Inductors and their fabrication methods

Abstract

The present invention provides an inductor comprising an alloy magnet and a coil, wherein the alloy magnet comprises Fe. 100‑a‑b‑c‑x‑y‑z Si a B b C c Mn x Cr y X Z In the formula, X is any one of P, Cu, Mo, and Ni, where 8≤a≤15, 6≤b≤12, 0.2≤c≤3.0, 0.1≤x≤3.5, 0.5≤y≤2.5, and 0≤Z≤4.0. The inductor of the present invention has the characteristics of low loss, high saturation magnetic induction intensity and high DC bias capability through the design and optimization of alloy composition.

Description

Technical Field

[0001] This invention relates to the field of soft magnetic alloy metallurgy technology, specifically to an inductor and its preparation method. Background Technology

[0002] Amorphous materials possess high saturation magnetic induction, high permeability, low coercivity and low high-frequency loss, good strength, wear resistance and corrosion resistance, and good temperature and environmental stability. Their excellent comprehensive performance allows them to replace permalloy, silicon steel and ferrite in power electronics technology, showing characteristics such as small size, high efficiency and energy saving. Among all soft magnetic metallic materials, they have the best performance-price ratio.

[0003] In the existing technology, carbonyl iron powder and iron-silicon-chromium powder are mainly used as raw materials for the preparation of integrally molded inductors. However, the above two powders have greater hysteresis loss and the low resistivity of the powder body results in greater eddy current loss during product application. Such products have high losses in application, causing problems such as product heating and reduced energy efficiency. Summary of the Invention

[0004] The purpose of this invention is to provide an inductor and its manufacturing method to overcome the shortcomings of the prior art.

[0005] An inductor comprising an alloy magnet and a coil, wherein the alloy composition of the alloy magnet includes Fe. 100-a-b-c-x-y-z Si a B b C c Mn x Cr y X Z In the formula, X is any one of P, Cu, Mo, and Ni, where 8≤a≤15, 6≤b≤12, 0.2≤c≤3.0, 0.1≤x≤3.5, 0.5≤y≤2.5, and 0≤Z≤4.0.

[0006] Furthermore, where 6≤b≤9 and 0.3≤y≤2.5.

[0007] Specifically, the alloy magnet's composition includes Fe. 75 Si 11 B9C 2.5 Cr 2.3 Mn 0.2 .

[0008] Furthermore, the alloy magnet comprises Fe. 74.8 Si 11 B9C 1.5 Cr 2.5 Mn 0.2 P1 or Fe 74.8 Si 11B9C 0.5 Cr 1.5 Mn 0.2 P2 or Fe 73.8 Si 11 B9C 1.5 Cr 1.5 Mn 0.2 P2 or Fe 79 Si 11 B7C 0.5 Cr 0.3 Mn 0.2 P2 or Fe 79 Si9B 6.2 C 0.5 Cr 0.3 Mn1P4.

[0009] Furthermore, the alloy magnet comprises Fe. 74.8 Si 11 B9C 1.5 Cr 2.5 Mn 0.2 Mo1 or Fe 76.8 Si 11 B9C 0.5 Cr 1.5 Mn 0.2 Mo1 or Fe 73.8 Si 11 B9C 1.5 Cr 1.5 Mn 1.2 Mo1 or Fe 78 Si 11 B7C 0.5 Cr 0.5 Mn1Mo2.

[0010] Furthermore, the alloy magnet comprises Fe. 74.8 Si 11 B9C 1.5 Cr 2.5 Mn 0.2 Ni1 or Fe 74.8 Si 11 B9C 0.5 Cr 1.5 Mn 0.2 Ni2 or Fe 74.8 Si 11 B7C 1.5 Cr 1.5 Mn 0.2 Ni3 or Fe 76.8 Si 11 B7C 0.5 Cr 0.5 Mn 0.2 Ni4.

[0011] The method for fabricating an inductor includes the following steps:

[0012] S1. The raw materials are blended and smelted according to the above-mentioned molecular formula to prepare a master alloy;

[0013] S2. The obtained master alloy is prepared into powder by means of belt crushing and powder preparation or atomization powder preparation to obtain amorphous nanocrystalline powder.

[0014] S3. The obtained amorphous nanocrystalline powder is subjected to insulating coating treatment to obtain coated powder;

[0015] S4. The obtained coated powder is subjected to molding treatment to obtain amorphous nanocrystalline insulating finished powder.

