CN115346789A

CN115346789A - Magnetic core and manufacturing method thereof, mold, inductance element and manufacturing method thereof

Info

Publication number: CN115346789A
Application number: CN202210966156.XA
Authority: CN
Inventors: 刘俊; 刘伟斌; 娄海飞
Original assignee: Hengdian Group DMEGC Magnetics Co Ltd
Current assignee: Hengdian Group DMEGC Magnetics Co Ltd
Priority date: 2022-08-12
Filing date: 2022-08-12
Publication date: 2022-11-15

Abstract

The present disclosure provides a magnetic core and a method of manufacturing the same, a mold, an inductance component and a method of manufacturing the same, the method of manufacturing the magnetic core including: and forming the magnetic core by performing a hot pressing process on the granulated raw materials, wherein the raw materials comprise magnetic powder and a binder, so that the strength of the manufactured magnetic core is higher.

Description

Magnetic core and manufacturing method thereof, mold, inductance element and manufacturing method thereof

Technical Field

The present disclosure relates to the field of electronic components, and in particular, to a magnetic core, a manufacturing method thereof, a mold, an inductance component, and a manufacturing method thereof.

Background

Inductive elements have many roles in the circuit such as filtering, oscillating, delaying, notching, etc. The inductance element has wide application range and more application quantity.

In the inductance component, a coil mainly plays a role, but the coil needs to be wound around a magnetic core to maintain its shape. The strength of the magnetic core influences the yield of the winding process, and then the utilization rate and the production efficiency of the whole production line can be influenced.

Disclosure of Invention

In view of this, the disclosed embodiments provide a magnetic core to solve the problem of low strength of the magnetic core.

In another aspect, the present disclosure further provides a method for manufacturing a magnetic core, so as to solve at least one of the problems of low production line utilization rate, more processes, low production efficiency, low strength of manufactured finished products, and low yield.

The disclosed embodiments provide a method of manufacturing a magnetic core, the method including: and forming the magnetic core by performing a hot pressing process on the granulated raw materials, wherein the raw materials comprise magnetic powder and a binder.

With this arrangement, the granulated raw material is subjected to the pressing process and the pressed raw material is heated, so that the magnetic core having a high strength can be obtained. Compared with the process of baking after cold pressing, the hot pressing process has the advantages of high production efficiency, more uniform density of the magnetic core and better internal structure form. The method for manufacturing the magnetic core provided by the embodiment of the disclosure can obtain the magnetic core with better quality, and the manufactured magnetic core has low damage rate in the transferring and subsequent process steps.

In some embodiments, prior to performing the hot pressing process, the method further comprises: and (3) drying the granulated raw materials.

So set up, through carrying out the preliminary treatment to the raw materials, can obtain the stoving material. According to the method for manufacturing the magnetic core, the magnetic core with high strength and good quality can be obtained through hot-pressing and drying the material.

In some embodiments, the temperature K of the drying process satisfies: k is more than or equal to 50 ℃ and less than or equal to 60 ℃.

By the arrangement, the temperature of the drying process can not cause the bonding of the binder, and is favorable for drying the raw materials more efficiently.

Illustratively, the time H of the drying process satisfies: h is more than or equal to 1.5H and less than or equal to 3H.

So set up, can guarantee that the raw materials through the granulation has obtained better stoving, can guarantee production efficiency again.

Illustratively, the time H of the drying process satisfies: h =2H.

With the adoption of the arrangement, the method for manufacturing the magnetic core provided by the embodiment of the disclosure can balance the efficiency and the quality of the magnetic core, and the method can obtain better comprehensive benefits at lower cost.

In some embodiments, the temperature S of the hot pressing process satisfies: s is more than or equal to 120 ℃ and less than or equal to 210 ℃.

With the adoption of the arrangement, the method for manufacturing the magnetic core provided by the embodiment of the disclosure can manufacture the magnetic core with higher strength, the yield of the magnetic core in the subsequent process steps is higher, and the probability of breakage is lower.

In some embodiments, the temperature S of the hot pressing process satisfies: s is more than or equal to 150 ℃ and less than or equal to 180 ℃.

With the adoption of the arrangement, the method for manufacturing the magnetic core provided by the embodiment of the disclosure can ensure the quality of the magnetic core and has better production benefit.

In some embodiments, the pressure P of the hot pressing process satisfies: 3T/cm ² ≤P≤6.5T/cm ² 。

So set up, can compress the raw materials, guarantee the intensity of magnetic core.

