TWI434301B - The hot-forming fabrication method and apparatus of magnetic component - Google Patents

Description

Hot press forming magnetic component manufacturing method and device

The invention relates to a method and a device for manufacturing a hot-pressed magnetic component used in a high-current energy storage inductor, an electronic component and an electromagnetic control component and the like.

In order to overcome the problem of traditional magnetic component winding, the industry has gradually changed the cylindrical core. As shown in the ninth diagram and the traditional open cylindrical core element, the device can form magnetic lines around the current-carrying coil (1). Outside the circle, most of them radiate radially from the center of the core (2). This is the main source of electromagnetic interference (EMI), and its magnetic line paths are exposed to the air, and there is no function to enhance the magnetic field induction.

In order to improve the shortcomings of open magnetic components, the market mostly relies on the addition of an outer cover (3) on the outside of the magnetic core (2). It is commonly known as a combined core element (Drum Core), as shown in the tenth figure, the traditional combined core element As shown in the cross-sectional view, the combined core element has two distinct advantages over the open type element:

1. Increase the external magnetic field strength output by adding magnetic lines of force to the magnetic material path.

2. The outer cover guides the magnetic lines of force into the material of the outer cover to reduce the escape of the magnetic lines.

However, this design still has the problem of component gap (Gap). Due to the assembly method, there must be a component gap (31) in the component (as shown in the slash area in the figure), which will cause more than 50% magnetic loss.

The main purpose of the present invention is to:

1. Applying the hot pressing technology of the present invention to the basic magnetic component, the magnetic material is tightly packaged, so that the finished magnetic energy storage component is finished, thereby solving the problems of the conventional opening dissipation and the component gap.

2. The low magnetic loss high magnetic permeability material and the high electromagnetic wave shielding material developed by the invention are used to improve the performance of the final enhanced component.

In order to achieve the above object, the present invention adopts the following technical solutions:

The invention provides a method for manufacturing a magnetic element hot press forming, which comprises the steps of: forming a current storage coil 1 around a periphery of a magnetic core 2 to form a magnetic energy storage element A, placing it in a mold and putting it around the magnetic energy storage element A The magnetic masking material 4 is subjected to a hot press forming process to obtain a thermoformed magnetic member B coated with a magnetic masking material 4.

The present invention also provides a magnetic element hot press forming apparatus comprising a magnetic core 2, a current carrying coil 1 surrounding the periphery of the magnetic core 2, and a magnetic mask material 4 which is thermally pressed around the core 2 and the current carrying coil 1. The resulting thermoformed magnetic component device.

Comparison of new and old technologies:

The hot pressing technology of the invention mainly heats the molding powder to soften and melt during the heating and pressing process, and the powder is molded into the mold to achieve complex molding such as corner, hollow and minute size.

Conventional cold pressing technology: generally refers to powder press-forming (Press), which is mainly formed by mechanical pressure molding, and then finished by annealing and sintering.

Traditional magnetic components are manufactured using powder cold press molding to The following is a comparison of the hot press forming of the present invention with the conventional cold press forming magnetic technology.

The term "component" as used in the present invention generally refers to a magnetic material that is formed by an additional device such as a coil, a line, or a coating, which can be used as an inductor, an electromagnetic force, etc.; Refers to the magnetic core rod coated in the magnetic element.

As shown in the first figure and the cross-sectional view of the hot-pressed magnetic element of the present invention, the "thermocompression-molded magnetic element" of the present invention comprises: a magnetic core (2), a current-carrying coil (1) surrounding the periphery of the magnetic core (2), and The magnetic core (2) and the current-carrying coil (1) are externally wrapped with a thermocompression-molded magnetic element made of a magnetic shielding material (4).

The magnetic core (2) referred to in the present invention may comprise a composite magnetic material core (2) having a single magnetic or magnetic property with low magnetic loss (Core Loss) and good magnetic permeability (Permeability), and a magnetic shielding material (4). ) refers to a single sheet with high electromagnetic shielding (EMI Shielding) A composite magnetic material magnetic shielding material (4) having different magnetic properties.

When the current-carrying coil (1) passes current, an applied magnetic field is generated to electromagnetically induce the magnetic material of the surrounding magnetic core (2) and the magnetic shielding material (4), thereby enhancing the overall magnetic field output.

As is known, the central region of the current-carrying coil (1) is the region with the highest magnetic flux density. The present invention uses a single or composite magnetic material having different magnetic properties to form a magnetic core (2) having a low magnetic loss characteristic, which is located in a current-carrying coil ( 1) The central area provides the best magnetic line sensing.