[0016] S5. The obtained amorphous nanocrystalline insulating powder is pressed into shape and baked to cure, so as to obtain an inductor.

[0017] Furthermore, in step S1, the preparation method of the master alloy is as follows:

[0018] S1-1. Based on the preset composition formula, select metal raw materials with corresponding elemental components and place them into the smelting furnace for smelting.

[0019] S1-2. After the above-mentioned metal raw materials are smelted to complete melting, alloy raw materials or non-metallic raw materials with corresponding elemental compositions are selected for secondary smelting.

[0020] S1-3. After the above materials have been completely melted in the secondary smelting, the resulting alloy melt is poured into a mold and then cooled and shaped to obtain an amorphous nanocrystalline master alloy.

[0021] Furthermore, in step S3, the insulation coating process includes the following steps:

[0022] S3-1. Mix the obtained amorphous nanocrystalline powder with nitric acid solution and acetone solution. Place the mixture in a sealed container and heat it in a water bath at a constant temperature and keep it warm.

[0023] S3-2. After the mixture has reacted fully, open the sealed container to allow the acetone to evaporate and obtain the coated powder.

[0024] Furthermore, in step S3, before the obtained amorphous nanocrystalline powder is subjected to insulating coating treatment, iron-silicon-chromium and / or carbonyl iron powder is added and thoroughly stirred and mixed to fill the gaps between the amorphous nanocrystalline powder.

[0025] Furthermore, between steps S3 and S4, the following steps are also included:

[0026] S3-1. The obtained coated powder is subjected to pre-annealing treatment to promote its insulation passivation reaction; the annealing temperature range of the pre-annealing treatment is Tx-100 to Tx+80 degrees Celsius, where Tx is the crystallization temperature of amorphous nanocrystals.

[0027] The beneficial effects of this invention are as follows:

[0028] The inductor of the present invention has the characteristics of low loss, high saturation magnetic induction intensity and high DC bias capability through the design and optimization of alloy composition. Detailed Implementation

[0029] To make the technical solution, objectives, and advantages of the present invention clearer, the following embodiments are provided to further explain and illustrate the present invention.

[0030] The inductor fabrication method of this invention specifically involves the following steps:

[0031] S1. The raw materials are blended and smelted according to the preset composition formula to prepare the master alloy;

[0032] S2. The obtained master alloy is powdered using conventional methods of strip crushing and powder preparation or atomization powder preparation in the prior art to prepare amorphous nanocrystalline powder. The powder obtained by the strip crushing and powder preparation method will be irregularly shaped; the powder obtained by the atomization powder preparation method will be spherical.

[0033] S3. The obtained amorphous nanocrystalline powder is subjected to insulating coating treatment to obtain coated powder;

[0034] S4. The obtained coated powder is subjected to molding treatment to obtain amorphous nanocrystalline insulating finished powder.

[0035] The molding process includes adding a binder to the coating powder for a secondary coating process to obtain a semi-finished powder; then, adding a lubricant to the semi-finished powder and stirring and mixing it to obtain an insulating finished powder.

[0036] S5. The obtained insulating powder is pressed into shape and baked to cure, and then further processed to obtain the inductor.

[0037] Example 1:

[0038] In the application based on step S1, the pre-defined composition formula of this invention includes Fe as the alloy component used for preparation. 100-a-b-c-x-y-z Si a B b C c Mn x Cr y X ZIn the formula, X is any one of P, Cu, Mo, and Ni, where 8≤a≤15, 6≤b≤12, 0.2≤c≤3.0, 0.1≤x≤3.5, 0.5≤y≤2.5, and 0≤z≤4.0. Preferably, 6≤b≤9 and 0.3≤y≤2.5.

[0039] The alloy composition of this master alloy will enable the powders subsequently prepared to have high amorphous forming ability, strong corrosion resistance, high saturation magnetic induction intensity, and low coercivity, and its application will have good prospects.

[0040] The preferred alloy composition scheme described above is Fe. 74.8 Si 11 B9C 1.5 Cr 2.5 Mn 0.2 P1 or Fe 74.8 Si 11 B9C 0.5 Cr 1.5 Mn 0.2 P2 or Fe 73.8 Si 11 B9C 1.5 Cr 1.5 Mn 0.2 P2 or Fe 79 Si 11 B7C 0.5 Cr 0.3 Mn 0.2 P2 or Fe 79 Si9B 6.2 C 0.5 Cr 0.3 Mn1P4.

