Nickel-zinc copper ferrite material, and preparation method and application thereof

Abstract

The application relates to a nickel-zinc-copper ferrite material and a preparation method and application thereof, and the nickel-zinc-copper ferrite material comprises main components and auxiliary components; the main components comprise the following components in a total mass percentage of 100wt%: Fe2O3 64.5-66.5wt%, NiO 9-12wt%, ZnO 13.5-18.5wt%, CuO 3-10wt%; the auxiliary components comprise the following components in the total mass percentage of the main components: Bi2O3 0.3-1.5wt%, Co2O3 0.1-0.6wt%, CaCO3 0.03-0.08wt%, ZrO2 0.01-0.1wt%. The nickel-zinc-copper ferrite material prepared by the application has high saturation magnetic induction intensity, high magnetic permeability, high Curie temperature, low residual magnetic induction intensity and low specific temperature coefficient, and can be better applied to power inductance or common mode inductance.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of ferrite, in particular to a nickel-zinc-copper ferrite material and a preparation method and application thereof. BACKGROUND

[0002] Ferrite material has been widely used in biomedical, electromagnetic devices, LED lighting, high-performance computers and other fields due to its high magnetic induction strength, high coercivity and high magnetic permeability. With the development trend of miniaturization and lightness of components, higher requirements are put forward for the magnetic properties of the mainstream nickel-zinc material in ferrite material.

[0003] The nickel-zinc ferrite material in the current research has high magnetic permeability, but low Curie temperature and saturation magnetic induction strength, which leads to low inductance after superimposed current, low energy conversion efficiency and high loss of products made of nickel-zinc material during use.

[0004] CN104402428A discloses a nickel-zinc ferrite material with high frequency, high magnetic permeability and high Q value and a preparation method thereof. The ferrite material comprises main components and doping components, and the main components and the doping components are calculated according to oxide raw materials. The main components comprise NiO 17-19mol%, ZnO 31-33mol% and the rest is Fe2O3 according to the mole percentage. The doping components comprise SnO2 0.2-0.4wt% and Dy2O3 0.002-0.004wt% according to the weight percentage of the total weight of the material. The ferrite material is prepared by the following method: weighing raw materials → first pre-burning → second pre-burning → granulating and forming → sintering. The nickel-zinc ferrite material provided by the application has high frequency and high magnetic permeability, but does not have high Bs value.

[0005] CN101169996A discloses a Mn-Zn ferrite magnetic material and a preparation method thereof. The main components and contents of the Mn-Zn ferrite magnetic material are calculated as oxides: Fe2O3 is 52-56mol%; ZnO is 2-10mol%; MnO is 38-42mol%; and the auxiliary components are one or a combination of CaO: 400-800ppm, Nb2O5: 100-400ppm, ZrO2: 100-800ppm and Co2O3: 1000-5000ppm. It is a Mn-Zn ferrite magnetic material with high saturation magnetic induction strength, low power consumption under super-high temperature conditions and excellent electromagnetic properties. The patent simultaneously adds many impurities in the main components Fe2O3, NiO, ZnO and CuO of the ferrite to achieve high saturation magnetic induction strength and high Curie temperature, but the magnetic permeability after sintering is low, and the temperature stability needs to be studied.

[0006] CN109279886A discloses a nickel-zinc-copper soft ferrite material, which is composed of the following components by mass: 40-60 parts of iron oxide powder, 10-20 parts of nickelous oxide, 5-10 parts of zinc sulfate, 5-10 parts of antimony trioxide, 3-6 parts of sodium dodecylbenzenesulfonate, 2-5 parts of sodium hypophosphite, 2-5 parts of expanded perlite powder, 2-5 parts of methyl methacrylate, 1-3 parts of sodium benzoylsulfonimide, 1-3 parts of tungsten trioxide, and the balance of deionized water. The nickel-zinc-copper soft ferrite material provided by this invention can meet the requirements of low loss under high-frequency use, but its other magnetic properties need to be improved.

[0007] Therefore, in view of the shortcomings of the existing technology, there is an urgent need to provide a nickel-zinc-copper ferrite material with high magnetic permeability, high Curie temperature, high saturation magnetic induction intensity and low specific temperature coefficient. Summary of the Invention

[0008] The purpose of the present invention is to provide a nickel-zinc-copper ferrite material and its preparation method and application. By limiting the reasonable ratio of raw materials, the prepared nickel-zinc-copper ferrite material has the characteristics of high magnetic permeability, high Curie temperature, high saturation magnetic induction intensity, low residual magnetic induction intensity and low specific temperature coefficient.

