Copper-iron co-fired inductor and preparation method thereof

Abstract

The invention relates to the technical field of inductors, in particular to a copper-iron co-fired inductor and a preparation method thereof. Comprising a magnetic material (1), a conductor (2) and a filling material (3), the conductor (2) is embedded in the magnetic material (1), a gap exists between the magnetic material (1) and the conductor (2), and the gap is filled with the filling material (3). Through a specific structure and a preparation method, the high-temperature stability of the inductor is effectively improved, and the inductor is adaptive to different conductor linetypes; and meanwhile, the magnetic material and the conductor can be combined, so that the adaptability of the inductor is improved, and the power supply requirement of a high-performance chip can be effectively met.

Description

Technical Field

[0001] The present invention relates to the technical field of inductors, and in particular to a copper-iron co-fired inductor and a preparation method thereof. Background Art

[0002] Inductors are a key part of electronic components, and their main function is to convert electrical energy into magnetic energy and store it. In power module design, inductors often use soft magnetic metal powder and copper coil integrated pressing technology, which has high saturation current capability and is suitable for chip energy supply. In DC power supply systems, inductors are responsible for rectification and need to operate stably at high temperatures to cope with high current conditions. With the widespread use of GPUs, inductors in power modules face higher operating temperature requirements. Traditional inductors may not be able to meet them, so the industry has developed copper-iron co-fired inductors that can operate stably under more stringent temperature conditions and support high-performance chips. However, copper-iron co-fired inductors face technical challenges such as inconsistent thermal expansion coefficients and complex co-pressing processes during the manufacturing process.

[0003] Chinese invention patent CN118486519A discloses a soft magnetic composite material and its preparation method and application. The first soft magnetic metal powder includes a spherical soft magnetic metal and a first insulating layer coated on the surface of the spherical soft magnetic metal, and the second soft magnetic metal powder includes a flaky iron-nickel alloy and a second insulating layer coated on the surface of the flaky iron-nickel alloy. This application significantly improves the density and high voltage resistance performance through the combined action of various components in the soft magnetic composite material, but it involves the dispersion problem of multiple soft magnetic metal powders, which may lead to technical problems such as uneven density distribution inside the soft magnetic material. Summary of the invention

[0004] A first aspect of the present invention provides a copper-iron co-fired inductor, comprising: a magnetic material, a conductor and a filling material, wherein the conductor is embedded in the magnetic material, a gap exists between the magnetic material and the conductor, and the filling material is filled in the gap.

[0005] The number of the conductors is 1-4, and the shape of the conductors is round or flat.

[0006] Preferably, the number of the conductors is 2-4, and the shape of the conductors is circular.

[0007] Further preferably, the diameter of the conductor is 0.1-2 mm.

[0008] The height of the conductor is higher than that of the magnetic material, and the height difference between the conductor and the magnetic material is 0.02-0.3 mm.

[0009] Preferably, the height difference between the conductor and the magnetic material is 0.05-0.2 mm.

[0010] The magnetic material includes at least one of iron silicon, iron silicon chromium, iron silicon aluminum, iron nickel, amorphous alloy, and nanocrystalline alloy.

[0011] The filling material includes epoxy resin and / or magnetic powder.

[0012] The second aspect of the present invention provides a method for preparing a copper-iron co-fired inductor, comprising the following steps: pressing a magnetic core, opening a hole in the magnetic core, and obtaining a magnetic material after sintering; embedding a conductor inside the magnetic material, and filling a filling material in the gap between the magnetic material and the conductor.

[0013] The method for preparing the copper-iron co-fired inductor also includes the following steps: pressing and sintering the magnetic core to obtain the magnetic material after opening the magnetic core; embedding the conductor inside the magnetic material, and filling the gap between the magnetic material and the conductor with filling material.

[0014] The method for preparing the copper-iron co-fired inductor also includes the following steps: pressing and sintering a magnetic core with holes to obtain a magnetic material; embedding a conductor inside the magnetic material, and filling a filling material in the gap between the magnetic material and the conductor.

