CN112635153A - Method and device for casting orientation molding of circular magnetic sheet and product - Google Patents
Method and device for casting orientation molding of circular magnetic sheet and product Download PDFInfo
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F13/00—Apparatus or processes for magnetising or demagnetising
- H01F13/003—Methods and devices for magnetising permanent magnets
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F41/00—Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties
- H01F41/02—Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties for manufacturing cores, coils, or magnets
- H01F41/0253—Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties for manufacturing cores, coils, or magnets for manufacturing permanent magnets
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Abstract
The invention discloses a tape casting orientation forming device for a circular magnetic sheet, which comprises a base, a driving motor, a slurry guide pipe, a driving shaft, a circular turntable, a clamping groove and a permanent magnet, wherein the driving motor is arranged on the base; the permanent magnet is arranged in the clamping groove, the clamping groove and the circular turntable rotate along with the driving shaft, and the circle centers of the driving shaft, the circular turntable, the clamping groove and the permanent magnet are positioned on the same straight line; the circular turntable is made of a magnetic conductive material; the outlet of the slurry conduit guides the magnetic slurry to the circle center part, and the slurry rotates along with the circular turntable and expands to the periphery. The invention discloses a tape casting orientation forming method adopting the device and a prepared circular magnetic sheet. According to the invention, the preparation device and the preparation process are synchronously improved, the permanent magnet is adopted to replace an electromagnet, the volume and the power consumption of equipment are greatly reduced, the interaction of a static magnetic field and a centrifugal force is utilized, the orientation of the magnetic filler is rapidly completed in the slurry rotation process, the orientation is fixed and points to the circle center of the magnetic sheet, and the prepared magnetic sheet material has high comprehensive performance.
Description
Technical Field
The invention relates to the technical field of magnetic material manufacturing, in particular to a method, a device and a product for casting and orienting a circular magnetic sheet.
Background
The magnetic anisotropy can be obtained by molding the magnetic material in a magnetic field, so that the performance is improved. Magnetic materials such as ferrite are subjected to magnetic field orientation molding during molding, and after sintering, crystal orientation arrangement of crystal grains is more ordered, so that the magnetic material has stronger magnetic anisotropy. The anisotropy enhancement can greatly improve the performance of the ferrite material. Such as strontium ferrite, generally adopts a way of applying a magnetic field in the process of compression molding. The application mode is that a coil is sleeved outside a mould, and a magnetic field is generated by current. The magnetic field direction is perpendicular to the coil plane. The saturation magnetization and the coercive force of the strontium ferrite formed by the magnetic field can be improved by more than 50% in the magnetic field forming direction.
For a planar hexagonal ferrite magnetic material, the crystal grains are hexagonal sheets and have strong in-plane anisotropy, if the crystal grains are arranged in parallel, the magnetic permeability of the material is increased by three times, and in addition, strong coupling action is generated among the crystal grains, so that the loss in a pass band is reduced to 10 percent of the original loss. However, there is a difficulty in the orientation of the planar hexaferrite, which is a strong in-plane anisotropy unlike the uniaxial anisotropy of strontium ferrite. If the parallel arrangement of crystal grain planes cannot be realized only by a uniform magnetic field in one direction, at least two magnetic fields with crossed directions are needed to obtain one plane. So that the planar hexaferrite cannot be oriented in a similar manner to the strontium ferrite.