[0009] In order to achieve the purpose of the invention, the present invention adopts the following technical solutions:

[0010] In a first aspect, the present invention provides a nickel-zinc-copper ferrite material, which includes a main component and an auxiliary component; based on the total mass percentage of 100wt%, the main component includes: Fe2O3 64.5-66.5wt%, NiO 9-12wt%, ZnO 13.5-18.5wt%, and CuO 3-10wt%; based on the total mass percentage of the main components, the auxiliary components include: Bi2O3 0.3-1.5wt%, Co2O3 0.1-0.6wt%, CaCO3 0.03-0.08wt%, and ZrO2 0.01-0.1wt%.

[0011] The present invention can obtain nickel-zinc-copper ferrite materials with high magnetic permeability and Curie temperature by controlling the content range of the main components; in order to ensure high saturation magnetic induction intensity and low specific temperature coefficient characteristics, it is necessary to adjust the overall content of Fe2O3, ZnO, NiO and CuO; by adjusting the auxiliary component Ca 2+ and Bi 3+ The combined substitution of can improve the magnetic permeability and achieve high-frequency charging efficiency; 2+ 、Co 3+ A small amount of substitution can reduce the imaginary part of the magnetic permeability to achieve low loss characteristics; by Ca 2+ 、Co 3+and Bi 3+ or Zr 4+ The combined substitution of can regulate the saturation magnetic induction intensity to achieve the applicability of devices in extreme environments. The nickel-zinc-copper ferrite material produced by the present invention has high saturation magnetic induction intensity, high magnetic permeability, high Curie temperature, low residual magnetic induction intensity, and low specific temperature coefficient, and can be better applied to power inductors or common-mode inductors.

[0012] The mass percentage of Fe2O3 in the main component is 64.5-66.5wt%, for example, it can be 64.5wt%, 65wt%, 65.5wt%, 66wt% or 66.5wt%, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0013] The mass percentage of NiO in the main component is 9-12wt%, for example, it can be 9wt%, 9.5wt%, 10.3wt%, 11.5wt% or 12wt%, but is not limited to the listed values. Other values ​​not listed within the numerical range are also applicable.

[0014] The mass percentage of ZnO in the main component is 13.5-18.5wt%, for example, it can be 13.5wt%, 14.5wt%, 15.5wt%, 16.5wt% or 18.5wt%, but is not limited to the listed values. Other values ​​not listed within the numerical range are also applicable.

[0015] The mass percentage of CuO in the main component is 3-10wt%, for example, it can be 3wt%, 5wt%, 6wt%, 8wt% or 10wt%, but is not limited to the listed values. Other values ​​not listed within the numerical range are also applicable.

[0016] The mass percentage of Bi2O3 in the auxiliary component is 0.3-1.5wt% of the total mass percentage of the main component, for example, it can be 0.3wt%, 0.5wt%, 0.8wt%, 1.2wt% or 1.5wt%, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0017] The mass percentage of Co2O3 in the auxiliary component is 0.1-0.6wt% of the total mass percentage of the main component, for example, it can be 0.1wt%, 0.2wt%, 0.3wt%, 0.4wt% or 0.6wt%, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0018] The mass percentage of CaCO3 in the auxiliary component is 0.03-0.08wt% of the total mass percentage of the main component, for example, it can be 0.03wt%, 0.04wt%, 0.05wt%, 0.06wt% or 0.08wt%, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0019] The mass percentage of ZrO2 in the auxiliary component is 0.01-0.1wt% of the total mass percentage of the main component, for example, it can be 0.01wt%, 0.03wt%, 0.05wt%, 0.08wt% or 0.1wt%, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0020] Preferably, the total mass percentage of ZnO+CuO in the main component is 22-26wt%, for example, it can be 22wt%, 23wt%, 23.5wt%, 24wt% or 26wt%, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0021] In the present invention, the total amount of ZnO and CuO needs to be controlled within a reasonable range. If the total amount exceeds the limit, even if the content of each main component is within the required range, the magnetic permeability and saturation magnetic induction intensity Bs of the prepared nickel-zinc-copper ferrite material will be reduced.

[0022] Preferably, the total mass percentage of Bi2O3+ZrO2 in the auxiliary components is 0.35-1.55wt% of the total mass percentage of the main components, for example, it can be 0.35wt%, 0.5wt%, 0.8wt%, 1wt% or 1.55wt%, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0023] In the present invention, the total amount of Co2O3 and CaCO3 needs to be controlled within a reasonable range. If the total amount exceeds the limited range, the magnetic permeability of the prepared nickel-zinc-copper ferrite material will be reduced even if the content of each auxiliary component is within the required range.