In some embodiments, the pressure P of the hot pressing process satisfies: p =4T/cm ² 。

So set up, can suitably compress the raw materials, make good magnetic core, can synthesize the life who guarantees the mould again.

In some embodiments, the method further comprises: coating inorganic salt on the magnetic powder; and mixing the binder with the magnetic powder including the inorganic salt, and performing a granulation process.

So set up, can obtain the raw materials through the granulation, guarantee then that the density of magnetic core is even, promote the intensity of magnetic core.

In some embodiments, the magnetic powder includes at least one of amorphous powder, alloy powder, and carboxyl iron powder; inorganic salts include phosphates; the adhesive comprises: at least one of epoxy resin, phenolic resin, organic silicon resin and inorganic binder; the mesh number of the granulated raw material is 40 to 300 meshes.

So set up, the magnetic core has better magnetic property to have better intensity, guarantee then that the inductance element who constitutes by this magnetism has better performance.

Another aspect of the embodiments of the present disclosure also provides a method of manufacturing an inductance element, the method including: forming a magnetic core by the aforementioned method of manufacturing a magnetic core; forming a coil around the core; and filling the granulated raw material into the magnetic core around which the coil is wound, and performing compression molding to form the inductance element.

With the adoption of the arrangement, the breakage rate of the magnetic core is low in the process of forming the coil, and the method for manufacturing the inductance element provided by the embodiment of the disclosure can manufacture the inductance element with good performance at a high yield.

In some embodiments, the process of press forming is a hot press process.

Therefore, the yield of manufacturing the inductance element can be improved, and the damage of the inductance element is reduced.

The embodiment of the present disclosure also provides a magnetic core formed according to the aforementioned method of manufacturing a magnetic core.

The magnetic core has high strength, good structural form, low breakage rate in subsequent processes and excellent magnetic performance.

The embodiment of the present disclosure also provides an inductance element formed according to the foregoing method for manufacturing an inductance element.

The inductance element has lower manufacturing cost and can realize inductance performance.

Yet another aspect of the disclosed embodiments also provides a mold for manufacturing a magnetic core, the mold including: an upper punch; a first heater connected to the upper punch and heating the upper punch; the first lower punch is arranged opposite to the upper punch, and the first lower punch and the upper punch can slide along the opposite direction; and a second heater connected to the first lower punch and heating the first lower punch.

According to the arrangement, the first heater and the second heater of the die can respectively heat the upper punch and the first lower punch, and the die can be used for realizing a hot pressing process to manufacture the magnetic core. The magnetic core manufactured by the die has higher strength.

In some embodiments, the die further comprises a middle die comprising a forming cavity adapted to be respectively penetrated from both sides by the upper punch and the first lower punch.

So set up, the density of the magnetic core that forms is more even, and is convenient for return the material from the centre form.

In some embodiments, the die further comprises a second lower punch slidably movable in an opposite direction to the first lower punch and sleeved to the first lower punch.

So set up, this mould can have the structure of two, can make T type magnetic core fast effectively, has better comprehensive benefit.

Drawings

FIG. 1 is a schematic flow chart diagram of a method for manufacturing a magnetic core in an embodiment of the present disclosure;

fig. 2 is a schematic flow diagram of a method for manufacturing an inductive element in an embodiment of the disclosure;

fig. 3 is a schematic structural diagram of a T-shaped magnetic core provided in an embodiment of the present disclosure;

FIG. 4 is a schematic front view of a T-core provided by an embodiment of the present disclosure;

fig. 5 is a schematic structural diagram of a T-shaped magnetic core after winding according to an embodiment of the disclosure;

fig. 6 is a schematic structural diagram of an inductance element according to an embodiment of the disclosure;

fig. 7 is a schematic front view of a mold for manufacturing a magnetic core provided by an embodiment of the present disclosure;

fig. 8 is an isometric view of a partial structure of the mold shown in fig. 7.

Reference numerals: 10. a magnetic core; 11. a center pillar; 12. a pendulum structure; 20. a coil; 100. an inductance element; 300. a mold; 310. an upper punch; 311. punching a movable plate; 3111. an upper connecting portion; 312. punching a heat insulation plate; 313. punching a heating plate; 320. a middle mold; 321. a middle mold movable plate; 322. a first guide post; 323. a second guide post; 324. a lower connecting plate; 330. a first lower punch; 331. a first lower punch fly; 332. the next stamping and heating plate; 333. punching a thermal insulation board next; 340. a second lower punch; 341. a second lower punch flap; 342. and a third guide pillar.

