阅读说明：本技术 一种耐高温浸锡的高性能镍锌软磁铁氧体材料及制备方法 (High-temperature-resistant tin-immersion high-performance nickel-zinc soft magnetic ferrite material and preparation method thereof ) 是由 蒋玉梅 郑国友 于 2021-09-30 设计创作，主要内容包括：本发明属于软磁铁氧体技术领域,公开了一种耐高温浸锡的高性能镍锌软磁铁氧体材料及其制备方法。本发明耐高温浸锡的高性能镍锌软磁铁氧体材料由主成份和添加剂组成,其中,所述主成分由Fe-(2)O-(3)：47～52.5mol％,NiO：16.2～24.06mol％,ZnO：19.3～27.44mol％,以及CuO：4.05～8.12mol％组成；所述添加剂由Al-(2)O-(3)：0.01～0.5wt％,ZrO：0.01～0.5wt％,V-(2)O-(5)：0.05～0.8wt％,Bi-(2)O-(3)：0.05～0.6wt％,以及CaCO-(3)：0.05～0.5wt％组成。该高性能镍锌软磁铁氧体材料主要针对现有技术NiZn软磁铁氧体材料在客户端使用存在严重的浸锡开裂不良、直流叠加不良、强度低等问题,通过改良主成分和添加剂及制作工艺,可批量生产获得高磁导率高Bs高强度且满足耐高温浸锡工艺的镍锌铁氧体材料。(The invention belongs to the technical field of soft magnetic ferrite, and discloses a high-temperature-resistant tin-immersion high-performance nickel-zinc soft magnetic ferrite material and a preparation method thereof. The high-performance nickel-zinc soft magnetic ferrite material resistant to high-temperature tin immersion comprises a main component and an additive, wherein the main component is Fe 2 O 3 : 47-52.5 mol%, NiO: 16.2-24.06 mol%, ZnO: 19.3 to 27.44 mol%, and CuO: 4.05-8.12 mol%; the additive is made of Al 2 O 3 ：0.01～0.5wt％，ZrO：0.01～0.5wt％，V 2 O 5 ：0.05～0.8wt％，Bi 2 O 3 : 0.05 to 0.6 wt%, and CaCO 3 : 0.05 to 0.5 wt%. The high-performance nickel-zinc soft magnetic ferrite material mainly aims at the problems of serious poor tin immersion cracking, poor direct current superposition, low strength and the like existing in the use of the NiZn soft magnetic ferrite material at a client in the prior art, and improves the main componentsAnd an additive and a manufacturing process, and the nickel-zinc ferrite material which has high magnetic permeability, high Bs and high strength and meets the high-temperature-resistant tin immersion process can be produced in batches.)

1. The high-temperature-immersion-resistant high-performance nickel-zinc soft magnetic ferrite material is characterized by comprising a main component and an additive, wherein the main component is Fe₂O₃: 47-52.5 mol%, NiO: 16.2-24.06 mol%, ZnO: 19.3 to 27.44 mol%, and CuO: 4.05-8.12 mol%; the additive is made of Al₂O₃：0.01～0.5wt％，ZrO：0.01～0.5wt％，V₂O₅：0.05～0.8wt％，Bi₂O₃: 0.05 to 0.6 wt%, and CaCO₃: 0.05 to 0.5 wt%.

2. The high-temperature-immersion-tin-resistant high-performance nickel-zinc soft magnetic ferrite material as claimed in claim 1, wherein the main component is made of Fe₂O₃: 48-51.5 mol%, NiO: 17.25-21.02 mol%, ZnO: 19.3 to 26.64 mol%, and CuO: 5.05 to 8.02 mol%.

3. The high-temperature-immersion-tin-resistant high-performance nickel-zinc soft magnetic ferrite material as claimed in claim 1, wherein the additive is Al₂O₃：0.05～0.3wt％，ZrO：0.01～0.2wt％，V₂O₅：0.1～0.5wt％，Bi₂O₃0.05 to 0.3 wt%, and CaCO₃0.1 to 0.3 wt%.