[0041] Specifically, the smelting process of this master alloy is as follows:

[0042] S1-1. Select industrial pure iron, ductile iron, electrolytic chromium, metallic manganese and other metal raw materials, put them into a smelting furnace for smelting, the smelting temperature is 1350 to 1550 degrees Celsius, and the smelting time is 1.5 to 3.5 hours.

[0043] S1-2. After the above materials are smelted to complete melting, alloy raw materials such as ferroboron, ferrophosphorus and industrial silicon and non-metallic raw materials are added in sequence for secondary smelting.

[0044] S1-3. After the above materials have been completely melted in the second smelting, keep them at the temperature for 10 minutes.

[0045] S1-4. After the molten metal is cooled to 1350 degrees Celsius, the smelting furnace is turned on and the surface impurities of the alloy melt are removed.

[0046] S1-5. The alloy melt after removing surface impurities is poured into a steel ingot mold and then cooled and shaped to obtain the master alloy.

[0047] The preferred smelting furnace is a vacuum smelting furnace with a loading capacity of 15-35 kg.

[0048] In applications based on step S2, the master alloy with a specific alloy composition can be used to prepare corresponding amorphous nanocrystalline ribbon products, sheet-like amorphous nanocrystalline broken powder products, and spherical amorphous nanocrystalline atomized powder products.

[0049] As shown in Appendix 1, the strip made from this master alloy will have the following performance characteristics.

[0050] Appendix Table 1 (Test Performance of Amorphous and Nanocrystalline Ribbons with Different Compositions)

[0051]

[0052]

[0053] As shown in Appendix Table 2, the magnetic powder cores made from strips of this master alloy, when crushed into powder and prepared using existing magnetic powder core preparation methods, will have the following performance characteristics.

[0054] Appendix Table 2 (Test Performance of Magnetic Powder Cores Prepared from Amorphous and Nanocrystalline Powders of Different Compositions)

[0055] As shown in Appendix 3, based on existing technologies, gas atomization, water atomization, or combined water-gas atomization methods, with the master alloy...

[0056] The performance of the atomized powder will be evaluated by ring pressing, and the evaluation results will have the following performance characteristics.

[0057] Appendix Table 3 (Comparison of Ring Compression Test Performance between Amorphous and Nanocrystalline Atomized Powder and Conventional Powder)

[0058]

[0059] As shown in Appendix Table 4, based on the application of this alloy composition, the atomized powders prepared with different compositions will have the following performance characteristics in their performance evaluation results.

[0060] Appendix Table 4 (Comparison of Ring Compression Test Performance of Amorphous and Nanocrystalline Atomized Powders with Different Compositions)

[0061]

[0062]

[0063] Example 2:

[0064] The difference between this embodiment and Embodiment 1 above is that the preferred alloy composition is Fe. 74.8 Si 11 B9C 1.5 Cr 2.5 Mn 0.2 Mo1 or Fe 76.8 Si 11 B9C 0.5 Cr 1.5 Mn 0.2 Mo1 or Fe 73.8 Si 11 B9C 1.5 Cr 1.5 Mn 1.2 Mo1 or Fe 78 Si 11 B7C 0.5 Cr 0.5 Mn1Mo2.

[0065] Specifically, the smelting process of this master alloy is as follows:

[0066] S1-1. Select industrial pure iron, ductile iron, and metal raw materials such as electrolytic chromium, metallic manganese, and electrolytic molybdenum, and put them into a smelting furnace for smelting. The smelting temperature is 1350-1550 degrees Celsius, and the smelting time is 1.5-3.5 hours.

[0067] S1-2. After the above materials are smelted to complete melting, ferroboron and industrial silicon alloy raw materials and non-metallic raw materials are added in sequence for secondary smelting.

[0068] S1-3. After the above materials have been completely melted in the second smelting, keep them at the temperature for 10 minutes.

[0069] S1-4. After the molten metal is cooled to 1350 degrees Celsius, the smelting furnace is turned on and the surface impurities of the alloy melt are removed.

[0070] S1-5. The alloy melt after removing surface impurities is poured into a steel ingot mold and then cooled and shaped to obtain the master alloy.