In order to solve the problem, the chinese patent application CN201911110135.2 discloses a ferrite raw material sheet forming apparatus and a forming method thereof, wherein the forming apparatus comprises a rotating uniform coating device and a constant magnetic field generating device, the rotating uniform coating device comprises a rotating disk with controllable rotating speed, a PET film with the same size is arranged above the rotating disk with controllable rotating speed, and the surface of the rotating disk with controllable rotating speed is also provided with air holes for adsorbing the PET film; the constant magnetic field generating device is composed of an electromagnet with a rectangular cross section, and the direction of the generated constant magnetic field after electrification is vertical to the cross section; the rotary uniform coating device is arranged between two pole heads of the constant magnetic field electromagnet, and the direction of the magnetic field is parallel to the rotary disk. The present invention adopts a pair of electromagnets to form uniform magnetic field in one region, and adopts a mode of rotary uniform coating in the region to form. In order to obtain a uniform magnetic field, the electromagnet with a large size is needed, the equipment has a large volume and a large weight, the manufacturing cost is high, the system is complex, the energy consumption is high, in addition, because the direction of the magnetic field is parallel to the rotating direction of the disc, the oriented directions of the magnetic powder materials in the slurry are inconsistent in the continuous rotating process of the disc, and because the specific gravity of the magnetic powder materials is greater than other components of the slurry, the magnetic powder materials can rapidly move outwards from the circle center position of the disc under the action of centrifugal force, so the distribution of the powder materials at all positions of the finally manufactured magnetic sheets is uneven.
Disclosure of Invention
The invention aims to provide a casting orientation forming method, a device and a product of a circular magnetic sheet aiming at the problems of complicated structure, large size, heavy weight, high power consumption, unfixed orientation direction, uneven distribution of magnetic materials and the like of the forming equipment.
In order to achieve the purpose, the invention provides the following technical scheme:
a tape casting orientation forming device for a circular magnetic sheet is characterized by comprising a base, a driving motor, a slurry guide pipe, a driving shaft, a circular turntable, a clamping groove and a permanent magnet, wherein the driving shaft, the circular turntable, the clamping groove and the permanent magnet are arranged on the base; the diameters of the driving shaft, the permanent magnet, the clamping groove and the circular turntable are sequentially increased; the circular turntable is made of magnetic conductive materials and is used for guiding the magnetic field of the permanent magnet to the edge of the permanent magnet from the circle center of the permanent magnet; the permanent magnet and the magnetic conduction round turntable are arranged on the upper surface of the round turntable and form a magnetic field with the strongest central position and gradually weakened towards the periphery together; the slurry guide pipe is arranged right above the circular turntable, an outlet of the slurry guide pipe faces the circle center of the circular turntable, and magnetic slurry is guided into the circle center, so that the slurry rotates along with the circular turntable and flows and expands around under the combined action of magnetic field force, centrifugal force and gravity.
The upper surface of the circular turntable is also covered with a layer of PET film which is used as a substrate for bearing slurry and prepared casting films.
The circular turntable is a metal disc with the diameter of 400-500 mm and the thickness of 2-4 mm.
The diameter of the permanent magnet is 40-50 mm, and the height of the permanent magnet is 10-20 mm.
The magnetic pole direction of the permanent magnet is that the N pole is upward and the S pole is downward; the surface magnetic field intensity is 100 to 500 Oe.
The casting orientation forming method of the circular magnetic sheet by adopting the device is characterized by comprising the following steps:
(1) preparing magnetic slurry, wherein the magnetic slurry comprises a long magnetic filler;
(2) arranging a tape casting orientation forming device of a circular magnetic sheet, covering a layer of PET film on the upper surface of a circular turntable of the tape casting orientation forming device, and using the PET film as a substrate for bearing the magnetic slurry and the prepared tape casting film; the circular turntable guides the magnetic field of the permanent magnet to the periphery from the circle center part, and a magnetic field with the strongest central position and gradually weakened to the periphery is formed on the upper surface of the circular turntable;
(3) starting a motor, driving a shaft to drive the circular turntable, the clamping groove and the permanent magnet to rotate together, and reaching a set rotating speed;
(4) magnetic slurry is led into the circle center part through an outlet of a slurry guide pipe which is arranged right above the circular turntable and faces to the circle center part of the circular turntable, and the magnetic slurry flows, expands and flattens around under the combined action of centrifugal force, magnetic force of a magnetic field and gravity to start tape casting; the magnetic filler in the slurry flows and expands to the periphery together with the slurry under the combined action of the outward centrifugal force of the rotation of the turntable, the inward magnetic force of the magnetic field of the permanent magnet and the gravity, and the axis of the particles of the slurry faces to the center of a circle in the process to finish the orientation arrangement;
(5) keeping the driving shaft at a uniform rotating speed, continuously introducing, casting and orienting the slurry by the slurry guide pipe until the thickness of the casting film on the substrate reaches a set thickness, stopping introducing the magnetic slurry, then stopping the rotation of the circular turntable, curing and drying to obtain an anisotropic circular magnetic sheet formed by orientation;
(6) and cutting the formed circular magnetic sheet by using a die to remove a part of area close to the center of the circular magnetic sheet and a part of area close to the outer edge of the circular magnetic sheet to form the circular magnetic sheet.