4. A method for preparing a high-temperature-immersion-tin-resistant high-performance nickel-zinc soft magnetic ferrite material according to any one of claims 1 to 3, which comprises the following steps:

(1) material mixing and ball milling: weighing Fe according to the proportion of the required main components₂O₃Adding deionized water into a sand mill for mixing and crushing, and performing ball milling for 0.5-2 h to obtain primary ball-milled powder;

(2) pre-burning: ventilating and drying the primary ball-milling powder, putting the powder in a box type pre-sintering furnace for pre-sintering, controlling the pre-sintering temperature to be 930 +/-10 ℃, sintering for 1-3 h, and cooling to obtain a primary pre-sintering material;

(3) secondary sanding: adding Al into the pre-sintering material according to the amount of the required additive₂O₃、ZrO、V₂O₅、Bi₂O₃、CaCO₃Then, putting the powder into a sand mill, adding deionized water into the sand mill, performing secondary sand milling for 1-3 h, controlling the particle size to be 0.6-1.3 mu m, forming normal distribution, drying, grinding and dispersing to obtain secondary sand milling powder;

(4) spray granulation: adding PVA with the mass concentration of 8-12% and a defoaming agent with the weight of 0.01-0.1 wt% of dry powder into the secondary sand grinding material, and then carrying out centrifugal spray granulation to obtain particles with the particle size of 50-250 microns;

(5) molding: PVA with the mass concentration of 2-8% is added into the granular material, the mixture is uniformly stirred and pressed by a powder forming machine to form the granular material with the density of 3.05-3.25 g/cm³And (5) blank.

(6) And (3) sintering: and (3) sintering the blank in a roller kiln in an air atmosphere, controlling the sintering temperature to be 1050-1200 ℃, heating at 2-3 ℃/min, heating to a high-temperature area, preserving the heat for 3-5 h, cooling at 3-5 ℃/min, and cooling to obtain the NiZn ferrite magnetic core.

5. The method for preparing the high-temperature-immersion-tin-resistant high-performance nickel-zinc soft magnetic ferrite material according to claim 4, wherein the defoaming agent is n-octanol.

Technical Field

The invention relates to the technical field of soft magnetic ferrite, in particular to a high-performance nickel-zinc soft magnetic ferrite material resistant to high-temperature tin immersion and a preparation method thereof.

Background

The nickel-zinc ferrite has the characteristics of high magnetic permeability, high resistivity and high use frequency, is suitable for various surface-mounted elements, and is widely applied to various intelligent wearing, 5G communication, electric vehicles, consumer electronics and the like. Along with the increasing automation degree, the requirements of the automation process of an inductance device manufacturer on the physical properties of the ferrite are also increasing, and the physical properties are required to be improved on the premise of keeping the original electrical properties; in particular to a magnetic CORE similar to DR + RI matched or a flat DR CORE directly plated on the surface of the magnetic CORE. The current domestic NiZn series ferrite material has the main problems that the inductance meets the requirement and the direct current superposition cannot be achieved; even if the inductance and the direct current superposition meet the requirements, the strength can not meet the requirements; most importantly, the high-temperature tin immersion requirement cannot be met. The prior NiZn series material in China can only meet the tin immersion requirement of a common process, namely the tin immersion temperature of about 380 ℃, but can not meet the tin immersion process requirement of high temperature of 430 ℃. Companies such as Coilcraft, hamarta, and sunrise have hard requirements for mechanical strength and resistance to high temperature wicking conditions. Nowadays, electronic products are developed towards flat, thin and surface mounting, and the size of soft magnetic elements is smaller and smaller, so that the inductor material is required to have higher saturation magnetic induction Bs and higher mechanical strength, and can meet the requirements of high-temperature-resistant tin immersion process.