Detailed Description

The technical solutions in the embodiments of the present disclosure will be described clearly and completely with reference to the drawings in the embodiments of the present disclosure, and it is obvious that the embodiments described are only some embodiments of the present disclosure, rather than all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments disclosed herein without making any creative effort, shall fall within the protection scope of the present disclosure.

It will be understood that when an element is referred to as being "mounted on" another element, it can be directly on the other element or intervening elements may also be present. When a component is referred to as being "disposed on" another component, it can be directly on the other component or intervening components may also be present. When an element is referred to as being "secured to" another element, it can be directly secured to the other element or intervening elements may also be present.

The dimensions of the structures shown in the figures herein do not represent actual dimensions and may be adjusted as desired for actual production. The terms "upper", "lower", "left", "right", and the like as used herein refer to the orientation in the drawings and, unless otherwise specified, should not be construed as limiting the product of actual use.

The first, second, third, etc. are used herein only to distinguish the same features, and it is understood that the first lower punch may also be referred to herein as the second lower punch, which may also be referred to as the first lower punch.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs. The terminology used herein in the description of the disclosure is for the purpose of describing particular embodiments only and is not intended to be limiting of the disclosure. As used herein, the term "or/and" includes any and all combinations of one or more of the associated listed items.

As shown in fig. 1, an embodiment of the present disclosure provides a method 1000 of manufacturing a magnetic core, the method 1000 including step S101: the magnetic core is formed by a hot pressing process.

Specifically, the raw material may be subjected to a hot pressing process, and then the magnetic core may be formed. Illustratively, the raw materials include a magnetic powder and a binder. The raw material may be subjected to a granulation process, and then the granulated raw material may be subjected to a hot pressing process in step S101.

According to the method for manufacturing the magnetic core, the pressed raw materials are heated during the pressing process, so that the hot pressing process is realized. Compared with the process of transferring the magnetic core after the common pressing process and then baking, the strength of the magnetic core manufactured by the method provided by the embodiment of the disclosure is higher. In the step of transferring the magnetic core after the ordinary pressing process, because the strength of the unbaked magnetic core is low and the binder of the unbaked magnetic core may not be compacted, the magnetic core may be damaged in the step of transferring, so that the yield of the whole process is lost, the efficiency is low and the equipment investment is large. The method provided by the embodiment of the disclosure has the advantages of simple process and high efficiency; the temperature can be set automatically in the hot pressing process, and the yield is high when the magnetic cores are produced in batches; especially for a thin magnetic core, the method has better advantage of ensuring the strength of the thin magnetic core.

In an exemplary embodiment, as shown in fig. 1, the method 1000 of manufacturing a magnetic core further includes step S102: the drying material is formed by drying the granulated raw materials. Then step S101 may comprise: and carrying out hot pressing process on the dried material to form the magnetic core.

After the raw materials are dried, the state of the binder on the surface of the magnetic powder can be adjusted, so that the raw materials have better performance in the hot pressing process. In the process of the hot pressing process, the raw materials are pressed and molded, gaps among the magnetic powder are compacted and the binding agents are mutually bonded, and the density of the pressed raw materials is improved and the improvement is uniform.

Illustratively, the feedstock is subjected to a granulation process. Specifically, the method 1000 of manufacturing a magnetic core includes: the method comprises the steps of coating inorganic salt on the magnetic powder, mixing a binder with the magnetic powder containing the inorganic salt, and performing a granulation process.

Illustratively, the magnetic powder includes at least one of amorphous powder, alloy powder, and carboxyl iron powder. The proportion of the components of the magnetic powder can be adjusted according to the product characteristics, and the magnetic powder can be obtained by mixing the components, for example, amorphous powder and alloy powder according to a certain proportion. The magnetic powder is formed by gathering discrete dust particles.

Illustratively, the step of coating the magnetic powder with an inorganic salt includes: a weak acid such as phosphoric acid and an inorganic salt are added to form a coating layer for coating the dust particles. The material of the coating may include phosphate.

Illustratively, the binder includes: at least one of epoxy resin, phenolic resin, silicone resin and inorganic binder.

Illustratively, the step of performing the granulation process further comprises a screening step. Specifically, particles with 40-300 meshes can be screened. This mesh's raw materials through granulation is used for hot briquetting to go out the magnetic core, has better mobility for the density of magnetic core is even, the bonding state is good, reduces the local damaged probability of magnetic core, has promoted the yield of magnetic core.

In an exemplary embodiment, the temperature K of the drying process satisfies: k is more than or equal to 50 ℃ and less than or equal to 60 ℃. K is the heating temperature of the equipment used in the drying process, and is also considered as the temperature to which the raw material is heated. This temperature allows the accelerated evaporation of the water, etc., introduced by the weak acid or the binder, from the granulated material and ensures that the remaining components are not denatured. Illustratively, the temperature K of the drying process satisfies: k =50 ℃.