[0071] The preferred smelting furnace is a vacuum smelting furnace with a loading capacity of 15-35 kg.

[0072] In applications based on step S2, the master alloy with a specific alloy composition can be used to prepare corresponding amorphous nanocrystalline ribbon products, sheet-like amorphous nanocrystalline broken powder products, and spherical amorphous nanocrystalline atomized powder products.

[0073] As shown in Appendix Table 5, the strip made from this master alloy will have the following performance characteristics.

[0074] Appendix 5 (Test Performance of Amorphous and Nanocrystalline Ribbons with Different Compositions)

[0075]

[0076] As shown in Appendix Table 6, the magnetic powder cores made from strips of this master alloy, when crushed into powder and prepared using existing magnetic powder core preparation methods, will have the following performance characteristics.

[0077]

[0078]

[0079] Appendix Table 6 (Test Performance of Magnetic Powder Cores Prepared from Amorphous and Nanocrystalline Powders of Different Compositions)

[0080] As shown in Appendix 7, the performance of the atomized powder made from the master alloy using the existing gas atomization, water atomization, or water-gas atomization combined method will be evaluated by ring pressing. The performance evaluation results will have the following performance characteristics.

[0081] Appendix Table 7 (Comparison of Ring Compression Test Performance between Amorphous and Nanocrystalline Atomized Powder and Conventional Powder)

[0082]

[0083] As shown in Appendix Table 8, based on the application of this alloy composition, the atomized powders made from different compositions, when evaluated according to the integral molding inductance evaluation method, will have the following performance characteristics.

[0084] Appendix Table 8 (Performance Comparison of Amorphous and Nanocrystalline Atomized Powders with Different Compositions Based on Integrated Inductance Evaluation Method)

[0085]

[0086] Example 3:

[0087] The difference between this embodiment and Embodiment 1 above is that the preferred alloy composition is: Fe 74.8 Si 11 B9C 1.5 Cr 2.5 Mn 0.2 Ni1 or Fe 75.8 Si 11 B9C 0.5 Cr 1.5 Mn 0.2 Ni2 or Fe 75.8 Si 11 B7C 1.5 Cr 1.5 Mn0.2 Ni3 or Fe 76.8 Si 11 B7C 0.5 Cr 0.5 Mn 0.2 Ni4.

[0088] Specifically, the smelting process of this master alloy is as follows:

[0089] S1-1. Select industrial pure iron, ductile iron, and electrolytic chromium, metallic manganese, electrolytic nickel and other metal raw materials, put them into a smelting furnace for smelting, the smelting temperature is 1350 to 1550 degrees Celsius, and the smelting time is 1.5 to 3.5 hours.

[0090] S1-2. After the above materials are smelted to complete melting, ferroboron and industrial silicon alloy raw materials and non-metallic raw materials are added in sequence for secondary smelting.

[0091] S1-3. After the above materials have been completely melted in the second smelting, keep them at the temperature for 10 minutes.

[0092] S1-4. After the molten metal is cooled to 1350 degrees Celsius, the smelting furnace is turned on and the surface impurities of the alloy melt are removed.

[0093] S1-5. The alloy melt after removing surface impurities is poured into a steel ingot mold and then cooled and shaped to obtain the master alloy.

[0094] The preferred smelting furnace is a vacuum smelting furnace with a loading capacity of 15-35 kg.

[0095] In applications based on step S2, the master alloy with a specific alloy composition can be used to prepare corresponding amorphous nanocrystalline ribbon products, sheet-like amorphous nanocrystalline broken powder products, and spherical amorphous nanocrystalline atomized powder products.

[0096] As shown in Appendix Table 9, the strip made from this master alloy will have the following performance characteristics.

[0097] Appendix Table 9 (Test Performance of Amorphous and Nanocrystalline Ribbons with Different Compositions)

[0098]

[0099] As shown in Appendix Table 10, the magnetic powder cores made from strips of this master alloy, when crushed into powder and prepared using existing magnetic powder core preparation methods, will have the following performance characteristics.

[0100]

[0101]

[0102] Appendix Table 10 (Test Performance of Magnetic Powder Cores Prepared from Amorphous and Nanocrystalline Powders of Different Compositions)

[0103] As shown in Appendix Table 11, the performance of the atomized powder made from the master alloy using the existing gas atomization, water atomization, or water-gas atomization combined method will be evaluated by ring pressing. The performance evaluation results will have the following performance characteristics.

