside the magnetic beads, the dielectric layer 3 is surrounded by the internal conductor layer 2 and a gap is formed, interrupting the magnetic path. This design enables the magnetic beads to maintain a higher magnetic bead value or impedance when subjected to a large DC bias, thereby ensuring that the magnetic beads can maintain stable performance under a wide range of working conditions. By providing a limiting protrusion 100 and a limiting groove 200 on each magnetic structure layer 1, the layers can be tightly pressed together to form a laminated structure. This design not only improves the structural strength of the magnetic beads, but also ensures precise alignment and close contact between the layers, thereby improving the reliability and durability of the magnetic beads. By adopting a standardized limiting protrusion 100 and a limiting groove 200 design, the manufacturing and assembly process of the magnetic beads can be simplified. This design makes the alignment and fixation between the layers easier and more accurate, reduces manufacturing costs and improves production efficiency.

[0032] The magnetic structure layer 1 is nickel-zinc ferrite, and the thickness of the magnetic structure layer 1 is 50-300um. The thickness of the magnetic structure layer 1 is precisely controlled within the range of 50-300 microns (um), and this design helps to optimize the performance of the magnetic beads. The appropriate thickness not only helps to ensure that the magnetic beads have sufficient magnetic bead quantity and impedance, but also maintains its structural stability and reliability.

[0033] The internal conductor layer 2 is a silver paste layer, and the thickness of the internal conductor layer 2 is 200um. Silver, as a metal with excellent conductivity, makes the internal conductor layer 2 have excellent conductivity. The silver paste material has good processability and is easy to be evenly coated on the magnetic structure layer 1 through processes such as screen printing. While maintaining high performance, the 200-micron thickness design also optimizes the space utilization of the magnetic beads, which helps to improve the overall performance and reliability of the device.

[0034] The dielectric layer 3 is a dielectric ceramic layer, and the thickness of the dielectric layer 3 is 5-50um. The dielectric layer 3 is made of dielectric ceramic material, which has a high dielectric constant and stable physical and chemical properties; the high dielectric constant helps to enhance the capacitance effect of the magnetic beads, thereby maintaining stable magnetic bead performance and impedance characteristics under high current environments. At the same time, dielectric ceramics, as an excellent insulating material, can ensure that the dielectric layer 3 has good insulation properties under high current environments; the dielectric layer 3 of appropriate thickness not only helps to maintain the insulation properties of the dielectric layer 3, but also ensures that the gap between it and the internal conductor layer 2 is large enough to interrupt the magnetic path and maintain high magnetic beads or impedance.

[0035] The magnetic bead also includes a first connector 4 arranged on the side of the second magnetic structural layer 1 close to the first magnetic structural layer 1, and a second connector 5 is arranged on the side of the fourth magnetic structural layer 1 close to the third magnetic structural layer 1. A conductive channel 13 is arranged between the first connector 4 and the second connector 5. The conductive channel 13 is opened on the magnetic structural layer 1, and the conductive channel 13 is used to fill the conductive material. The first connector 4 is used to connect the internal conductor layer 2 on the second magnetic structural layer 1 and the internal conductor layer 2 on the third magnetic structural layer 1; the second connector 5 is used to connect the internal conductor layer 2 on the third magnetic structural layer 1 and the internal conductor layer 2 on the fourth magnetic structural layer 1.

[0036] The first connector 4 and the second connector 5 are respectively used to conduct the internal conductor layers 2 on different layers of the magnetic structure layer 1, thereby realizing the electrical connection between the multiple layers of internal conductor layers 2. By directly opening the conductive channel 13 on the magnetic structure layer 1 and filling it with conductive material, the use of additional connecting wires or connectors can be avoided, which helps to reduce the volume and weight of the magnetic bead and improve its integration and portability.

[0037] The conductive material includes the following substances in parts by weight: 5-7 parts of inorganic powder composed of metal magnetic powder, 3-5 parts of lead-free glass powder, 1-2 parts of organic carrier and 1-2 parts of auxiliary agent; the inorganic powder includes at least one of iron-silicon-aluminum alloy, iron-nickel alloy, iron-silicon alloy, carbonyl iron powder and molybdenum-permalloy; the lead-free glass powder includes the following substances in parts by weight: 1-3 parts of lithium oxide, 1-4 parts of potassium oxide, 15-20 parts of boron trioxide, 15-25 parts of bismuth oxide and 35-50 parts of silicon dioxide; the organic carrier includes the following substances in parts by weight: 10-20 parts of high boiling point solvent and 1-3 parts of binder; the auxiliary agent includes the following substances in parts by weight: 1-3 parts of dispersant, 1-2 parts of plasticizer, 2-3 parts of thixotropic agent and 2-3 parts of coupling agent.