[0024] In a second aspect, the present invention provides a method for preparing the nickel-zinc-copper ferrite material as described in the first aspect, the preparation method comprising the following steps:

[0025] (1) Weighing the main components according to the proportion, and then wet ball milling and mixing. The obtained ball milled material is subjected to a first spray granulation and then pre-calcined to obtain a pre-calcined material;

[0026] (2) weighing auxiliary components according to a ratio, and then sequentially subjecting the auxiliary components, liquid medium, additives and the pre-sintered material obtained in step (1) to a first grinding and a second grinding, and the obtained ground material is subjected to a second spray granulation and then molded and sintered to obtain the nickel-zinc-copper ferrite material.

[0027] The preparation method of the nickel-zinc-copper ferrite material provided by the present invention is beneficial to the magnetic domain refinement of the nickel-zinc-copper ferrite material obtained by subsequent sintering by selecting reasonable process parameters, thereby ensuring high saturation magnetic induction intensity, high magnetic permeability, high Curie temperature, low residual magnetic induction intensity and low specific temperature coefficient of the nickel-zinc-copper ferrite material, thereby meeting the high performance requirements as a soft magnetic ferrite material.

[0028] Preferably, the mass ratio of the main component, the ball milling medium and the liquid medium in the wet ball milling mixing in step (1) is 1:(4-8):(0.5-1.2), for example, it can be 1:4:0.5, 1:5:0.6, 1:6:0.8, 1:7:1 or 1:8:1.2, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0029] Preferably, the ball milling media comprises zirconium balls.

[0030] Preferably, the liquid medium comprises deionized water.

[0031] Preferably, the wet ball milling mixing time in step (1) is 20-60 min, for example, 20 min, 30 min, 40 min, 50 min or 60 min, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0032] Preferably, the pre-calcination temperature in step (1) is 780-950°C, for example, it can be 780°C, 800°C, 820°C, 850°C, 880°C, 900°C or 950°C, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0033] Preferably, the pre-burning time in step (1) is 2-4 hours, for example, 2 hours, 2.5 hours, 3 hours, 3.5 hours or 4 hours, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0034] Preferably, the additives in step (2) include a binder, a dispersant and a defoaming agent.

[0035] Preferably, the mass ratio between the pre-burnt material, the liquid medium, the binder, the dispersant, and the defoaming agent in step (2) is 100:(40-150):(4-20):(0.1-2):(0.001-0.0025), for example, it can be 100:40:4:0.1:0.001, 100:70:7:0.5:0.0012, 100:100:10:1:0.0015, 100:120:15:1.5:0.002, or 100:150:20:2:0.0025, but is not limited to the listed values, other values not listed within the value range are also applicable.

[0036] Preferably, the liquid medium in step (2) comprises deionized water.

[0037] Preferably, the binder comprises any one or a combination of at least two of polyvinyl alcohol, polyvinyl butyral, hydroxyl cellulose, or polyacrylate, typically but not limitedly, the combination comprises polyvinyl alcohol and polyvinyl butyral, polyvinyl butyral, hydroxyl cellulose and polyacrylate, or polyvinyl alcohol, polyvinyl butyral, hydroxyl cellulose and polyacrylate.

[0038] Preferably, the dispersant comprises any one or a combination of at least two of citric acid amine, sodium stearate, polyacrylic acid, or triethanolamine, typically but not limitedly, the combination comprises citric acid amine and sodium stearate, sodium stearate and polyacrylic acid, or citric acid amine, sodium stearate, polyacrylic acid and triethanolamine.

[0039] Preferably, the defoaming agent comprises any one or a combination of at least two of n-octanol, tributyl phosphate, stearic acid, or polyethylene glycol, typically but not limitedly, the combination comprises n-octanol and tributyl phosphate, stearic acid and polyethylene glycol, or n-octanol, tributyl phosphate, stearic acid and polyethylene glycol.

[0040] Preferably, the rotation speed of the first grinding in step (2) is 145-265 rpm, for example, it can be 145 rpm, 180 rpm, 200 rpm, 220 rpm, or 265 rpm, but is not limited to the listed values, other values not listed within the value range are also applicable.

[0041] Preferably, the time of the first grinding in step (2) is 5-10 min, for example, it can be 5 min, 6 min, 8 min, 9 min, or 10 min, but is not limited to the listed values, other values not listed within the value range are also applicable.