In an exemplary embodiment, the time H of the drying process satisfies: h is more than or equal to 1.5H and less than or equal to 3H. H is a time of the drying process, and specifically may be a time of maintaining a predetermined temperature. The time of the drying process meets the relational expression, and a good drying effect can be realized. Illustratively, the time H of the drying process satisfies: h =2H. The drying time reaches two hours, the dried material can meet the raw material requirement required by the hot pressing process, the energy consumption of the drying process is less, and the comprehensive benefit is better.

The method 1000 for manufacturing a magnetic core according to the embodiment of the present disclosure forms a magnetic core through a hot pressing process, and particularly, has a significant advantage in producing a magnetic core with a thickness of 0.8mm or less. When the magnetic core is thinner, the whole strength is lower and the magnetic core is easier to break. The magnetic core manufactured by the method 1000 provided by the embodiment of the disclosure has high strength, and has good overall yield in the production of the magnetic core with the thickness specification of 0.8mm, 0.65mm or 0.5 mm.

Illustratively, as shown in fig. 3, embodiments of the present disclosure provide a method 1000 of manufacturing a magnetic core for forming a magnetic core 10, where the magnetic core 10 is a T-core (Tcore). The magnetic core 10 includes a center pillar 11 and a pendulum structure 12. The axial direction of the center pillar 11 may be parallel to the Z-axis direction, and the radial direction of the center pillar 11 may be substantially parallel to an XY plane formed by the X-axis direction and the Y-axis direction. The pendulum structure 12 is located on one side of the center pillar 11 in the axial direction thereof, and exemplarily, a projection of the pendulum structure 12 in the Z-axis direction covers the center pillar 11. Illustratively, the pendulum structure 12 extends over the center leg 11 in at least one radial direction of the center leg 11.

Illustratively, table 1 shows the strength of the pendulum structure of the magnetic core obtained by hot press molding at different temperatures when the thickness of the pendulum structure in the Z-axis direction is 0.25mm, wherein the pressure per unit area of the hot press process is 4T/cm ² 。

Table 1: structural strength of T-shaped magnetic core pendulum

Temperature of

30℃

60℃

90℃

120℃

150℃

180℃

210℃

Strength of

0.40N

0.90N

1.30N

1.80N

1.95N

2.00N

2.15N

The pendulum structure of the T-shaped magnetic core can be measured by adopting a thrustor, and the height and the measuring position are kept consistent during each measurement. As shown in table 1, the strength of the pendulum structure of the T-shaped magnetic core formed by performing the hot pressing process at a temperature of 30 ℃ or 60 ℃ was less than 1N. Even if the hot pressing process is carried out at the temperature of 90 ℃, the strength of the pendulum structure of the formed T-shaped magnetic core is only 1.30N. With the continuous rise of the temperature of the hot pressing process, the strength of the pendulum structure of the formed T-shaped magnetic core is continuously improved. In the hot pressing process, the performance of the adhesive can be better exerted after the temperature is increased. In addition, with the rise of temperature, the thermal motion of the component substances of the raw materials is intensified, the fluidity of particles is better in the compression process, the density of the magnetic core is more uniform, and the probability of local defects is lower. The magnetic core has the advantages of good microstructure form, tight tissue connection, few gaps and firm occlusion, and the strength of the magnetic core is improved along with the temperature rise.

In more detail, it can be seen from table 1 that the increase in temperature has a weaker and weaker effect on the increase in strength of the pendulum structure. When the temperature is increased from 90 ℃ to 120 ℃, the strength of the pendulum structure is increased from 1.30N to 1.80N, namely, at the basic level of 90 ℃, the temperature of the hot pressing process is increased by 30 ℃, so that the strength of the pendulum structure in the formed magnetic core is increased by 0.60N. When the temperature is increased from 180 ℃ to 210 ℃, the strength of the pendulum structure is increased from 2.00N to 2.15N, namely, at the base level of 180 ℃, the temperature of the hot pressing process is increased by 30 ℃, but the strength of the pendulum structure in the formed magnetic core is only increased by 0.15N.