When the core magnetic flux density is increased, the magnetic core (2) has a low magnetic loss characteristic, so that the magnetic loss rise can be effectively suppressed, and the magnetic shielding material (4) having a high electromagnetic wave characteristic is coated on the periphery to have magnetic line guiding characteristics, and the magnetic line is effectively accommodated. In the component, electromagnetic interference can be suppressed.

It can be seen from the above that the hot-pressed magnetic component of the present invention has the following three characteristics:

a. Effectively utilize the material properties of the low magnetic loss core (2) and the high electromagnetic wave magnetic shielding material (4) to maximize the magnetic field lines of the component without causing too much electromagnetic interference and magnetic loss.

b. By properly controlling the volume ratio of the low magnetic loss core (2) and the high electromagnetic wave magnetic shielding material (4), the inductance (Inductance) and proper magnetic loss control required for the design can be obtained, usually high magnetic permeability is low. Magnetic loss materials are more expensive than general magnetic materials, and finished products can also be controlled at an appropriate cost.

c. The low magnetic loss core (2) and the high electromagnetic wave magnetic shielding material (4) are tightly coated, which can avoid the joint gap Magnetic field disturbance and magnetic loss increase.

The hot-pressed magnetic component of the invention has the following extension changes, which can develop different magnetic core (2) and magnetic shielding material (4) material ratio according to design and specification requirements, as shown in the second to fifth figures, with the magnetic The core (2) material has an increased volume, which can effectively increase the component inductance and reduce the magnetic loss.

As shown in the second figure, the combination of the magnetic core and the current-carrying coil of the present invention shows a smaller magnetic core (2) and a larger magnetic shielding material (4) volume ratio, which is suitable for low-sensitivity components and high EMI shielding. effect.

The third picture shows the design of the magnetic core (2) protruding current-carrying coil (1). It is found that the magnetic core (2) protrudes from the current-carrying coil (1), which can effectively avoid the problem of magnetic line choking, and the sensitivity is 20~50. % improvement effect.

The fourth figure shows that the magnetic core (2) has a T-shape. This design has the advantage of increasing the surface area and material volume ratio of the magnetic core (2) and the magnetic shielding material (4), which can effectively avoid the magnetic core (2) and magnetic properties. Shielding material (4) Magnetic field loss and lifting sensation of the junction.

The fifth picture shows the material volume ratio of the enlarged magnetic core (2), which can greatly enhance the inductance and reduce the magnetic loss design.

Therefore, the shape of the magnetic core (2) can be a shape of a work shape, a T shape, a column shape, etc., and the coating of the magnetic shielding material (4) can be fully or partially covered by considering the size of the component.

The hot-press forming manufacturing method of the magnetic component of the present invention comprises:

1. Hot press molding powder preparation project:

The hot press molding powder preparation of the present invention comprises the following raw material preparation:

A, magnetic powder: magnetic powder contains Hogonas SC200, SC100.26 Beipiao Shenglong BF200.27, BF100.27 and other iron powder or alloy iron powder (Fe, Al, Si, Cr, Ni, Co) or other similar Magnetically mixed powder (such as Sendust, Amorphous, MPP, Hi-Flux).

B. Bonding agent: The magnetic powder powder uses 4% to 20% by weight of a single or a plurality of unique resins, and is used as a magnetic molecular bonding agent during hot pressing, and the type of resin used may include polycarbonate (PC) and styrene resin. Commonly used hot pressing materials such as (PS), polyethylene (PE), nylon (Nylon), and polypropylene (PP).

C. Lubricant: Lubricant (such as white wax, molybdenum disulfide, PTFE) used according to the weight of magnetic powder (such as white wax, molybdenum disulfide, PTFE), etc., so that the lubrication effect during hot pressing helps to release the mold.

2. Mixing powder project:

The powder mixing project of the invention uses the general single-axis or multi-axial mixer in the industry, and is stirred according to the following working method sequence:

a. Add a single magnetic powder or a variety of magnetic powder and stir until uniform.

b. Repeat a. Process until all magnetic powders have been added and stirred evenly.

c. Add a binder or a plurality of binders and stir until uniform. If the binder is a wet binder (containing a solvent such as ethanol or acetone), it should be mixed to a dry, non-caking condition.

d. Repeat c. Process until all binders have been added and stirred well.

e. Add lubricant and stir until uniform.

f. Repeat e. Process until all lubricants have been added and stirred evenly.