[0104] Appendix Table 11 (Comparison of Ring Compression Test Performance between Amorphous and Nanocrystalline Atomized Powder and Conventional Powder)

[0105]

[0106] As shown in Appendix Table 12, based on the application of this alloy composition, the atomized powders made from different components, when evaluated according to the integral molding inductance evaluation method, will have the following performance characteristics.

[0107] Appendix Table 12 (Performance Comparison of Amorphous and Nanocrystalline Atomized Powders with Different Compositions Based on Integrated Inductance Evaluation Method)

[0108]

[0109] Example 4:

[0110] Based on the applications described in Examples 1 to 3 above, in order to optimize the powder flowability and bulk density, the atomized powder prepared in step S2 can be dried and graded to separate it into different mesh sizes for application. As a preferred embodiment, the atomized powder is divided into three grades: -800 mesh, -500 mesh, and -325 mesh; the preferred powder ratio is -800:-500:-325 = 1:3:6; the preferred powder mixing method is ultrasonic dispersion; and the bulk density range is 3.2–4.5 g / cm³.

[0111] Appendix 13 below lists the performance differences with different powder ratios, based on the evaluation method for integrally molded inductors.

[0112] Appendix Table 13 (Comparison of Ring Compression Test Performance with Different Powder Ratios)

[0113]

[0114]

[0115] However, in the application of the atomized powder preparation method in this invention, since the atomized powder is spherical in shape, there may be a lot of gaps between the powder particles; therefore, if inductor products are directly produced using this method, the product performance will still be limited.

[0116] In this embodiment, in step S3, before the amorphous nanocrystalline powder is subjected to insulating coating treatment, a filler powder is added to fully mix it. The filler powder is selected as iron-silicon-chromium and / or carbonyl iron powder, which fills the gaps between the amorphous nanocrystalline powders to form an amorphous nanocrystalline mixed powder, thereby effectively increasing the bonding strength between the powder particles and effectively improving the density of the subsequent product, thus improving the product performance.

[0117] In the application of amorphous nanocrystalline mixed powder, the particle size range of the atomizing powder used will be -325 to +500 mesh, while the particle size range of the filler powder will be -600 to 800 mesh. The addition ratio of the filler powder to the overall amorphous nanocrystalline mixed powder is 2 to 15%.

[0118] The results of the ring compression test will be listed in Appendix 14 and Appendix 15 below, showing the results of the test under different ratios of amorphous nanocrystalline powder with iron-silicon-chromium powder, carbonyl iron powder, etc.

[0119] Appendix Table 14 (Comparison of the performance of amorphous nanocrystalline powder and iron-silicon-chromium powder in ring compression test)

[0120]

[0121] Appendix Table 15 (Comparison of Ring Compression Test Performance of Amorphous Nanocrystalline Powder and Carbonyl Iron Powder)

[0122]

[0123] Example 5:

[0124] Based on step S3, this invention further provides an insulating coating treatment method to meet the preparation requirements of the coating powder, the specific process steps of which are as follows:

[0125] A1. The obtained amorphous nanocrystalline powder is mixed with nitric acid solution and acetone solution. The resulting mixture is placed in a sealed container and heated in a water bath at a constant temperature and kept warm. The preferred heating temperature for the water bath is 45 degrees Celsius, and the preferred holding time is 30 minutes.

[0126] A2. The mixture in the sealed container is stirred to allow for a full reaction between the mixtures. The stirring method can be selected as using a magnetic stir bar to fully stir the mixture in the sealed container or using ultrasound to output to the inside of the sealed container to ultrasonically disperse and mix the mixture. Based on the application of nitric acid solution as a passivating agent, a uniform oxide film will be generated on the surface of the amorphous nanocrystalline powder, forming a coated powder.

[0127] A3. After the reaction is complete, open the sealed container to allow the acetone inside to evaporate; then remove the coated powder.

[0128] In a preferred embodiment, based on the mass of the amorphous nanocrystalline powder, the nitric acid solution accounts for 1.2–2.4 wt% of the mass of the amorphous nanocrystalline powder, and the nitric acid solution can be selected as 68% concentrated nitric acid; the acetone solution accounts for 30–40 wt% of the mass of the amorphous nanocrystalline powder. No corresponding nitric acid reaction waste liquid is generated in this process, and no environmental pollution is caused.