Illustratively, table 2 shows the center pillar strength of the magnetic core obtained by hot press molding at different temperatures when the thickness of the pendulum structure in the Z-axis direction is 0.25mm, wherein the hot press process has a pressure per unit area of 4T/cm ² 。

Table 2: strength of center pillar of T-shaped magnetic core

Temperature of

30℃

60℃

90℃

120℃

150℃

180℃

210℃

Strength of

2.2N

3.7N

6.2N

7.2N

7.7N

7.9N

8.1N

The center pillar of the T-shaped magnetic core can be measured by adopting a thrustmeter, and the height and the measuring position of each measurement are kept consistent. As shown in table 2, the strength of the middle pillar of the T-shaped magnetic core formed by the hot pressing process at a temperature of 30 ℃ or 60 ℃ was less than 4N. Even if the hot pressing process is performed at a temperature of 90 c, the strength of the middle column of the formed T-shaped magnetic core is only 6.2N. With the continuous rise of the temperature of the hot pressing process, the strength of the formed middle column of the T-shaped magnetic core is continuously improved.

The temperature has a similar effect on the strength of the centering column and the pendulum structure. In more detail, it can be seen from table 2 that the increase in temperature has a weaker and weaker effect on the improvement of the strength of the center pillar. When the temperature is increased from 90 ℃ to 120 ℃, the strength of the middle column is increased from 6.2N to 72N, namely, at the base level of 90 ℃, the temperature of the hot pressing process is increased by 30 ℃, so that the strength of the middle column of the formed magnetic core is increased by 1.0N. When the temperature is increased from 180 ℃ to 210 ℃, the strength of the middle column is increased from 7.9N to 8.1N, namely, at the basic level of 180 ℃, the temperature of the hot pressing process is increased by 30 ℃, but the strength of the middle column of the formed magnetic core is only increased by 0.2N.

Referring to fig. 3, the structural integrity of the magnetic core 10 is primarily determined by the strength of the pendulum structure 12 and the strength of the center leg 11. The magnetic core 10 provided by the embodiment of the disclosure can better maintain the structure of the magnetic core during the transportation process, and cannot be broken as an unbaked magnetic core formed by a cold pressing process. In addition, as the strength of the entire magnetic core 10 is increased, the density of the magnetic core 10 is also increased.

Illustratively, table 3 shows the yield of the magnetic core obtained by hot press molding at different temperatures in the subsequent winding process when the thickness of the pendulum structure along the Z-axis direction is 0.25mm, wherein the unit area pressure of the hot press process is 4T/cm ² 。

Table 3: yield of T-shaped magnetic core

Temperature of

30℃

60℃

90℃

120℃

150℃

180℃

210℃

Yield of

1.0％

45.0％

73.0％

96.0％

98.0％

98.5％

99.0％

As shown in table 3, the yield of the formed T-shaped magnetic core in the winding process was less than 50.0% when the hot pressing process was performed at 30 ℃ or 60 ℃. When the temperature of the hot pressing process is below 60 ℃, the strength of the pendulum structure of the formed T-shaped magnetic core is less than 0.90N, and the strength of the middle column is less than 3.7N. Such a T-shaped magnetic core may have a low yield rate in short because the center pillar and the pendulum structure may be damaged in the winding process. Even if the hot-pressing process is performed at a temperature of 90 ℃, the yield of the formed T-shaped magnetic core in the subsequent winding process reaches 73.0 percent, and the yield is at least half. With the continuous rise of the temperature of the hot pressing process, the yield of the formed T-shaped magnetic core in the winding process is continuously improved.

In more detail, it can be seen from table 3 that the increase in temperature is less and less effective in increasing yield. When the temperature is increased from 90 ℃ to 120 ℃, the yield is increased from 73.0 percent to 96.0 percent, namely, the temperature of the hot pressing process is increased by 30 percent at the basic level of 90 ℃, so that the yield of the formed magnetic core in the winding process is increased by 23.0 percent. When the temperature is increased from 180 ℃ to 210 ℃, the yield is increased from 98.5% to 99.0%, namely, at the base level of 180 ℃, the temperature of the hot pressing process is increased by 30 ℃, but the yield of the formed magnetic core in the winding process is only increased by 0.5%. In addition, when the temperature of the hot pressing process is 120 ℃, the yield of the formed magnetic core in the winding process reaches 96.0% in terms of absolute value.

By summarizing the data of tables 1 to 3, exemplary, the method 1000 for manufacturing a magnetic core provided by the embodiment of the present disclosure satisfies the temperature S of the hot pressing process: s is more than or equal to 120 ℃ and less than or equal to 210 ℃. The hot pressing process within the temperature range can manufacture the magnetic core with good comprehensive strength, and the yield of the magnetic core in the subsequent winding process is higher.