3. Finished powder production project:

a. Confirmation of powder characteristics: After the powder is uniformly mixed, the magnetic permeability, electric resistance value, hysteresis curve, loose density and other characteristics of the powder are measured, and the powder loose density ranges from 2 to 4 g/cm ³ .

b. Powder sieving: The powder will pass through the sieving machine. According to the magnetic requirements, different sizes of sieves are used to screen out the powders of different particle sizes. The particle size range is mainly the mesh of mesh mesh below 80 mesh.

c. Heat treatment: consider the magnetic properties of the powder, the powder packing density, the powder fluidity, the green strength after molding, and sometimes the heat treatment of the powder to improve its magnetic properties and processing characteristics. The heat treatment timing is mainly considered when the powder is hot pressed. When the properties are not good (that is, the appearance has obvious cracks or incomplete coating), the powder may be pre-heat treated at 180~230 °C, so that the bonding agent and the magnetic material are first coated and then used in the hot pressing process.

4. Magnetic powder hot pressing manufacturing:

As shown in the sixth figure, the brief steps of manufacturing the hot-pressed magnetic component of the present invention are as follows:

A. The current-carrying coil (1) is surrounded by the periphery of the magnetic core (2), and the two are combined to produce a magnetic energy storage element (A).

B. The magnetic energy storage element (A) is placed in the cavity, and the magnetic shielding material (4) is put into the magnetic compression molding process to obtain the reinforced hot-pressed magnetic component (B) which is hot-pressed with the magnetic shielding material (4). ).

Therefore, the present invention can refer to the foregoing component design, change or adjust the current carrying. The ratio of the coil (1) and the material surrounding the core (2) reaches the required device specifications. It can be known from the basic physical electromagnetics that the inductance (Inductance) is proportional to the number of coils of the current-carrying coil, and the number of coil turns is increased or decreased. The sensitivity of the device can be adjusted, and when the number of turns changes, the proportion of the included core also changes.

The magnetic powder manufacturing operation and related precautions and parameters of the magnetic powder according to the present invention are as shown in the seventh drawing, the manufacturing process diagram of the magnetic powder hot-pressed magnetic component of the present invention, the eighth drawing, and the heat pressing device diagram of the present invention.

The manufacturing method process is divided into the following actions:

1. Powder barrel (81), material tube (82) and mold (83) heating (71): To ensure the maintenance of the hot pressing characteristics of the powder, the powder barrel (81), the material tube (82) and the mold ( 83) All heaters need to be installed. The heating temperature varies from 140 to 350 °C depending on the area.

2. The combined low magnetic loss core (2) and current carrying coil (1) magnetic energy storage element (A) to be coated in the cavity (72): magnetic energy storage component (A) to be coated From the object to the cavity, the design of the magnetic energy storage component (A) to be coated needs to consider the following points:

a. magnetic energy storage element (A) to be coated or clamped.

b. Magnetic energy storage element (A) where the object to be coated is placed and the hot pressed powder fills the inlet direction.

c. Magnetic energy storage element (A) The object to be coated can withstand the strength design.

d. Magnetic energy storage component (A) demoulding design of the cladding to be coated.

3. Pressing device (84) performs hot pressing (73):

The actions when hot pressing are as follows:

a. Upper mold (85) closed mold (731): The upper mold (85) device is closed with the side guide rod devices (86).

b. Into the powder (732): the magnetic powder into the filling area.

c. Upper mold pressing device (84) Pressing (733): actuating with the pressing device, applying pressure to make the powder in the powder filling zone into the cavity, and overmolding with the magnetic energy storage component (A) to be coated, due to The heating and pressing characteristics, at which time the magnetic powder appears to be softened/melted, and can be tightly coated on the surface of the magnetic energy storage element (A) to be coated.

d. Upper mold holding pressure (74): The upper mold pressing device is kept still, so that the pressing area is kept under pressure, and the molding time is not enough to cause lamination.

4. Demoulding action (75):

The action when demolding is divided as follows:

a. Upper mold opening (751): The upper mold device is opened with the guide rod devices on both sides.

b. Demoulding ejector device demoulding (752): The demoulding device is actuated upwards to allow the device to come out of the cavity with the demolding device for subsequent manual or automated retrieval.