[0038] The through hole shape on the conductive channel 13 is circular, triangular, elliptical or quadrilateral, and the through hole shape is selected according to actual needs.

[0039] A process for manufacturing a magnetic bead based on nickel-zinc ferrite material comprises the following steps: S1, pretreatment: preparing a magnetic structural layer 1, using nickel-zinc ferrite powder and a bonding additive to mix into a magnetic material slurry, the magnetic material slurry is made into a raw ceramic sheet by a tape casting process, and the raw ceramic sheet is cut into magnetic structural layers 1 of the same size by a laser cutting process; S2, printing the internal conductor layer 2: select silver paste as the material of the internal conductor layer 2, mix the silver paste with the ink solvent in proportion to form a conductive paste with appropriate viscosity and fluidity, use screen printing technology to evenly print the conductive paste on the magnetic structure layer 1 for multiple times, and bake the conductive paste after it is printed to 200um; S3, printing dielectric layer 3: mixing the prepared dielectric ceramic powder and ink additives to form a printing paste with appropriate viscosity and fluidity; applying it on the magnetic structure layer 1 on which the internal conductor layer 2 has been printed by screen printing, and drying it to enhance the bonding force between the printed dielectric layer 3 and the magnetic structure layer 1; S4, stacking: the stacking mechanism precisely positions the multi-layer magnetic structure layer 1 according to the preset arrangement structure, stacks them and puts them into the mold, and after stacking, a stacked body is formed, and the stacked body is placed in a high-temperature resistant nylon composite film bag, which is evacuated to -0.1 MPa and sealed, and deionized water is injected into the rigid mold cavity, and the high-temperature resistant nylon composite film bag with the stacked body placed is immersed in the rigid mold cavity, and the hot pressing mechanism heats and pressurizes the water in the rigid mold cavity so that the layers of raw embryos in the stacked body are fused to form a whole; S5, debinding: Put the laminate into the debinding furnace, and decompose and remove the colloidal substances in the green body by slow and uniform heating, so as to reduce the product cracking caused by the violent decomposition and gasification of such substances during the sintering process; S6, sintering: placing the debinding laminate into a sintering furnace, and subjecting the laminate to high-temperature sintering to make it dense; S7, silver end: silver paste is applied to the ends of both sides of the sintered laminate and cured to form a conductive silver end layer for the convenience of product welding; S8, electroplating: electroplating the silver layer at both ends of the product with tin and nickel to improve the oxidation resistance, wear resistance and solderability of the product ends.

[0040] Between S2 and S3, step S2.1 is also included: Opening a conductive channel 13: installing the first connector 4 on the free end of the internal conductor layer 2 on the fourth magnetic structure layer 1, and installing the second connector 5 on the free end of the internal conductor layer 2 on the third magnetic structure layer 1; using laser cutting to open a conductive channel 13 on the magnetic structure layer 1 and the internal conductor layer 2, and then filling the conductive material into the opened conductive channel 13 to form an electrical connection; A process for manufacturing magnetic beads based on nickel-zinc ferrite material, wherein S1 further comprises S1.1: The laser cutting system in the laser processing equipment draws the parameters of the raw ceramic piece and forms a cutting code waiting for the cutting operation.

[0041] The S1.1 also includes S1.1.1: (a) The raw ceramic sheet is loaded onto a processing table 8 via a loading mechanism of a laser processing device 6. A positioning fixture 9 is provided on the processing table 8 to position the raw ceramic sheet on the processing table 8 and wait for the next step; (b) The laser processing equipment 6 includes a control center 11 and a cutting unit 14. The control center 11 sets the cutting path, feed rate, and rotation speed of the cutter according to the cutting code formed by the cutting size drawn by the laser cutting system to drive the cutting unit 14 to cut the green ceramic sheet.

[0042] A process for manufacturing magnetic beads based on nickel-zinc ferrite material, further comprising the following steps: S9. Defect detection: The laminated structure is placed into the detection system. The detection system is equipped with a high-resolution industrial camera to automatically locate and detect the laminated structure. The laminated structure that passes the inspection will be shipped out, and the unqualified laminated structure will be transported to the defective product station for reprocessing.

[0043] The line width of the printed internal conductor layer 2 is in the range of 0.5-1.5 mm, and the line width of the side of the internal conductor layer 2 away from the dielectric layer 3 and the magnetic structure layer 1 is in the range of 0.2-0.6 mm.

[0044] The line width of the inner conductor layer 2 is designed to be within the range of 0.5-1.5 mm, which helps to ensure the uniform distribution of current in the conductor layer, reduce the loss and interference of electromagnetic energy, and thus improve the electromagnetic performance of the magnetic beads. At the same time, the line width design coordinated with the magnetic structure layer 1 can further optimize the magnetic bead value and quality factor of the magnetic beads to meet the needs of specific application scenarios.