Illustratively, the temperature S of the hot pressing process in the method 1000 of manufacturing the magnetic core satisfies: s is more than or equal to 150 ℃ and less than or equal to 180 ℃. The temperature of the hot pressing process is within the range of 150 ℃ to 180 ℃, so that the method can be used for forming a magnetic core with enough excellent performance, has good comprehensive benefits and low comprehensive cost of the magnetic core, and can reduce the consumption of energy.

In an exemplary embodiment, the pressure P of the hot pressing process in the method 1000 of manufacturing the magnetic core satisfies: 3T/cm ² ≤P≤6.5T/cm ² . Sufficient pressure is applied to the raw materials, so that the strength of the magnetic core can be ensured, and the service life of the die can be prevented from being excessively shortened. Illustratively, the pressure P of the hot pressing process satisfies: p =4T/cm ² . The pressure of approximately this value can comprehensively take into account the die life and the compression characteristics of the raw material in the hot pressing process, and the method 1000 can efficiently and continuously manufacture a magnetic core with excellent performance.

Embodiments of the present disclosure provide, in another aspect, a magnetic core manufactured according to the aforementioned method of manufacturing a magnetic core. Illustratively, the method 1000 for manufacturing the magnetic core provided by the embodiment of the disclosure is suitable for manufacturing the T-shaped magnetic core with the thickness of the pendulum structure being 0.25mm, 0.20mm and 0.16 mm. T-shaped magnetic cores manufactured by a general pressing process post-baking method are comparative examples, and data differences between the embodiments of the present disclosure and the comparative examples are shown in tables 4 to 6.

Specifically, for a T-shaped core having a pendulum structure with a thickness of 0.25mm, table 4 shows data for the core of the comparative example, and the method provided by the examples of the present disclosure in which the temperature is 180 ℃ and the pressure is 4T/cm ² Data of the formed magnetic core:

table 4: data of T-shaped magnetic core with pendulum thickness of 0.25mm

	Center pillar strength	Strength of pendulum structure	Yield of winding process
				Comparative example	7.8N	1.95N	98.4％
Examples	7.9N	2.00N	98.5％

Specifically, for a T-shaped core having a pendulum structure with a thickness of 0.20mm, table 5 shows data of the core of the comparative example, and the method provided in the embodiment of the present disclosure in which the temperature is 180 ℃ and the pressure is highForce of 4T/cm ² Data of the formed magnetic core:

table 5: data of T-shaped magnetic core with thickness of 0.20mm pendulum

	Center pillar strength	Strength of pendulum structure	Yield of winding process
				Comparative example	5.1N	1.40N	70％
Examples	7.9N	1.90N	98.1％

Specifically, for a T-shaped core having a pendulum structure with a thickness of 0.16mm, table 6 shows data of the core of the comparative example, and the method provided in the examples of the present disclosure in which the temperature is 180 ℃ and the pressure is 4T/cm ² Data of magnetic core formed:

table 6: data of T-shaped magnetic core with pendulum thickness of 0.16mm

	Center pillar strength	Strength of pendulum structure	Yield of winding process
				Comparative example	3.7N	1.10N	58％
Examples	6.7N	1.76N	97.6％

From tables 4 to 6, for the T-shaped magnetic core having the pendulum structure with a thickness of not more than 0.25mm, the performance of the magnetic core manufactured by the comparative example is reduced rapidly, and the yield loss is high. For example, for a T-shaped magnetic core having a pendulum structure with a thickness of 0.25mm, the center leg strength of the magnetic core manufactured by the comparative example may still be 7.8N, whereas when the pendulum thickness of the T-shaped magnetic core to be formed is decreased to 0.16mm, the center leg strength of the magnetic core manufactured by the comparative example has been abruptly decreased to 3.7N, and simultaneously, the yield in the winding process has been decreased to 58%.

The magnetic core of the embodiment of the disclosure has a high yield under various specifications, and even for a T-shaped magnetic core with a pendulum structure as thin as 0.16mm, the magnetic core of the embodiment of the disclosure can still have a yield of 97.6%. Roughly, this disclosed embodiment provides a magnetic core, the ratio of center pillar intensity and pendulum structure thickness is greater than 31.6, and the ratio of pendulum structure intensity and pendulum structure thickness is greater than 8. As for the magnetic core of the comparative example, the ratio of the column strength to the thickness of the pendulum structure was less than 31.2, and the ratio of the strength of the pendulum structure to the thickness of the pendulum structure was less than 7.8.

The magnetic core provided by the embodiment of the disclosure has higher structural strength, and especially, the thin magnetic core has high yield.