When the magnetic powder hot pressing technology of the present invention is used, the following points should be noted:

a. Heat resistance of magnetic powder: Since all the powder pipelines in the present invention need to be heated and kept, when using magnetic raw materials, it is necessary to consider whether the heating temperature causes deterioration of magnetic conditions.

b. Heat resistance of additives (binders, lubricants): Since all the powder pipelines in the invention need to be heated and insulated, when using additives, it is necessary to consider whether the heating temperature causes high temperature oxidative decomposition, and the heating temperature does not exceed the combined use. The thermal decomposition temperature of the agent is predominant, for example polycarbonate (PC) is greater than 310 °C.

c. Design of the cavity inlet: The main influencing factors of the cavity inlet design are as follows:

1. Finished molding density: Appropriate inlet size can achieve high molding density.

2. Magnetic energy storage element (A) Abrasion resistance of the coating to be coated: The molding powder will rub the magnetic energy storage element (A) to be coated at high speed under pressure, causing internal damage to the monomer or component. Therefore, it is necessary to proceed from the inlet port angle, position, size, and magnetic energy storage component (A) to be coated.

3. Demoulding burrs: Appropriate feed opening design helps to reduce the raw edges.

The invention is further illustrated by the following examples, which are to be considered as illustrative and not restrictive.

Example:

The description is made with a surface mounted device inductor embodiment.

The device size is shown in Figure 11A. See Table 1 for details. *H size will change the following three sizes according to the experimental conditions, indicating the influence of core volume change on power consumption

X. The diameter is 0 mm, that is, the iron core is not placed.

Y. A columnar core with a diameter of 4.5 mm and a height of 4.95 mm, made of iron-aluminum-niobium alloy.

Z. The shape of the T-core is shown in Figure 11B. The material is iron-aluminum-niobium alloy.

The finished product photo side view is shown in Figure 12, the finished product front view is shown in Figure 13, and the finished product top view (with iron core (2) diameter: 4.5mm as an example) as shown in Figure 14.

Experimental conditions:

Make different sizes of iron core (2) as for the coil (coil wire diameter 1.2mm, line The inner diameter of the ring is 4.6 mm and the number of turns is 2.5 turns. After being covered by the magnetic shielding material (4), the inductance and power consumption of the device are measured.

Test Conditions:

Sensing value: frequency 500Khz, AC voltage 1 volt.

Power consumption: frequency 300Khz, AC voltage 1 volt, DC current 30 amps.

Experimental results and discussion:

It can be seen from Table 2 that by increasing the magnetic permeability of the high magnetic permeability and the low magnetic loss core, the sense value of the device can be increased and the power consumption can be reduced.

The above are only the preferred embodiments of the present invention, and are merely illustrative and not restrictive. It will be understood by those skilled in the art that many changes, modifications, and equivalents may be made within the spirit and scope of the invention as defined by the appended claims.

(1)‧‧‧ Current-carrying coil

(2)‧‧‧ magnetic core

(3) ‧ ‧ covers

(31)‧‧‧Component gap

(4)‧‧‧ Magnetic shielding materials

(71) ‧ ‧ heating

(72) ‧‧‧The object to be coated is placed in the cavity

(73) ‧ ‧ hot pressing

(731) ‧‧‧Off

(732)‧‧‧ into powder

(733)‧‧‧ Press

(74) ‧‧‧Pressure holding

(75)‧‧‧Mold release action

(751) ‧‧‧Upper mold opening

(752) ‧‧‧Release ejector

(81)‧‧‧Powder bucket

(82) ‧‧‧ material management

(83)‧‧‧Mold

(84)‧‧‧ Pressing device

(85)‧‧‧上模

(86)‧‧‧Guide device

(A) ‧‧‧Magnetic energy storage components

(B) ‧‧‧Hot-pressed magnetic components

The first figure is a cross-sectional view of a thermoformed magnetic element of the present invention.

The second figure is a cross-sectional view showing the combination of the magnetic core and the current-carrying coil of the present invention.

The third figure is a cross-sectional view showing another embodiment of the combination of the magnetic core and the current-carrying coil of the present invention.

The fourth figure is a cross-sectional view showing another embodiment of the combination of the magnetic core and the current-carrying coil of the present invention.

Fig. 5 is a cross-sectional view showing another embodiment of the combination of the magnetic core and the current-carrying coil of the present invention.

Figure 6 is a schematic diagram showing the steps of manufacturing a thermoformed magnetic component of the present invention.

Figure 7 is a diagram showing the manufacturing process of the magnetic powder hot-pressed magnetic component of the present invention.

The eighth figure is a diagram of the hot pressing device of the present invention.

The ninth drawing is a cross-sectional view of a conventional open cylindrical core element.

The tenth view is a cross-sectional view of a conventional combined core element.

An eleventh A is a dimensional view of a device according to an embodiment of the present invention.

The eleventh B is a T-shaped core diagram of an embodiment of the present invention.

Figure 12 is a side view of the finished product of the embodiment of the present invention.