[0129] In the above process, the binder material used is a mixture of silicone resin, epoxy resin, and curing agent, with a mass ratio of silicone resin: epoxy resin: curing agent = 14.5:3:1. This binder material accounts for 1.0-5 wt% of the amorphous nanocrystalline powder.

[0130] In the above process, the lubricant used is zinc stearate.

[0131] In the above process, the pressing pressure is controlled at 500-800 MPa.

[0132] Example 6:

[0133] After obtaining the coated powder, the present invention will apply a pre-annealing treatment to effectively promote the insulating coating effect of the powder, effectively remove the stress generated in the powder preparation process and insulating stirring process, and volatilize harmful substances introduced in the insulating coating process.

[0134] The resulting coated powder is then subjected to a pre-annealing treatment, with the annealing temperature range being Tx-100 to Tx+80 degrees Celsius, where Tx is the crystallization temperature of the amorphous nanocrystals.

[0135] For nanocrystalline powders, the formation of ultracrystals can be achieved, thus realizing crystallization. The selected pre-annealing temperature is 420-570℃, and the annealing time is 30-80min.

[0136] As shown in Tables 16 to 18, based on the application of the corresponding alloy composition, the performance evaluation results of the coated powders prepared by different compositions after pre-annealing at different temperatures will have the following performance characteristics.

[0137] Note: The loss test conditions for the sample were 100kHz and 100mT, and the test results are in kW / m3.

[0138] Appendix Table 16 (Comparison of ring pressing test performance of powders with different compositions at different pre-annealing temperatures)

[0139]

[0140] Appendix Table 17 (Comparison of ring pressing test performance of powders with different compositions at different pre-annealing temperatures)

[0141]

[0142] Appendix Table 18 (Comparison of ring pressing test performance of powders with different compositions at different pre-annealing temperatures)

[0143]

[0144]

[0145] The pre-annealed coated powder will undergo further molding to obtain the finished insulating powder. Specifically, in its secondary coating process, the binder used is epoxy resin, silicone resin, inorganic silicone, etc., and the diluent can be acetone, ethanol, purified water, etc. The proportion of binder is 0.5-5.0%, and the proportion of diluent is 0.5-10%, preferably 1.2-3.0% and 3-10%. The uniform mixing process can be carried out at room temperature or under heating conditions, with the heating temperature preferably 50-120℃.

[0146] The lubricant can be selected from paraffin wax, zinc stearate, magnesium stearate, etc., with an addition ratio of 0.2% to 1.5%. After mixing evenly, the insulating powder is obtained.

[0147] Example 7:

[0148] In the application of step S5, in order to simplify the pressing and molding process of the inductor, the present invention has made improvements to the pressing and molding process for the integrally molded inductor structure.

[0149] Specifically, the obtained amorphous nanocrystalline insulating powder is heated and further stirred to ensure that the amorphous nanocrystalline insulating powder is heated evenly; the amorphous nanocrystalline insulating powder is heated to 100-250 degrees Celsius and then kept warm for later use.

[0150] Once the corresponding molding cavity is prepared, a pre-fabricated coil is designed for the inductor. This pre-fabricated coil is placed into the molding cavity, and heated amorphous or nanocrystalline insulating powder is filled in. The inductor is then pressed and molded using conventional cold pressing equipment to obtain a monolithic inductor blank. During this pressing process, the pressure range is 400–800 MPa.

[0151] Appendix 19 below shows the performance differences of amorphous and nanocrystalline insulating powders under different heating temperatures when cold-pressed using cold pressing equipment.

[0152] Appendix Table 19 (Comparison of performance of different powders in temperature ring pressing test)

[0153]

[0154]

[0155] Then, the obtained integral inductor blank is baked at a temperature range of 150 to 220 degrees Celsius for 1 to 2.5 hours; then, depending on the design requirements of the specific product, the lead portion of the inductor is bent to obtain the inductor.

[0156] Furthermore, in order to improve the magnetic permeability of the product and reduce coil deformation, a step-by-step molding and assembly method can be adopted to manufacture the inductor.