The rotating speed set in the step (3) is 60-180 revolutions per minute.
And (5) stopping casting when the thickness of the casting film in the step (5) reaches the set thickness of 0.2-0.8 mm, so that the dried film thickness is 0.1-0.7 mm.
The magnetic filler is one of magnetic long ellipsoidal particles, rod-shaped particles or short fibers.
A circular magnetic sheet prepared by the tape casting orientation forming method is characterized in that: the orientation arrangement directions of the magnetic fillers in the circular magnetic sheets are consistent and all point to the circle center of the circular magnetic sheets; the distribution uniformity of the magnetic fillers at all positions is good.
Compared with the prior art, the invention has the beneficial effects that:
(1) according to the tape casting orientation forming method, device and product of the circular magnetic sheet, provided by the invention, the preparation process and device are synchronously improved, the permanent magnet is adopted to replace the electromagnet, the structure is reasonably designed, and the volume and the power consumption of equipment are greatly reduced; the permanent magnet forms a static magnetic field at the center of the circular turntable, the magnetic field is transmitted to the periphery by the circular turntable made of magnetic conductive materials, and the magnetic field with the strongest central part and gradually weakened to the periphery is formed on the circular turntable; the magnetic field attracts the magnetic filler particles in the slurry to the circle center, the centrifugal force generated by the rotation of the circular turntable pushes the magnetic filler particles away from the circle center, and the magnetic filler particles interact with each other to quickly complete the orientation of the magnetic filler in the rotation process of the slurry, and the orientation of the magnetic filler particles is fixed and points to the circle center of the magnetic sheet.
(2) Compared with the existing device which uses an electromagnet to provide a magnetic field, the device provided by the invention has the advantages of compact structure, small volume, light weight and low cost; the size is reduced to 1/3 in the prior art, the weight is reduced to 1/10 in the prior art, the power consumption of the device is 1/20 in the prior art, and the cost is 1/40 in the prior art.
(3) The product produced by the device and the process provided by the invention has good uniformity of magnetic filler particle distribution, magnetization and orientation directions at all positions, good consistency of material performance at all positions, and controllable product performance difference within 3% in different batches, and is beneficial to batch production. Compared with the unoriented formed material, the magnetic permeability of the circular magnetic sheet prepared by the invention with the planar hexagonal ferrite as the magnetic filler is increased from 10-12 to about 30-40 and the loss in a pass band is reduced from 1-2 to 0.1-0.2 after the circular magnetic sheet is subjected to orientation forming by the device.
(4) The device and the method provided by the invention can lead the crystal phase directions of the ferrite powder in the prepared ferrite product to be approximately the same, and the magnetic sheet material prepared by the device and the method has uniform distribution and orientation of the magnetic material and high comprehensive performance. Meanwhile, by adjusting parameters such as magnetic field intensity, rotating speed and the like, the invention can also be suitable for planar hexagonal ferrite, MnZn, NiZn and Co2Z、Co2Y, etc. for molding various soft magnetic green sheets. When the magnetic green sheet produced by the present invention is formed, it is made ofThe raw material powder is formed by adopting crystal orientation, so that the sintered material has higher resonant frequency in the plane direction, the magnetic conductivity is improved, the loss is reduced, and the comprehensive performance can be greatly improved.