Disclosure of Invention

The invention aims to overcome the defects of the background technology and provide a high-performance nickel-zinc soft magnetic ferrite material with high temperature resistance and tin immersion resistance. The high-performance nickel-zinc soft magnetic ferrite material mainly aims at the problems of serious poor tin immersion cracking, poor direct current superposition, low strength and the like existing in the NiZn soft magnetic ferrite material used at a client in the prior art, and can be produced in batches by improving the main components, the additives and the manufacturing process to obtain the nickel-zinc ferrite material which has high magnetic conductivity, high Bs (saturation magnetic flux) and high strength and meets the high-temperature resistant tin immersion process.

In order to achieve the aim of the invention, the high-performance nickel-zinc soft magnetic ferrite material resisting high-temperature tin immersion consists of a main component and an additive, wherein the main component is Fe₂O₃: 47-52.5 mol%, NiO: 16.2-24.06 mol%, ZnO: 19.3 to 27.44 mol%, and CuO: 4.05-8.12 mol%; the additive is made of Al₂O₃：0.01～0.5wt％，ZrO：0.01～0.5wt％，V₂O₅：0.05～0.8wt％，Bi₂O₃: 0.05 to 0.6 wt%, andCaCO₃: 0.05-0.5 wt% (wt% is the weight percentage of the additive in the total feeding amount).

Preferably, in some embodiments of the invention, the main component consists of Fe₂O₃: 48-51.5 mol%, NiO: 17.25-21.02 mol%, ZnO: 19.3 to 26.64 mol%, and CuO: 5.05 to 8.02 mol%.

Preferably, in some embodiments of the invention, the additive consists of Al₂O₃：0.05～0.3wt％，ZrO：0.01～0.2wt％，V₂O₅：0.1～0.5wt％，Bi₂O₃0.05 to 0.3 wt%, and CaCO₃0.1 to 0.3 wt%.

On the other hand, the invention also provides a preparation method of the high-temperature-resistant tin-immersion-resistant high-performance nickel-zinc soft magnetic ferrite material, which comprises the following steps:

(1) material mixing and ball milling: weighing Fe according to the proportion of the required main components₂O₃Adding deionized water into a sand mill for mixing and crushing, and performing ball milling for 0.5-2 h to obtain primary ball-milled powder;

(2) pre-burning: ventilating and drying the primary ball-milling powder, putting the powder in a box type pre-sintering furnace for pre-sintering, controlling the pre-sintering temperature to be 930 +/-10 ℃, sintering for 1-3 h, and cooling to obtain a primary pre-sintering material;

(3) secondary sanding: adding Al into the pre-sintering material according to the amount of the required additive₂O₃、ZrO、V₂O₅、Bi₂O₃、CaCO₃Then, putting the powder into a sand mill, adding deionized water into the sand mill, performing secondary sand milling for 1-3 h, controlling the particle size to be 0.6-1.3 mu m, forming normal distribution, drying, grinding and dispersing to obtain secondary sand milling powder;

(4) spray granulation: adding PVA with the mass concentration of 8-12% and a defoaming agent with the weight of 0.01-0.1 wt% of dry powder into the secondary sand grinding material, and then carrying out centrifugal spray granulation to obtain particles with the particle size of 50-250 microns;

(5) molding: adding PVA with the mass concentration of 2-8% into the granules, uniformly stirring, and performing powder moldingThe density of the product is 3.05-3.25 g/cm³And (5) blank.

(6) And (3) sintering: and (3) sintering the blank in a roller kiln in an air atmosphere, controlling the sintering temperature to be 1050-1200 ℃, heating at 2-3 ℃/min, heating to a high-temperature area, preserving the heat for 3-5 h, cooling at 3-5 ℃/min, and cooling to obtain the NiZn ferrite magnetic core.

Further, in some embodiments of the invention, the antifoaming agent is n-octanol.

Compared with the prior art, the invention has the following advantages:

(1) according to the invention, through formula development and trace element modification, the problems of low magnetic conductivity, low Bs, low strength, poor heat resistance and the like are overcome, and the high-performance NiZn soft magnetic ferrite material which has high magnetic conductivity, high Bs and high strength and can meet the high-temperature-resistant tin immersion process is developed.