[0015] The method for preparing the copper-iron co-fired inductor also includes the following steps: pressing a magnetic core with holes to obtain a magnetic material; embedding a conductor inside the magnetic material, filling a filling material in the gap between the magnetic material and the conductor, and then sintering.

[0016] The research in this application found that by pressing the magnetic material and the conductor separately, the current resistance and high temperature resistance can be improved, which may be due to improving the uniformity of the internal density distribution of the conductor and the magnetic material, and avoiding the cracking phenomenon caused by the inconsistent thermal expansion coefficients of the conductor and the magnetic material in a high temperature environment.

[0017] The pressing pressure is 12-25T / cm 2 .

[0018] Preferably, the pressing pressure is 15-20T / cm 2 .

[0019] The sintering temperature is 400-800° C., and the sintering time is 1 h-3 h.

[0020] Preferably, the sintering temperature is 500-700° C. and the sintering time is 2 h-3 h.

[0021] Beneficial Effects

[0022] 1. The conductor is embedded in the magnetic material, and there is a gap between the magnetic material and the conductor. The filling material is filled in the gap to improve the high temperature stability performance.

[0023] 2. By pressing the magnetic material and the conductor separately, the current resistance and high temperature resistance can be improved.

[0024] 3. The preparation method of the present application is simple and is suitable for different conductor line types.

[0025] 4. Magnetic materials and conductors can be combined to improve the adaptability of the inductor.

[0026] 5. The inductor prepared in this application can effectively support the power requirements of high-performance chips. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 This is a perspective view of the inductor of Example 1, wherein 1. magnetic material; 2. conductor; 3. filling material.

[0028] Figure 2 This is the magnetic material prepared in Example 1.

[0029] Figure 3 This is a three-dimensional image of the inductor prepared in Example 1.

[0030] Figure 4 This is a three-dimensional image of the inductor prepared in Comparative Example 1.

[0031] Figure 5 This is the cross-sectional density distribution diagram of the magnetic core of Example 1.

[0032] Figure 6 This is the cross-sectional density distribution diagram of the magnetic core of comparative example 1. DETAILED DESCRIPTION

[0033] Example 1

[0034] A copper-iron co-fired inductor, such as Figure 1 As shown, it includes: a magnetic material 1, a conductor 2 and a filling material 3, wherein the conductor 2 is embedded in the magnetic material 1, there is a gap between the magnetic material 1 and the conductor 2, and the filling material 3 is filled in the gap.

[0035] The number of the conductors 2 is 2, the shape of the conductors 2 is circular, and the diameter of the conductors 2 is 0.5 mm.

[0036] The height of the conductor 2 is higher than the magnetic material 1 , and the height difference between the conductor 2 and the magnetic material 1 is 0.1 mm.

[0037] The magnetic material 1 is iron silicon.

[0038] The filling material 3 is epoxy resin.

[0039] A method for preparing a copper-iron co-fired inductor comprises the following steps: pressing a magnetic core, opening a hole in the magnetic core, and sintering to obtain a magnetic material 1, such as Figure 1 As shown; the conductor 2 is embedded in the magnetic material 1, and the filling material 3 is filled in the gap between the magnetic material 1 and the conductor 2, as shown Figure 2 shown.

[0040] The pressing pressure is 20T / cm 2 The sintering temperature is 600° C. and the sintering time is 2 h.

[0041] Example 2

[0042] The specific implementation is the same as that of Example 1; the difference is that in Example 2, the preparation method of the copper-iron co-fired inductor is the following steps: pressing and sintering the magnetic core to obtain the magnetic material 1 after opening the magnetic core; embedding the conductor 2 inside the magnetic material 1, and filling the filling material 3 in the gap between the magnetic material 1 and the conductor 2.

[0043] Example 3

[0044] The specific implementation is the same as that of Example 1; the difference is that in Example 3, the preparation method of the copper-iron co-fired inductor is the following steps: pressing and sintering a perforated magnetic core to obtain a magnetic material 1; embedding a conductor 2 inside the magnetic material 1, and filling a filling material 3 in the gap between the magnetic material 1 and the conductor 2.