Drawings
FIG. 1 is a schematic structural diagram of a circular magnetic sheet casting orientation forming device according to the present invention;
FIG. 2 is a schematic view of the full-section structure of FIG. 1.
FIG. 3 is a schematic top view of the magnetic disk casting orientation forming apparatus of the present invention;
in the figure: 1. a slurry conduit; 2. A circular turntable; 3. A permanent magnet; 4. A card slot; 5. a connecting bolt; 6. a drive shaft.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Referring to fig. 1-3, the casting orientation forming apparatus for a circular magnetic sheet according to the present embodiment includes a base (not shown), a driving motor (not shown), a slurry conduit 1, and a driving shaft 6, a circular turntable 2, a clamping groove 4, and a permanent magnet 3 mounted on the base; the permanent magnet 3 is arranged in a cavity of the clamping groove 4, the lower surface of the clamping groove 4 is arranged on the driving shaft 6, the lower surface of the circular turntable 2 is arranged on the clamping groove 4, the two rotate together with the driving shaft 6, and the centers of circles of the driving shaft 6, the circular turntable 2, the clamping groove 4 and the permanent magnet 3 are on the same straight line; the diameters of the driving shaft 6, the permanent magnet 3, the clamping groove 4 and the circular turntable 2 are sequentially increased; the circular turntable 2 is made of magnetic conductive material and is used for guiding the magnetic field of the permanent magnet 3 from the center of the circle to the edge of the circle; the permanent magnet 3 and the magnetic conduction round turntable 2 are arranged on the upper surface of the round turntable 2 to jointly form a magnetic field which has the strongest central position and gradually weakens towards the periphery; the slurry conduit 1 is arranged right above the circular turntable 2, the outlet of the slurry conduit faces the circle center of the circular turntable 2, and magnetic slurry is guided into the circle center, so that the slurry rotates along with the circular turntable 2 and flows and expands around under the combined action of magnetic field force, centrifugal force and gravity.
The upper surface of the circular turntable 2 is also covered with a layer of PET film which is used as a substrate for bearing slurry and prepared casting films.
The circular turntable 2 is a metal disc with the diameter of 400-500 mm and the thickness of 2-4 mm; the metal material is magnetic conductive iron, stainless steel alloy and other materials. The diameter of the circle center turntable is too small, the internal magnetic field of the circular turntable is not parallel, and the plane of the circular turntable is easy to deform if the diameter of the circle center turntable is too large; the circular turntable is easy to deform when the thickness of the circular turntable is too thin, and the circular turntable is not beneficial to enabling the magnetic fields inside the circular turntable to be parallel when the thickness of the circular turntable is too thick;
the diameter of the permanent magnet 3 is 40-50 mm, and the height is 10-20 mm. The permanent magnet is cylindrical and can be formed by laminating one or more permanent magnets so as to adjust the surface magnetic field intensity; the permanent magnet is concentric with the circular turntable, but the diameter of the permanent magnet is far smaller than that of the circular turntable and is about 1/10 of the circular turntable. The diameter of the magnetic filler can be adjusted according to the processing characteristics of the magnetic filler cast, and the diameter is increased when the magnetic field intensity is required to be increased, and is reduced when the magnetic field intensity is required to be increased. The diameter of the permanent magnet is too small, so that the magnetic field of the circular turntable is too small, and the recovery area in the middle is too large; the height (thickness) of the permanent magnet is too small to be easily demagnetized, and the magnet is too large to be easily processed.
In this embodiment, the magnetic pole direction of the permanent magnet 3 is N pole up and S pole down; the surface magnetic field intensity is 100 to 500 Oe. The magnetic field strength on the surface is too weak, so that the orientation degree is not high, and the magnetic filler in the slurry is absorbed, cannot flow and cannot spread due to too strong magnetic field strength; other embodiments may be modified as desired.