(2) The NiZn ferrite material prepared by the invention has the characteristics of high magnetic conductivity, high Bs, high strength, high temperature immersion resistance and the like, wherein:

initial permeability μ i [25 ℃ ], ± 450 ± 25% (@1KHz, 0.25V);

saturation magnetic induction intensity Bs [25 ℃ C ] is more than or equal to 440mT (@50Hz, 4000A/m);

curie temperature Tc [ ° C ] is not less than 230;

resistivity rho (omega. m) is more than or equal to 10⁶；

Sintered density d (g/cm)³)：5.1。

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail with reference to the following embodiments. Additional aspects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention. It is to be understood that the following description is only illustrative of the present invention and is not to be construed as limiting the present invention.

The terms "comprises," "comprising," "includes," "including," "has," "having," "contains," "containing," or any other variation thereof, as used herein, are intended to cover a non-exclusive inclusion. For example, a composition, process, method, article, or apparatus that comprises a list of elements is not necessarily limited to only those elements but may include other elements not expressly listed or inherent to such composition, process, method, article, or apparatus.

When an amount, concentration, or other value or parameter is expressed as a range, preferred range, or as a range of upper preferable values and lower preferable values, this is to be understood as specifically disclosing all ranges formed from any pair of any upper range limit or preferred value and any lower range limit or preferred value, regardless of whether ranges are separately disclosed. For example, when a range of "1 to 5" is disclosed, the described range should be interpreted to include the ranges "1 to 4", "1 to 3", "1 to 2 and 4 to 5", "1 to 3 and 5", and the like. When a range of values is described herein, unless otherwise stated, the range is intended to include the endpoints thereof and all integers and fractions within the range.

Furthermore, the description below of the terms "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above are not necessarily for the same embodiment or example. Further, the technical features of the embodiments of the present invention may be combined with each other as long as they do not conflict with each other.

Example 1

The high-performance nickel-zinc soft magnetic ferrite material capable of resisting high-temperature tin immersion is characterized in that the proportion of main components and additives in the material is shown in Table 1, and the preparation method comprises the following steps:

1. batching ball mill

According to the proportion of each main component in the table 1, Fe is used respectively₂O₃Calculating the proportion of ZnO, NiO and CuO, and weighing Fe₂O₃NiO, ZnO and CuO, then adding deionized water into a sand mill for mixing and crushing, and performing ball milling for 1.5h to obtain primary ball-milled powder.

2. Pre-firing

And (3) ventilating and drying the primary ball-milling powder, putting the powder in a box type pre-sintering furnace for pre-sintering, controlling the pre-sintering temperature to be 930 +/-10 ℃, sintering for 2 hours, and cooling to obtain the primary pre-sintering material.

3. Secondary sand milling

Adding additives into the pre-sintering material according to the component ratio in the table 1: al (Al)₂O₃、ZrO、V₂O₅、Bi₂O₃、CaCO₃And then putting the powder into a sand mill, adding deionized water into the sand mill, performing secondary sand milling for 2 hours, controlling the particle size to be 0.6-1.3 mu m (the particle size of powder particles is normally distributed), drying, grinding and dispersing to obtain secondary sand milling powder.

4. Spray granulation

Adding PVA with the mass concentration of 10% and defoaming agent n-octanol with the weight of 0.05 wt% of dry powder into the secondary sand grinding material, and then carrying out centrifugal spray granulation in a spray tower to obtain particles with the particle size of 50-250 microns.

5. Shaping of

PVA with the mass concentration of 5 percent is added into the granular material, the mixture is evenly stirred and pressed into granules with the density of 3.15g/cm by a powder forming machine³And (5) blank.

6. Sintering

And (3) sintering the blank in a roller kiln in an air atmosphere, controlling the sintering temperature to be 1050-1200 ℃, heating at 2.5 ℃/min, heating to a high-temperature area, preserving the heat for 4h, cooling at 4 ℃/min, and cooling to obtain the NiZn ferrite magnetic core.

Examples 2 to 4 and comparative examples 1 to 4

The preparation method is substantially the same as example 1 except that the compounding ratio of each main component and additive in the material is shown in table 1.