[0042] Preferably, the rotation speed of the second grinding in step (2) is 270-320 rpm, for example, it can be 270 rpm, 290 rpm, 300 rpm, 310 rpm or 320 rpm, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0043] Preferably, the second grinding time in step (2) is 0.5-2h, for example, 0.5h, 0.8h, 1h, 1.5h or 2h, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0044] Preferably, the median particle size X50 of the grinding material in step (2) is 0.5-0.8 μm, and the particle size X90 with a cumulative percentage of 90% is 1.25-1.8 μm.

[0045] The median particle size X50 of the grinding material is 0.5-0.8 μm, for example, 0.5 μm, 0.6 μm, 0.7 μm or 0.8 μm, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0046] The lower median particle size X50 of the abrasive is beneficial to the magnetic domain refinement of the nickel-zinc-copper ferrite material obtained by subsequent sintering, thereby improving the magnet strength.

[0047] The particle size X90 of the abrasive at a cumulative percentage of 90% is 1.25-1.8 μm, for example, 1.25 μm, 1.5 μm, 1.6 μm, 1.7 μm or 1.8 μm, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0048] Preferably, the average particle size of the particles obtained by the second spray granulation in step (2) is 30-200 μm, for example, 30 μm, 60 μm, 100 μm, 150 μm or 200 μm, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0049] Preferably, the forming in step (2) includes forming a standard sample ring blank.

[0050] The density of the standard sample ring blank is 3.1-3.25g / cm 3 , size is H25*15*10mm.

[0051] Preferably, the sintering in step (2) is carried out in a push plate kiln.

[0052] Preferably, the sintering in step (2) includes a first heat treatment, a second heat treatment, a first cooling treatment and a second cooling treatment performed in sequence.

[0053] Preferably, the specific step of the first heat treatment comprises: heating from room temperature to 550-750℃ at a heating rate of 0.5-2℃ / min, and holding for 2-7h.

[0054] The heating rate of the first heat treatment is 0.5-2℃ / min, for example, it can be 0.5℃ / min, 0.8℃ / min, 1℃ / min, 1.5℃ / min or 2℃ / min, but is not limited to the listed values, and other values not listed in the value range are also applicable.

[0055] The room temperature refers to a temperature of 20-25℃.

[0056] The temperature end point of the first heat treatment is 550-750℃, for example, it can be 550℃, 600℃, 650℃, 700℃ or 750℃, but is not limited to the listed values, and other values not listed in the value range are also applicable.

[0057] The holding time of the first heat treatment is 2-7h, for example, it can be 2h, 3h, 5h, 6h or 7h, but is not limited to the listed values, and other values not listed in the value range are also applicable.

[0058] Preferably, the specific step of the second heat treatment comprises: continuing to heat to 950-1050℃ at a heating rate of 1-3℃ / min, and holding for 2-5h.

[0059] The heating rate of the second heat treatment is 1-3℃ / min, for example, it can be 1℃ / min, 1.5℃ / min, 2℃ / min, 2.5℃ / min or 3℃ / min, but is not limited to the listed values, and other values not listed in the value range are also applicable.

[0060] The temperature end point of the second heat treatment is 950-1050℃, for example, it can be 950℃, 980℃, 1000℃, 1020℃ or 1050℃, but is not limited to the listed values, and other values not listed in the value range are also applicable.

[0061] The holding time of the second heat treatment is 2-5h, for example, it can be 2h, 2.5h, 3h, 4h or 5h, but is not limited to the listed values, and other values not listed in the value range are also applicable.

[0062] Preferably, the specific step of the first cooling treatment comprises: cooling to 595-605℃ at a cooling rate of 2-6℃ / min in an air atmosphere.

[0063] The cooling rate of the first cooling treatment is 2-6℃ / min, for example, it can be 2℃ / min, 3℃ / min, 4℃ / min, 5℃ / min or 6℃ / min, but is not limited to the listed values, and other values not listed in the value range are also applicable.

[0064] The temperature end point of the first cooling treatment is 595-605℃, for example, it can be 595℃, 598℃, 600℃, 602℃ or 605℃, but is not limited to the listed values, and other values not listed in the value range are also applicable.

[0065] Preferably, the specific steps of the second cooling treatment include: continuing to cool to 45-55℃ at a cooling rate of 1-5℃ / min.

[0066] The cooling rate of the second cooling treatment is 1-5℃ / min, for example, it can be 1℃ / min, 2℃ / min, 3℃ / min, 4℃ / min or 5℃ / min, but is not limited to the listed values, and other values not listed in the value range are also applicable.