A tape casting orientation forming method of a circular magnetic sheet by adopting the device comprises the following steps:
(1) preparing magnetic slurry, wherein the magnetic slurry comprises a long magnetic filler; the magnetic filler is one of magnetic long ellipsoidal particles, rod-shaped particles or short fibers; the embodiment adopts ferrite powder, including planar hexaferrite powder;
(2) arranging a tape casting orientation forming device of a circular magnetic sheet, covering a layer of PET film on the upper surface of a circular turntable 2 of the tape casting orientation forming device, and using the PET film as a substrate for bearing the magnetic slurry and the prepared tape casting film; the circular turntable 2 guides the magnetic field of the permanent magnet 3 from the center of a circle to the periphery, and a magnetic field with the strongest central position and gradually weakened to the periphery is formed on the upper surface of the circular turntable 2;
(3) starting a motor, and driving a shaft 6 to drive the circular turntable 2, the clamping groove 4 and the permanent magnet 3 to rotate together and reach a set rotating speed;
(4) magnetic slurry is led into the center of a circle of the circular turntable 2 through an outlet of a slurry conduit 1 which is arranged right above the circular turntable and faces the center of the circle, and the magnetic slurry flows, expands and flattens around under the combined action of centrifugal force, magnetic force of a magnetic field and gravity to start tape casting; the magnetic filler in the slurry flows and expands to the periphery together with the slurry under the combined action of the outward centrifugal force of the rotation of the turntable, the inward magnetic force of the magnetic field of the permanent magnet and the gravity, and the axis of the particles of the slurry faces to the center of a circle in the process to finish the orientation arrangement;
(5) keeping the driving shaft 6 at a uniform rotating speed, continuously introducing, casting and orienting the slurry by the slurry guide pipe 1 until the thickness of the casting film on the substrate reaches a set thickness, stopping introducing the magnetic slurry, stopping the rotation of the circular turntable 2, curing and drying to obtain an anisotropic circular magnetic sheet formed by orientation;
(6) and cutting the formed circular magnetic sheet by using a die to remove a part of area close to the center of the circular magnetic sheet and a part of area close to the outer edge of the circular magnetic sheet to form the circular magnetic sheet.
In this embodiment, the dimensions of the removed portions of the circular magnetic sheet after the molding are as follows: if the inner circle with the diameter of 30-60mm close to the circle center is removed too little, the orientation direction of the part close to the circle center deviates from the direction pointing to the circle center, and if the inner circle is removed too much, the productivity is too low, and the waste is serious; the outer dimensions removed can be determined by the thickness of the circular magnetic sheet (which must meet minimum thickness requirements), and the outer diameter of the desired magnetic green sheet.
In this embodiment, when the thickness of the casting film in the step (5) reaches the set thickness of 0.2mm to 0.8mm, the casting is stopped, and the dried film thickness is 0.1mm to 0.7 mm. In other embodiments, other dimensions can be selected, and the specific dimensions can be selected according to product performance requirements and processing characteristics of the magnetic material, so that the technical effects of the invention can be achieved.
The circular magnetic sheet prepared by the tape casting orientation forming method is characterized in that the orientation arrangement directions of magnetic fillers in the circular magnetic sheet are consistent and all point to the circle center of the circular magnetic sheet.
The magnetic filler of the invention can adopt hexagonal ferrite, MnZn, NiZn and Co2Z、Co2Y, etc.