[0045] The S1 pretreatment to prepare the magnetic structure layer 1 also includes the following steps: (a) breaking up the nickel-zinc ferrite by a breaking mechanism and then putting it into a grinder for multiple grinding to form nickel-zinc ferrite powder; (b) The ground nickel-zinc ferrite powder is placed in a screening mechanism for screening and then waits for the next step.

[0046] The grinding machine includes a base 15, a grinding motor 16, a grinding part 17 and a discharge part 18. The output end of the grinding motor 16 is connected to the grinding part 17. The grinding part 17 is arranged above the discharge part 18. The grinding motor 16 drives the grinding part 17 to rotate to grind the metal magnetic slurry placed in the discharge part 18. The base 15 is also provided with a sliding guide rail 19 and a sliding guide motor 21. The grinding part 17 is installed on the base 15 via the sliding guide rail 19. The sliding guide motor 21 drives the grinding part 17 to move back and forth up and down along the sliding guide rail 19. When grinding is in progress, the sliding guide motor 21 drives the grinding part 17 to approach the discharge part 18. When grinding is finished, the sliding guide motor 21 drives the grinding part 17 to move upward away from the discharge part 18.

[0047] The grinding machine further includes a temperature measuring unit 22 and a heating unit 23. The heating unit 23 is disposed on the discharge portion 18 and is used to heat the metal magnetic slurry placed in the discharge portion 18 to prevent the metal magnetic slurry from agglomerating and ensure the uniformity and stability of the slurry.

[0048] The above contents are only preferred embodiments of the present invention. For ordinary technicians in this field, according to the concept of the present invention, there will be changes in the specific implementation methods and application scopes. The content of this specification should not be understood as limiting the present invention.

Claims

1. A magnetic bead based on nickel-zinc ferrite material, characterized in that: The invention comprises a plurality of magnetic structural layers (1) stacked together, wherein the magnetic structural layer (1) comprises four layers, an internal conductor layer (2) is arranged on a side of the second magnetic structural layer (1) close to the first magnetic structural layer (1), a side of the third magnetic structural layer (1) close to the first magnetic structural layer (1) and a side of the fourth magnetic structural layer (1) close to the first magnetic structural layer (1), and a dielectric layer (3) is arranged on a side of the second magnetic structural layer (1) close to the first magnetic structural layer (1) and a side of the fourth magnetic structural layer (1) close to the first magnetic structural layer (1); at least a portion of the internal conductor layer (2) is surrounded by the dielectric layer (3), the thickness of the internal conductor layer (2) is greater than the thickness of the dielectric layer (3), the free end of the internal conductor layer (2) protrudes from the free end of the dielectric layer (3), and a gap is formed between the dielectric layer (3) and the internal conductor layer (2), and the gap is used to interrupt the magnetic path; A limiting protrusion (100) is provided on one side of the second magnetic structure layer (1) close to the first magnetic structure layer (1), a side of the third magnetic structure layer (1) close to the first magnetic structure layer (1), and a side of the fourth magnetic structure layer (1) close to the first magnetic structure layer (1); a limiting groove (200) used in conjunction with the limiting protrusion (100) is provided on one side of the first magnetic structure layer (1) close to the fourth magnetic structure layer (1), a side of the second magnetic structure layer (1) close to the fourth magnetic structure layer (1), and a side of the third magnetic structure layer (1) close to the fourth magnetic structure layer (1); the magnetic structure layers (1) are laminated via the limiting protrusion (100) and the limiting groove (200) to form a laminated structure.

2. The magnetic bead based on nickel-zinc ferrite material according to claim 1, characterized in that: The magnetic structure layer (1) is nickel-zinc ferrite, and the thickness of the magnetic structure layer (1) is 50-300 um.

3. The magnetic bead based on nickel-zinc ferrite material according to claim 1, characterized in that: The internal conductor layer (2) is a silver paste layer, and the thickness of the internal conductor layer (2) is 200 um.

4. The magnetic bead based on nickel-zinc ferrite material according to claim 1, characterized in that: The dielectric layer (3) is a dielectric ceramic layer, and the thickness of the dielectric layer (3) is 5-50 um.