[0067] The temperature end point of the second cooling treatment is 45-55℃, for example, it can be 45℃, 48℃, 50℃, 52℃ or 55℃, but is not limited to the listed values, and other values not listed in the value range are also applicable.

[0068] The sintering adopts a sintering mode of air atmosphere in a push plate kiln, which can mass-produce the magnetic core sample and realize low-cost production; at the same time, through the two-stage heat treatment and two-stage cooling treatment mode, the permeability can be significantly improved, the magnet densification is improved, and then the saturation magnetic induction strength Bs of the magnetic core is improved.

[0069] In a third aspect, the application provides an application of the nickel-zinc-copper ferrite material as described in the first aspect, and the nickel-zinc-copper ferrite material is used in a power inductor or a common mode inductor.

[0070] The nickel-zinc-copper ferrite material provided by the application solves the problems of stable permeability at low and high temperatures, low saturation magnetic induction strength and high residual magnetic induction strength, thereby improving the applicability of common mode inductors, laminated magnetic beads / inductors and other power magnetic products, and the nickel-zinc-copper ferrite material can be better applied to the product industries of avionics, automotive electronics, communication electronics and the like.

[0071] Compared with the prior art, the application has the following beneficial effects:

[0072] The present invention can obtain nickel-zinc-copper ferrite materials with high magnetic permeability and Curie temperature by controlling the content range of the main components; in order to ensure high saturation magnetic induction intensity and low specific temperature coefficient characteristics, it is necessary to adjust the overall content of Fe2O3, ZnO, NiO and CuO; by adjusting the auxiliary component Ca 2+ and Bi 3+ The combined substitution of can improve the magnetic permeability and achieve high-frequency charging efficiency; 2+ 、Co 3+ A small amount of substitution can reduce the imaginary part of the magnetic permeability to achieve low loss characteristics; by Ca 2+ 、Co 3+ and Bi 3+ or Zr 4+ The combined substitution of can regulate the saturation magnetic induction intensity to achieve the applicability of devices in extreme environments. The nickel-zinc-copper ferrite material produced by the present invention has high saturation magnetic induction intensity, high magnetic permeability, high Curie temperature, low residual magnetic induction intensity, and low specific temperature coefficient, and can be better applied to power inductors or common-mode inductors. BRIEF DESCRIPTION OF THE DRAWINGS

[0073] Figure 1 This is an SEM image of the nickel-zinc-copper ferrite material provided in Example 1 of the present invention. DETAILED DESCRIPTION

[0074] The technical solution of the present invention is further described below by way of specific embodiments. It should be understood by those skilled in the art that the embodiments are merely to help understand the present invention and should not be regarded as specific limitations of the present invention.

[0075] Example 1

[0076] This embodiment provides a nickel-zinc-copper ferrite material, which includes a main component and an auxiliary component. Based on the total mass percentage of 100wt%, the main component includes: Fe2O3 65.5wt%, NiO 11wt%, ZnO 16.5wt%, and CuO 7wt%; based on the total mass percentage of the main components, the auxiliary components include: Bi2O3 0.5wt%, Co2O3 0.3wt%, CaCO3 0.05wt%, and ZrO2 0.05wt%;

[0077] The total mass percentage of ZnO+CuO in the main component is 23.5wt%; the total mass percentage of Bi2O3+ZrO2 in the auxiliary component is 0.55wt% of the total mass percentage of the main component.

[0078] The preparation method of the nickel-zinc-copper ferrite material comprises the following steps:

[0079] (1) Weighing the main components according to the ratio, and then wet ball milling for 40 minutes, wherein the mass ratio of the main components, zirconium balls and deionized water in the wet ball milling is 1:6:0.8; the obtained ball mill material is subjected to the first spray granulation and then pre-calcined at 850°C for 3 hours to obtain a pre-calcined material;

[0080] (2) weighing auxiliary components according to the proportion, and then grinding the auxiliary components, hydroxy cellulose, sodium stearate, tributyl phosphate, deionized water and the pre-burned material obtained in step (1) at a rotation speed of 200 rpm for 8 minutes and a second grinding at a rotation speed of 300 rpm for 1.5 hours to obtain a grinding material with a median particle size X50 of 0.7 μm and a cumulative percentage of 90% of the particle size X90 of 1.5 μm; the obtained grinding material is subjected to a second spray granulation to obtain particles with an average particle size of 100 μm, and then formed and sintered in a push plate kiln to obtain the nickel-zinc-copper ferrite material;