When the device works, the circular turntable 2 guides the magnetic field of the permanent magnet 3 from the circle center part to the periphery to generate magnetic force for attracting the magnetic filler inwards, and simultaneously rotates at a constant speed to generate outward centrifugal force of the magnetic filler; when the magnetic slurry flows into the PET substrate from the right top of the circle center, the magnetic filler particles (or fibers) flow and expand from the center to the periphery of the outer side under the combined action of magnetic force of a magnetic field and centrifugal force (and gravity), and are gradually spread and air-dried to form a casting film which is solidified, molded and oriented, namely a circular magnetic sheet. And subsequently cutting off the circle center part and the part of the outer edge of the circular magnetic sheet, the thickness of which can not reach the standard, for recycling. The prepared circular magnetic sheet can be further cut, stacked and sintered to be used for preparing magnetic cores of various magnetic elements. According to the characteristics of the magnetic filler, the flow speed, the extension range and the orientation speed of the filler particles of the magnetic slurry can be adjusted by adjusting the strength and the confrontation relation of the magnetic force of the magnetic field and the centrifugal force.
Specific example 1:
the casting orientation forming device for the circular magnetic sheet adopted by the embodiment has the following specific parameters: the diameter of the circular turntable is 400mm, the thickness of the circular turntable is 3mm, the diameter of the permanent magnet is 40mm, the height (thickness) of the circular turntable is 15mm, the surface magnetic field intensity of the magnet is 300 Oe, and the rotating speed control range is 120 r/min.
Preparing magnetic filler powder: chemically pure raw materials are BaCO according to the mass ratio3：CoO：Fe2O3= 3: 2: 12 and pure water with equal mass, ball-milling and mixing for 3 hours, drying and sieving by a 40-mesh sieve, presintering at 1250 ℃, preserving heat for 4 hours, ball-milling until D50=1.0 mu m, drying and sieving by the 40-mesh sieve to obtain ferrite powder for later use.
Preparing magnetic slurry: taking 100 parts of the ferrite powder obtained in the last step, stirring and mixing the ferrite powder with 1 part of triton, 2 parts of dibutyl phthalate, 15 parts of polyvinyl butyral, 70 parts of isobutanol and 30 parts of absolute ethyl alcohol for 3 hours to prepare magnetic slurry to be cast, and sieving the magnetic slurry with a 60-mesh sieve for later use.
Tape casting and shaping: by adopting the device, firstly, a layer of 0.015mm PET film is pasted on a circular turntable, a motor is started to enable the rotating speed of the turntable to reach 120 r/min, magnetic slurry is introduced to start tape casting, magnetic fillers in the slurry uniformly move towards the periphery (flow along with the slurry) and are oriented in the process, and at the moment, a solvent in the slurry is continuously increased, so that the magnetic fillers in the slurry are shaped; and stopping casting when the thickness of the evaporated slurry reaches 0.65mm, (the thickness of the film can reach 0.6mm after further drying), and cutting off an inner circle part with the middle diameter of 60mm by using a cutting die to obtain the circular magnetic sheet with the ring shape.
A small circular ring with the inner diameter of 10mm and the outer diameter of 20mm is punched out of the circular magnetic sheet by using a cutting die to be used as a test sample, and the circular magnetic sheet is fully dried, de-glued and sintered for 2 hours at 1250 ℃ to be used as the magnetism of the magnetic element for testing. The magnetic permeability is 35 + -2 (1-700 MHz), and the loss is 0.15 + -0.05 (1-700 MHz).
Comparative example: the apparatus and process conditions for preparing the test samples were the same, but not according to permanent magnets. The test result shows that the magnetic conductivity is 14 +/-2 (1-700 MHz) and the loss is 2.0 +/-0.5 (1-700 MHz).
The invention mainly solves the problems of complex structure, large size, heavy weight, large power consumption and the like of the existing forming equipment by synchronously improving the device and the preparation process.
Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.