As shown in fig. 2, embodiments of the present disclosure provide a method 2000 of manufacturing an inductive element, which method 2000 may include the following steps.

Step S101, a magnetic core is formed. Specifically, the magnetic core may be formed through a hot pressing process. Step S101 may be a step of the aforementioned method 1000 of manufacturing a magnetic core. That is, method 2000 of manufacturing an inductive element may include the step of forming a magnetic core by the aforementioned method 1000 of manufacturing a magnetic core.

In step S201, a coil is formed around a core.

And S202, filling the granulated raw material into the magnetic core around which the coil is wound, and performing compression molding to form the inductance element.

According to the method for manufacturing the inductance element, the structural strength of the magnetic core is high, so that the yield is high in the step of forming the coil, and the inductance element with excellent performance can be further formed. The method has the advantages of low comprehensive cost, simple process steps and high utilization rate.

Referring to fig. 3 and 4, in a method 2000 of manufacturing an inductance component according to an embodiment of the disclosure, a magnetic core 10 may be formed in step S101, and the magnetic core 10 may be a T-shaped magnetic core. The magnetic core 10 includes a center pillar 11 and a pendulum structure 12. The center leg 11 is used to be wound by a wire in a winding process.

Exemplarily, step S202 includes: through a winding process, a coil is formed. As shown in fig. 5, coil 20 is wound around center post 11 and may abut pendulum structure 12. The wire of the coil 20 may have an insulating layer and both ends of the coil 20 may extend away from the spine 11.

In an exemplary embodiment, the process of press forming in step S203 is a hot press process. As shown in fig. 6, the inductance element 100 is obtained after step S203. Illustratively, the inductance component 100 also needs to be formed with a positive electrode and a negative electrode (not shown), which are electrically connected to both ends of the coil 20, respectively.

Another aspect of the embodiments of the present disclosure provides an inductance element formed by the foregoing method of manufacturing an inductance element. The inductance element has good performance and low comprehensive cost.

As shown in fig. 7 and 8, the present disclosure provides a mold 300 for manufacturing a magnetic core, the mold 300 including: an upper punch 310, a first lower punch 330, a first heater, and a second heater.

As shown in fig. 8, the upper punch 310 and the first lower punch 330 are disposed opposite to each other, and when they are relatively close to each other, the raw material therebetween is press-formed into a magnetic core.

Illustratively, the first heater includes an upper punch heating plate 313 and an upper punch heat insulating plate 312. The upper punch plate 313 is heat-transferably connected to the upper punch 310, and serves to perform a function of heating the upper punch 310 by the first heater. The upper punch heating plate 313 is connected to other components of the die 300, such as the upper punch moving plate 311, through the upper punch heat insulating plate 312. The upper heat insulation plate 312 serves to thermally connect the upper heating plate 313 to the upper punch plate 311, preventing heat of the upper heating plate 313 from being transferred to the upper punch plate 311, to improve the working efficiency of the upper heating plate 313. Illustratively, the upper punch heating plate 313 includes a plate body and a heating rod inserted in the plate body.

Exemplarily, the second heater may include a next die heating plate 332 and a next die insulation plate 333. The lower punch plate 332 is heat-transferably connected to the first lower punch 330, and serves to accomplish the function of the second heater to heat the first lower punch 330. The next punch heating plate 332 may be connected to other parts of the die 300, such as the first lower punch moving plate 331, through the next punch insulating plate 333.

The die provided by the embodiment of the disclosure can be used for forming the magnetic core, and the die is provided with the first heater and the second heater, so that the upper punch and the first lower punch can be heated, and then the pressed raw material can be heated during working. The die can realize a hot-pressing process, and a magnetic core with good overall strength and high yield is formed.

Illustratively, the mold 300 further includes an intermediate mold 320. As shown in fig. 8, the upper punch 310 and the first lower punch 330 are adapted to extend into the molding cavities (not shown) of the intermediate mold 320 from both sides of the intermediate mold 320, respectively. In use of the die 300, the granulated raw material may be filled into the molding cavity of the middle mold 320, and then the magnetic core may be formed by hot-pressing a corresponding one portion of the raw material through the upper punch 310 and the first lower punch 330.

As shown in fig. 7, the upper punch plate 311 is slidably connected to the first guide post 322, and the upper connecting portion 3111 is used for connecting a driving device (not shown).

The first guide post 322 is fixedly connected to the middle mold moving plate 321 to which the middle mold 320 is fixedly connected, and the second guide post 323 is also fixedly connected to the middle mold moving plate 321. The second guide post 323 penetrates through the first lower punch movable plate 331 and is slidably connected to the first lower punch movable plate 331, and the second guide post 323 is slidably connected to the lower connecting plate 324. The intermediate mold 320 may slide relative to the first lower punch 330 to facilitate material return.