Figure 13 is a front elevational view of the finished embodiment of the present invention.

Figure 14 is a plan view of a finished product of an embodiment of the present invention.

(1)‧‧‧ Current-carrying coil

(2)‧‧‧ magnetic core

(4)‧‧‧ Magnetic shielding materials

(A) ‧‧‧Magnetic energy storage components

(B) ‧‧‧Hot-pressed magnetic components

Claims (9)

A magnetic element hot press forming manufacturing method, comprising: arranging a current carrying coil (1) around a periphery of a magnetic core (2) to form a magnetic energy storage element (A), placing it in a mold and a magnetic energy storage element ( A) The magnetic shielding material (4) is externally injected, and the hot-pressed magnetic element (B) coated with the magnetic shielding material (4) is obtained through a thermoforming process; wherein the magnetic core (2) comprises a general magnetic component. a magnetic core rod coated or a composite magnetic material having a single magnetic or magnetic property with low magnetic loss (Core Loss) and good permeability; wherein the magnetic shielding material (4) comprises magnetic powder, combined a general magnetic shielding material which is mixed and stirred uniformly, or a composite magnetic material having a single or magnetic property with high electromagnetic shielding (EMI Shielding); wherein the thermoforming process refers to heating the magnetic shielding material (4) After softening and melting at 140-350 ° C, the magnetic shielding material (4) is pressed by a pressing device, so that the current-carrying coil (1) and the magnetic core (2) are encapsulated in the magnetic shielding material (4). And to achieve complex molding such as corners, hollow, and small size. The method for manufacturing a magnetic element by hot press forming according to the first aspect of the invention; wherein the magnetic powder comprises: Hogonas SC200, SC100.26 Beipiao Shenglong BF200.27, BF100.27, etc. iron powder or alloy iron powder (Fe, Al, Si, Cr, Ni, Co) or other similar magnetically conductive mixed powder (such as Sendust, Amorphous, MPP, Hi-Flux); The binder comprises: a magnetic powder powder using 4% to 20% by weight of a single or a plurality of unique resins, and as a magnetic molecular bonding agent during hot pressing, the resin type used may include polycarbonate (PC) and styrene resin. (PS), polyethylene (PE), nylon (Nylon), polypropylene (PP) and other commonly used hot pressing materials; wherein the lubricant comprises: a lubricant used according to magnetic powder 0.05% to 3% (such as white wax, disulfide Molybdenum, PTFE, etc., so that the lubrication effect during hot pressing contributes to demoulding. A magnetic element hot press forming device comprising a magnetic core (2), a current carrying coil (1) surrounding the periphery of the magnetic core (2), and a heat pressing manner on the periphery of the magnetic core (2) and the current carrying coil (1) A thermoformed magnetic component device made of a magnetic shielding material (4); wherein the magnetic core (2) comprises a magnetic core rod coated with a general magnetic component or has a low magnetic loss (Core Loss) and is good A composite magnetic material having a single magnetic property or a different magnetic property; wherein the magnetic shielding material (4) comprises a general magnetic shielding material which is uniformly mixed and stirred by magnetic powder, a binder and a lubricant or has high electromagnetic wave shielding. (EMI Shielding) A composite magnetic material with a single or different magnetic properties. The magnetic element hot press forming device according to claim 3, wherein the magnetic shielding material (4) covering the current carrying coil (1) and the magnetic core (2) can be completely packaged according to the component size. Cover or partial coating. The magnetic element hot press forming device according to claim 3, wherein the magnetic core (2) and the magnetic shielding material (4) can be adjusted in volume ratio to obtain a desired inductance value, magnetic loss and related electromagnetic characteristics. . The magnetic element hot press forming device according to claim 3, wherein the magnetic core (2) can be designed to protrude the current carrying coil (1), thereby effectively avoiding the problem of magnetic line choking, and the sensitivity is 20~ 50% improvement. The magnetic element hot press forming device according to claim 3, wherein the magnetic core (2) has a T shape, so that the surface area and the material volume ratio of the magnetic core (2) and the magnetic shielding material (4) are increased. In order to effectively avoid the loss of magnetic field lines on the junction of the magnetic core (2) and the magnetic shielding material (4) and enhance the sense of inductance. The magnetic element hot press forming apparatus according to claim 3, wherein the magnetic core (2) can increase the volume ratio, thereby increasing the sense of height and reducing the magnetic loss design. The magnetic element hot press forming apparatus according to claim 3, wherein the magnetic core (2) has a shape, a T shape, and a cylindrical shape.