5. The magnetic bead based on nickel-zinc ferrite material according to claim 1, characterized in that: The magnetic bead further comprises a first connector (4) arranged on a side of the second magnetic structure layer (1) close to the first magnetic structure layer (1), and a second connector (5) arranged on a side of the fourth magnetic structure layer (1) close to the third magnetic structure layer (1); a conductive channel (13) is arranged between the first connector (4) and the second connector (5); the conductive channel (13) is opened on the magnetic structure layer (1); the conductive channel (13) is used to fill conductive material; the first connector (4) is used to conduct the internal conductor layer (2) on the second magnetic structure layer (1) and the internal conductor layer (2) on the third magnetic structure layer (1); the second connector (5) is used to conduct the internal conductor layer (2) on the third magnetic structure layer (1) and the internal conductor layer (2) on the fourth magnetic structure layer (1).

6. A process for producing magnetic beads based on nickel-zinc ferrite material, comprising the following steps: S1, pretreatment: preparing a magnetic structural layer (1), using nickel-zinc ferrite powder and a bonding additive to mix into a magnetic material slurry, the magnetic material slurry is formed into a green ceramic sheet by a tape casting process, and the green ceramic sheet is cut into magnetic structural layers (1) of the same size by a laser cutting process; S2, printing the internal conductor layer: selecting silver paste as the material of the internal conductor layer (2), mixing the silver paste with ink solvent in proportion to form a conductive paste with appropriate viscosity and fluidity, using screen printing technology to evenly stack the conductive paste on the magnetic structure layer (1) in multiple times, and baking the conductive paste after it is stacked to 200 um; S3, printing dielectric layer: mixing the prepared dielectric ceramic powder and ink additive to form a printing paste with appropriate viscosity and fluidity; applying the printed dielectric layer (3) to the magnetic structure layer (1) on which the internal conductor layer (2) has been printed by screen printing, and drying the printed dielectric layer (3) to enhance the bonding force between the magnetic structure layer (1); S4, stacking: the stacking mechanism precisely positions the multiple magnetic structural layers (1) according to the preset arrangement structure, stacks them, and then puts them into the mold. After stacking, a stacked body is formed. The stacked body is placed in a high-temperature resistant nylon composite film bag, which is evacuated to -0.1 MPa and then sealed. Deionized water is injected into the rigid mold cavity, and the high-temperature resistant nylon composite film bag with the stacked body placed is immersed in the rigid mold cavity. The hot pressing mechanism heats and pressurizes the water in the rigid mold cavity so that the layers of raw embryos in the stacked body are fused to form a whole. S5, debinding: Put the laminate into the debinding furnace, and decompose and remove the colloidal substances in the green body by slow and uniform heating, so as to reduce the product cracking caused by the violent decomposition and gasification of such substances during the sintering process; S6, sintering: placing the debinding laminate into a sintering furnace, and subjecting the laminate to high-temperature sintering to make it dense; S7, silver end: silver paste is applied to the ends of both sides of the sintered laminate and sintered to form a conductive silver end layer for the convenience of product welding; S8, electroplating: electroplating the silver layer at both ends of the product with tin and nickel to improve the oxidation resistance, wear resistance and solderability of the product ends.

7. The process for manufacturing magnetic beads based on nickel-zinc ferrite material according to claim 6, characterized in that: Between S2 and S3, step S2.1 is also included: Opening a conductive channel: installing a first connector (4) on the free end of the internal conductor layer (2) on the fourth magnetic structure layer (1), and installing a second connector (5) on the free end of the internal conductor layer (2) on the third magnetic structure layer (1); using laser cutting to open a conductive channel (13) on the magnetic structure layer (1) and the internal conductor layer (2), and then filling the opened conductive channel (13) with conductive material to form an electrical connection.

8. The process for manufacturing magnetic beads based on nickel-zinc ferrite material according to claim 6, characterized in that: The S1 also includes S1.1: The laser cutting system in the laser processing equipment (6) draws the parameters of the raw ceramic piece and forms a cutting code to wait for the cutting operation.

9. The process for manufacturing magnetic beads based on nickel-zinc ferrite material according to claim 8, characterized in that: The S1.1 also includes S1.1.1: (a) loading the raw ceramic sheet onto a processing table (8) via a loading mechanism of a laser processing device (6), wherein a positioning fixture (9) is provided on the processing table (8) to position the raw ceramic sheet on the processing table (8) and wait for the next step; (b) The laser processing equipment (6) includes a control center (11) and a cutting unit (14). The control center (11) sets the cutting path, feed rate, and rotation speed of the cutter according to the cutting code formed by the cutting size drawn by the laser cutting system to drive the cutting unit (14) to cut the raw ceramic sheet.

10. The process for manufacturing magnetic beads based on nickel-zinc ferrite material according to claim 6, characterized in that: The following steps are also included: S9. Defect detection: The laminated structure is placed into the detection system. The detection system is equipped with a high-resolution industrial camera to automatically locate and detect the laminated structure. The laminated structure that passes the inspection will be shipped out, and the unqualified laminated structure will be transported to the defective product station for reprocessing.

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