TABLE 1 examples 1-4 and comparative examples 1-4 main ingredient formulations and additive ratios

The sintered cores of the examples and comparative examples were tested and evaluated: testing the initial permeability mu i of the magnetic ring sample by using an LCR tester E4980A under the condition that the number of turns N is 20Ts by using a standard ring; the saturated magnetic induction intensity Bs (50Hz/4000A/m) of the sample is tested by a SY-8258 type B-H analyzer, and the Curie temperature Tc of the sample is tested by an LCR-4225 type inductance analyzer and a special oven; adopting an Agilent4339B high-resistance meter to test insulation resistance values R at two ends of phi 10 x 2mm, and calculating the resistivity rho; the mechanical strength was measured by a DPX-20TR Strength tester, and the core was immersed for 2 times in a tin furnace at T ═ 435. + -. 10 ℃ for 3 seconds, under a 20-fold magnification to see whether the core cracked.

Specific performance test results are shown in table 2.

TABLE 2 Performance test tables for examples 1 to 4 and comparative examples 1 to 4

In order to realize low-temperature sintering and obtain excellent electromagnetic performance, the NiCuZn ferrite material provided by the invention is added with different additive proportions on the basis of main components, and has a key improvement effect on the influence of high-temperature-resistant tin immersion and mechanical strength; addition of Bi₂O₃To facilitate low temperature sintering of the material; addition of V₂O₅ZrO and AL₂O₃Improve the strength characteristic and high-temperature-resistant tin immersion characteristic of the material and inhibit Fe²⁺Also plays a role in adding CaCO₃And AL₂O₃The method is beneficial to increasing the thickness of the crystal boundary, inhibiting the growth of crystal grains and improving the Q value of the material; comparative example 1 is AL as₂O₃、V₂O₅When ZrO is not added, the high-temperature-resistant tin immersion cannot meet the tin immersion process requirement at the high temperature of 430 ℃, the mechanical strength is poorer than that of the embodiment, and the effect cannot be achieved; comparative example 2 when AL₂O₃When ZrO is not added, but V is added₂O₅The mechanical strength was improved, and the strength was inferior to that of the examples and the resistance was highThe warm immersion tin can not meet the requirements of the immersion tin process at the high temperature of 430 ℃; mechanical strength was also inferior to the examples; comparative example 3 when V₂O₅When the ZrO is not added and the adding proportion of ZrO is at the lowest limit, the high-temperature resistant tin immersion can not meet the tin immersion process requirement at the high temperature of 430 ℃, the mechanical strength is poorer than that of the embodiment, and the effect can not be achieved; comparative example 4 when V₂O₅Not added and Al₂O₃When the ZrO adding proportion is at the lowest limit, the high-temperature resistant tin immersion can not meet the tin immersion process requirement at the high temperature of 430 ℃, the mechanical strength is poorer than that of the proportion 3, and the effect can not be achieved; al is added in the total amount₂O₃ 0.05～0.3wt％，ZrO 0.01～0.2wt％，V₂O₅ 0.1～0.5wt％，Bi₂O₃ 0.05～0.3wt％，CaCO₃When the content is 0.1-0.3 wt%, the material can obtain higher magnetic conductivity, high Bs, high strength and high-temperature-resistant tin immersion property. Through the mutual cooperation of the components, the NiCuZn ferrite material provided by the invention can be sintered at the temperature of below 1140 ℃, and the obtained material resistivity is 10⁹The thickness is more than omega cm, and the insulating effect can be achieved; the obtained material has the initial magnetic permeability of 450, Bs is more than 440mT, the local temperature is more than 240 ℃, and the material has good mechanical strength and the characteristic of no cracking of 430 ℃ tin immersion, and is particularly suitable for products of miniaturized surface-mounted inductance devices.

It will be understood by those skilled in the art that the foregoing is only exemplary of the present invention, and is not intended to limit the invention, which is intended to cover any variations, equivalents, or improvements therein, which fall within the spirit and scope of the invention.