In the exemplary embodiment, die 300 also includes a second lower punch 340. The second lower punch 340 may be sleeved on the first lower punch 330 for forming a T-shaped magnetic core. The second lower punch 340 may be fixed to the second lower punch plate 341, and the third guide pillar 342 is also fixed to the second lower punch plate 341. The third guide pillar 342 penetrates the first lower punch-moving plate 331 and is slidably connected with the first lower punch-moving plate 331, so that the second lower punch 340 and the first lower punch 330 are slidable. In addition, the lower portion of the third guide post 342 is slidably connected to the lower connection plate 324.

The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

Various forms of the flows described above may be used, and steps may be reordered, added, or deleted. The steps described in the embodiments of the present disclosure may be executed in parallel, sequentially, or in different orders, and are not limited herein as long as the desired results of the technical solutions provided in the embodiments of the present disclosure can be achieved.

The above-described embodiments are merely illustrative of several embodiments of the present disclosure, which are described in more detail and detailed, but are not to be construed as limiting the scope of the disclosure. It should be noted that, for those skilled in the art, various changes and modifications can be made without departing from the concept of the present disclosure, and these changes and modifications are all within the scope of the present disclosure. Therefore, the protection scope of the present disclosure should be subject to the appended claims.

Claims

1. A method of manufacturing a magnetic core, comprising: and forming the magnetic core by performing a hot pressing process on the granulated raw materials, wherein the raw materials comprise magnetic powder and a binder.

2. The method of manufacturing a magnetic core according to claim 1, wherein prior to performing the hot pressing process, the method further comprises: and (4) drying the granulated raw materials.

3. The method of manufacturing a magnetic core according to claim 2, wherein the temperature K of the baking process satisfies: k is more than or equal to 50 ℃ and less than or equal to 60 ℃; the time H of the drying process satisfies the following condition: h is more than or equal to 1.5H and less than or equal to 3H.

4. The method of manufacturing a magnetic core according to claim 1, wherein the temperature S of the hot pressing process satisfies: s is more than or equal to 120 ℃ and less than or equal to 210 ℃.

5. The method of manufacturing a magnetic core according to claim 4, wherein the temperature S of the hot pressing process satisfies: s is more than or equal to 150 ℃ and less than or equal to 180 ℃.

6. The method of manufacturing a magnetic core according to claim 1, wherein the pressure P of the hot pressing process satisfies: 3T/cm ² ≤P≤6.5T/cm ² 。

7. The method of manufacturing a magnetic core according to claim 6, wherein the pressure P of the hot pressing process satisfies: p =4T/cm ² 。

8. The method of manufacturing a magnetic core according to claim 1, further comprising:

coating inorganic salt on the magnetic powder; and

mixing a binder with the magnetic powder including the inorganic salt, and performing a granulation process.

9. The method of manufacturing a magnetic core according to claim 8, wherein the magnetic powder includes at least one of amorphous powder, alloy powder, and carboxyl iron powder; the inorganic salt comprises a phosphate salt; the adhesive comprises: at least one of epoxy resin, phenolic resin, organic silicon resin and inorganic binder; the mesh number of the granulated raw material is 40-300 meshes.

10. A method of manufacturing an inductive component, comprising:

forming a magnetic core by the method for manufacturing a magnetic core according to any one of claims 1 to 9;

forming a coil around the magnetic core; and

the granulated material is filled in a magnetic core around which the coil is wound, and is subjected to press molding to form an inductance component.

11. The method of manufacturing an inductance component according to claim 10, wherein the process of press forming is a hot press process.

12. Magnetic core, characterized in that it is formed according to the method of manufacturing a magnetic core of any of claims 1 to 9.

13. Inductive element, characterized in that it is formed according to the method of manufacturing an inductive element of claim 10 or 11.

14. A mold for manufacturing a magnetic core, comprising:

an upper punch;

a first heater connected to the upper punch and heating the upper punch;

a first lower punch provided opposite to the upper punch and slidable in the opposite direction; and

and a second heater connected to the first lower punch and heating the first lower punch.

15. The mold for manufacturing a magnetic core according to claim 14, further comprising an intermediate mold including a molding cavity adapted to be respectively entered from both sides by the upper punch and the first lower punch.

16. The die for manufacturing a magnetic core according to claim 14, further comprising a second lower punch slidable in the opposite direction to the first lower punch and fitted over the first lower punch.