Claims (11)
1. The tape casting orientation forming device for the circular magnetic sheets is characterized by comprising a base, a driving motor, a slurry guide pipe (1), a driving shaft (6), a circular turntable (2), a clamping groove (4) and a permanent magnet (3), wherein the driving shaft (6), the circular turntable (2), the clamping groove (4) and the permanent magnet (3) are arranged on the base; the diameters of the driving shaft (6), the permanent magnet (3), the clamping groove (4) and the circular turntable (2) are sequentially increased; the circular turntable (2) is made of magnetic conductive material and is used for guiding the magnetic field of the permanent magnet (3) to the edge of the permanent magnet from the center of the circle; the permanent magnet (3) and the magnetic circular turntable (2) are arranged on the upper surface of the circular turntable (2) to form a magnetic field which has the strongest central position and gradually weakens towards the periphery; the slurry guide pipe (1) is arranged right above the circular turntable (2), an outlet of the slurry guide pipe faces the circle center of the circular turntable (2), magnetic slurry is guided into the circle center, the slurry rotates along with the circular turntable (2), and flows and expands around under the combined action of magnetic field force, centrifugal force and gravity.
2. A casting orientation molding apparatus for a circular magnetic sheet according to claim 1, characterized in that: the upper surface of the circular turntable (2) is also covered with a layer of PET film which is used as a substrate for bearing slurry and prepared casting films.
3. A casting orientation molding apparatus for a circular magnetic sheet according to claim 1, characterized in that: the circular turntable (2) is a metal disc with the diameter of 400-500 mm and the thickness of 2-4 mm.
4. A casting orientation molding apparatus for a circular magnetic sheet according to claim 1, characterized in that: the diameter of the permanent magnet (3) is 40-50 mm, and the height of the permanent magnet is 10-20 mm.
5. A casting orientation molding apparatus for a circular magnetic sheet according to claim 1, characterized in that: the magnetic pole direction of the permanent magnet (3) is that the N pole is upward and the S pole is downward; the surface magnetic field intensity is 100 to 500 Oe.
6. A casting orientation forming method of a circular magnetic sheet using the apparatus as claimed in any one of claims 1 to 5, characterized by comprising the steps of:
(1) preparing magnetic slurry, wherein the magnetic slurry comprises a long magnetic filler;
(2) arranging a tape casting orientation forming device of a circular magnetic sheet, covering a layer of PET film on the upper surface of a circular turntable (2) of the tape casting orientation forming device, and using the PET film as a substrate for bearing the magnetic slurry and the prepared tape casting film; the circular turntable (2) guides the magnetic field of the permanent magnet (3) to the periphery from the circle center part, and a magnetic field with the strongest central position and gradually weakened to the periphery is formed on the upper surface of the circular turntable (2);
(3) starting a motor, and driving a driving shaft (6) to drive the circular turntable (2), the clamping groove (4) and the permanent magnet (3) to rotate together to reach a set rotating speed;
(4) magnetic slurry is led into the center of a circle of a circular turntable (2) through an outlet of a slurry conduit (1) which is arranged right above the circular turntable and faces the center of the circular turntable (2), and the magnetic slurry flows, expands and flattens around under the combined action of centrifugal force, magnetic force of a magnetic field and gravity to start tape casting; the magnetic filler in the slurry flows and expands to the periphery together with the slurry under the combined action of the outward centrifugal force of the rotation of the turntable, the inward magnetic force of the magnetic field of the permanent magnet and the gravity, and the axis of the particles of the slurry faces to the center of a circle in the process to finish the orientation arrangement;
(5) and (3) keeping the driving shaft (6) at a uniform rotating speed, continuously introducing, casting and orienting the slurry by the slurry guide pipe (1) until the thickness of the casting film on the substrate reaches a set thickness, stopping introducing the magnetic slurry, then stopping the rotation of the circular turntable (2), curing and drying to obtain the anisotropic circular magnetic sheet formed by orientation.
7. A casting orientation forming method of a circular magnetic sheet according to claim 6, characterized in that: it also includes the following steps:
(6) and cutting the formed circular magnetic sheet by using a die to remove a part of area close to the center of the circular magnetic sheet and a part of area close to the outer edge of the circular magnetic sheet to form the circular magnetic sheet.
8. A casting orientation forming method of a circular magnetic sheet according to claim 6, characterized in that: the rotating speed set in the step (3) is 60-180 revolutions per minute.