[0157] For example, for an inductor product using a combination of T-shaped and U-shaped pre-formed magnets, corresponding T-shaped and U-shaped molding cavities can be provided according to the structural characteristics. Heated amorphous or nanocrystalline insulating powder is then filled into the corresponding molding cavities to first produce the T-shaped and U-shaped pre-formed magnets. Then, a coil is placed between the T-shaped and U-shaped pre-formed magnets, and further pressing is performed by filling with powder to obtain the corresponding inductor product.

[0158] On the other hand, after the coil is placed in the gap between the T-shaped pre-made magnet and the U-shaped pre-made magnet, magnetic glue can be used to bond the contact boundary between the two and fill the gap inside the product to obtain the desired inductor product.

[0159] Based on the definition of "amorphous nanocrystals", the aforementioned amorphous nanocrystal alloy products can be considered as applications of selected amorphous alloy products, amorphous and nanocrystal alloy products, or nanocrystal alloy products.

[0160] The above description is only a preferred embodiment of the present invention. For those skilled in the art, modifications can still be made to the embodiments without departing from the implementation principle of the present invention, and the corresponding modifications should also be considered within the protection scope of the present invention.

Claims

1. An inductor comprising an alloy magnet and a coil, characterized in that, The alloy magnet has an alloy composition including Fe. 75 Si 11 B9C 2.5 Cr 2.3 Mn 0.2 or Fe 74.8 Si 11 B9C 1.5 Cr 2.5 Mn 0.2 P1 or Fe 74.8 Si 11 B9C 0.5 Cr 1.5 Mn 0.2 P2 or Fe 73.8 Si 11 B9C 1.5 Cr 1.5 Mn 0.2 P2 or Fe 79 Si 11 B7C 0.5 Cr 0.3 Mn 0.2 P2 or Fe 79 Si9B 6.2 C 0.5 Cr 0.3 Mn1P4 or Fe 74.8 Si 11 B9C 1.5 Cr 2.5 Mn 0.2 Mo1 or Fe 76.8 Si 11 B9C 0.5 Cr 1.5 Mn 0.2 Mo1 or Fe 73.8 Si 11 B9C 1.5 Cr 1.5 Mn 1.2 Mo1 or Fe 78 Si 11 B7C 0.5 Cr 0.5 Mn1Mo2 or Fe 74.8 Si 11 B9C 1.5 Cr 2.5 Mn 0.2 Ni1 or Fe 74.8 Si 11 B9C 0.5 Cr 1.5 Mn 0.2 Ni2 or Fe 74.8 Si 11 B7C 1.5 Cr 1.5 Mn 0.2 Ni3 or Fe 76.8 Si 11 B7C 0.5 Cr 0.5 Mn 0.2 Ni4.

2. The method for preparing the inductor as described in claim 1, characterized in that, Includes the following steps: S1. The raw materials are blended and smelted according to the above-mentioned molecular formula to prepare a master alloy; S2. The obtained master alloy is prepared into powder by means of belt crushing and powder preparation or atomization powder preparation to obtain amorphous nanocrystalline powder. S3. The obtained amorphous nanocrystalline powder is subjected to insulating coating treatment to obtain coated powder; S4. The obtained coated powder is subjected to molding treatment to obtain amorphous nanocrystalline insulating finished powder. S5. The obtained amorphous nanocrystalline insulating powder is pressed into shape and baked to cure, so as to obtain an inductor.

3. The preparation method according to claim 2, characterized in that, In step S3, the insulation coating process includes the following steps: S3-1. Mix the obtained amorphous nanocrystalline powder with nitric acid solution and acetone solution. Place the mixture in a sealed container and heat it in a water bath at a constant temperature and keep it warm. S3-2. After the mixture has reacted fully, open the sealed container to allow the acetone to evaporate and obtain the coated powder.

4. The preparation method according to claim 2, characterized in that, In step S3, before the obtained amorphous nanocrystalline powder is subjected to insulating coating treatment, iron-silicon-chromium and / or carbonyl iron powder is added and thoroughly stirred and mixed to fill the gaps between the amorphous nanocrystalline powder.

5. The preparation method according to claim 2, characterized in that, Between steps S3 and S4, the following steps are also included: S3-1. The obtained coated powder is subjected to pre-annealing treatment to promote its insulation passivation reaction; the annealing temperature range of the pre-annealing treatment is Tx-100 to Tx+80 degrees Celsius, where Tx is the crystallization temperature of amorphous nanocrystals.

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