[0045] Example 4

[0046] The specific implementation is the same as that of Example 1; the difference is that in Example 4, the method for preparing the copper-iron co-fired inductor comprises the following steps: pressing a magnetic core with holes to obtain a magnetic material 1; embedding a conductor 2 inside the magnetic material 1, filling a filling material 3 in the gap between the magnetic material 1 and the conductor 2, and then sintering.

[0047] Comparative Example 1

[0048] The magnetic core and the copper conductor are pressed together, and the pressing pressure is 20T / cm 2 The sintering temperature is 600°C and the sintering time is 2h. Figure 3 Shown

[0049] Performance testing methods and data

[0050] The following performance tests were carried out in Example 1 and the comparative example, and the test data are listed in Table 1.

[0051] 1. Density uniformity, such as Figure 5 and Figure 6 As shown, in Example 1, the magnetic core is pressed alone, and the density distribution in the cross section of the magnetic core is uniform, while in Comparative Example 1, the magnetic core and the copper conductor are pressed together, and the density distribution inside the magnetic core is uneven.

[0052] 2. Aging performance: The inductors prepared in the examples and comparative examples were welded on a test board, a rated current was passed through the board, and then the board was placed in a high temperature box (125°C) for 500 hours. After 500 hours, the test board was taken out to observe whether the product appearance and electrical properties of the test product had changed.

[0053] The product of Comparative Example 1, in which the magnetic core and the copper conductor are pressed together, has cracks on the surface of the product during the 500-hour life test. The appearance of Examples 1-4 has no obvious change after a life of 500 hours.

Claims

1. A copper-iron co-fired inductor, characterized in that: include: A magnetic material (1), a conductor (2) and a filling material (3), wherein the conductor (2) is embedded in the magnetic material (1), a gap exists between the magnetic material (1) and the conductor (2), and the filling material (3) is filled in the gap.

2. The copper-iron co-fired inductor according to claim 1, characterized in that: The number of the conductors (2) is 1-4, and the shape of the conductors (2) is round or flat.

3. The copper-iron co-fired inductor according to claim 2, characterized in that: The height of the conductor (2) is higher than that of the magnetic material (1), and the height difference between the conductor (2) and the magnetic material (1) is 0.02-0.3 mm.

4. The copper-iron co-fired inductor according to claim 3, characterized in that: The magnetic material (1) comprises at least one of iron silicon, iron silicon chromium, iron silicon aluminum, iron nickel, amorphous alloy, and nanocrystalline alloy.

5. A method for preparing the copper-iron co-fired inductor according to any one of claims 1 to 4, characterized in that: The following steps are involved: The magnetic core is pressed, holes are opened in the magnetic core, and a magnetic material (1) is obtained after sintering; a conductor (2) is embedded in the magnetic material (1), and a filling material (3) is filled in the gap between the magnetic material (1) and the conductor (2).

6. The method for preparing the copper-iron co-fired inductor according to claim 5, characterized in that: The method comprises the following steps: pressing a magnetic core and sintering it, and obtaining a magnetic material (1) after opening a hole in the magnetic core; embedding a conductor (2) inside the magnetic material (1), and filling a filling material (3) in the gap between the magnetic material (1) and the conductor (2).

7. The method for preparing the copper-iron co-fired inductor according to claim 5, characterized in that: The following steps are involved: A magnetic core with holes is pressed and sintered to obtain a magnetic material (1); a conductor (2) is embedded in the magnetic material (1), and a filling material (3) is filled in the gap between the magnetic material (1) and the conductor (2).

8. The method for preparing the copper-iron co-fired inductor according to claim 5, characterized in that: The following steps are involved: A magnetic core with holes is pressed to obtain a magnetic material (1); a conductor (2) is embedded in the magnetic material (1), a filling material (3) is filled in the gap between the magnetic material (1) and the conductor (2), and then sintering is performed.

9. The method for preparing the copper-iron co-fired inductor according to any one of claims 6 to 8, characterized in that: The pressing pressure is 12-25T / cm 2 .

10. The method for preparing the copper-iron co-fired inductor according to claim 9, characterized in that: The sintering temperature is 400-800° C. and the sintering time is 1-3 hours.

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