9. A casting orientation forming method of a circular magnetic sheet according to claim 6, characterized in that: and (5) stopping casting when the thickness of the casting film in the step (5) reaches the set thickness of 0.2-0.8 mm, so that the dried film thickness is 0.1-0.7 mm.
10. A casting orientation forming method of a circular magnetic sheet according to any one of claims 6 to 9, characterized in that: the magnetic filler is one of magnetic long ellipsoidal particles, rod-shaped particles or short fibers.
11. A circular magnetic sheet produced by the casting orientation forming method according to any one of claims 6 to 10, characterized in that: the orientation arrangement directions of the magnetic fillers in the circular magnetic sheets are consistent and all point to the circle center of the circular magnetic sheets.
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Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101162646A (en) * | 2007-05-28 | 2008-04-16 | 深圳市天盈德科技有限公司 | Forming method of annular magnetic body orientating along the direction of radius or diameter radiation |
| CN101503297A (en) * | 2009-02-06 | 2009-08-12 | 中国计量学院 | Tape casting preparation for gradient material in rotating magnetic field |
| CN101656148A (en) * | 2008-08-21 | 2010-02-24 | 阿尔卑斯电气株式会社 | Method of manufacturing magnetic sheet, magnetic sheet, and apparatus for manufacturing magnetic sheet |
| CN203917911U (en) * | 2014-05-27 | 2014-11-05 | 安徽大地熊新材料股份有限公司 | A kind of Nd-Fe-B powder oriented moulding mould |
| CN107545972A (en) * | 2016-06-29 | 2018-01-05 | 比亚迪股份有限公司 | A kind of magnetic fillers oriented alignment technique and its casting device, core material |
| WO2018218077A1 (en) * | 2017-05-24 | 2018-11-29 | California Institute Of Technology | Hypoeutectic amorphous metal-based materials for additive manufacturing |
| CN109148135A (en) * | 2018-08-28 | 2019-01-04 | 横店集团东磁股份有限公司 | It is a kind of to improve the aligning device and its implementation for inhaling wave magnetic sheet magnetic powder |
| CN110787970A (en) * | 2019-11-14 | 2020-02-14 | 湖南工程学院 | Ferrite raw material sheet forming equipment and forming method thereof |
-
2021
- 2021-03-05 CN CN202110242475.1A patent/CN112635153B/en active Active
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101162646A (en) * | 2007-05-28 | 2008-04-16 | 深圳市天盈德科技有限公司 | Forming method of annular magnetic body orientating along the direction of radius or diameter radiation |
| CN101656148A (en) * | 2008-08-21 | 2010-02-24 | 阿尔卑斯电气株式会社 | Method of manufacturing magnetic sheet, magnetic sheet, and apparatus for manufacturing magnetic sheet |
| CN101503297A (en) * | 2009-02-06 | 2009-08-12 | 中国计量学院 | Tape casting preparation for gradient material in rotating magnetic field |
| CN203917911U (en) * | 2014-05-27 | 2014-11-05 | 安徽大地熊新材料股份有限公司 | A kind of Nd-Fe-B powder oriented moulding mould |
| CN107545972A (en) * | 2016-06-29 | 2018-01-05 | 比亚迪股份有限公司 | A kind of magnetic fillers oriented alignment technique and its casting device, core material |
| WO2018218077A1 (en) * | 2017-05-24 | 2018-11-29 | California Institute Of Technology | Hypoeutectic amorphous metal-based materials for additive manufacturing |
| CN109148135A (en) * | 2018-08-28 | 2019-01-04 | 横店集团东磁股份有限公司 | It is a kind of to improve the aligning device and its implementation for inhaling wave magnetic sheet magnetic powder |
| CN110787970A (en) * | 2019-11-14 | 2020-02-14 | 湖南工程学院 | Ferrite raw material sheet forming equipment and forming method thereof |
Non-Patent Citations (1)
| Title |
|---|
| 彭周等: "陶瓷流延颗粒排列的定量图像研究", 《硅酸盐通报》 * |
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