[0081] The mass ratio of the pre-calcined material, deionized water, hydroxy cellulose, sodium stearate and tributyl phosphate is 100:100:10:1:0.002;

[0082] The sintering includes a first heat treatment, a second heat treatment, a first cooling treatment, and a second cooling treatment performed in sequence; the first heat treatment specifically includes: heating from room temperature to 650°C at a heating rate of 1°C / min in an air atmosphere, and holding the temperature for 5 hours; the second heat treatment specifically includes: continuously heating to 1000°C at a heating rate of 2°C / min, and holding the temperature for 3 hours; the first cooling treatment specifically includes: cooling to 600°C at a cooling rate of 4°C / min in an air atmosphere; the second cooling treatment specifically includes: continuously cooling to 50°C at a cooling rate of 3°C / min;

[0083] The molding includes molding of a standard sample ring blank; the density of the standard sample ring blank is 3.2g / cm 3 , size is H25*15*10mm.

[0084] The SEM image of the nickel-zinc-copper ferrite material prepared in this example is as follows: Figure 1 As shown in the figure, it can be seen that the morphology and particle size are uniform and the grains are relatively dense.

[0085] Example 2

[0086] This embodiment provides a nickel-zinc-copper ferrite material, which includes a main component and an auxiliary component. Based on the total mass percentage of 100wt%, the main component includes: Fe2O3 64.5wt%, NiO 9.5wt%, ZnO 16wt%, and CuO 10wt%; based on the total mass percentage of the main components, the auxiliary components include: Bi2O3 0.3wt%, Co2O3 0.1wt%, CaCO3 0.03wt%, and ZrO2 0.05wt%;

[0087] The total mass percentage of ZnO+CuO in the main component is 26wt%; the total mass percentage of Bi2O3+ZrO2 in the auxiliary component is 0.35wt% of the total mass percentage of the main component.

[0088] The preparation method of the nickel-zinc-copper ferrite material comprises the following steps:

[0089] (1) Weighing the main components according to the ratio, and then wet ball milling for 20 minutes, wherein the mass ratio of the main components, zirconium balls and deionized water in the wet ball milling is 1:4:0.5; the obtained ball mill material is pre-calcined at 780°C for 4 hours after the first spray granulation to obtain a pre-calcined material;

[0090] (2) weighing auxiliary components according to the proportion, and then grinding the auxiliary components, polyvinyl alcohol, triethanolamine, n-octanol, deionized water and the pre-calcined material obtained in step (1) at a rotation speed of 265 rpm for 5 minutes and a second grinding at a rotation speed of 320 rpm for 0.5 hours to obtain a grinding material with a median particle size X50 of 0.5 μm and a cumulative percentage of 90% particle size X90 of 1.25 μm; the obtained grinding material is subjected to a second spray granulation to obtain particles with an average particle size of 30 μm, and then formed and sintered in a push plate kiln to obtain the nickel-zinc-copper ferrite material;

[0091] The mass ratio of the pre-calcined material, deionized water, polyvinyl alcohol, triethanolamine and n-octanol is 100:40:4:0.1:0.001;

[0092] The sintering includes a first heat treatment, a second heat treatment, a first cooling treatment, and a second cooling treatment performed in sequence; the first heat treatment specifically includes: heating from room temperature to 550°C at a heating rate of 0.5°C / min in an air atmosphere, and holding the temperature for 7 hours; the second heat treatment specifically includes: continuing to heat to 950°C at a heating rate of 1°C / min, and holding the temperature for 5 hours; the first cooling treatment specifically includes: cooling to 605°C at a cooling rate of 2°C / min in an air atmosphere; the second cooling treatment specifically includes: continuing to cool to 55°C at a cooling rate of 1°C / min;

[0093] The forming includes a standard sample ring blank forming; the density of the standard sample ring blank is 3.2 g / cm 3 , and the size is H25*15*10 mm.

[0094] Example 3

[0095] The embodiment provides a nickel-zinc-copper ferrite material, the nickel-zinc-copper ferrite material includes a main component and an auxiliary component; the main component includes Fe2O3 66wt%, NiO 12wt%, ZnO 18.5wt%, and CuO 3.5wt% according to 100wt% total mass percentage; the auxiliary component includes Bi2O3 1.45wt%, Co2O3 0.6wt%, CaCO3 0.08wt%, and ZrO2 0.1wt% according to the total mass percentage of the main component;

[0096] The total mass percentage of ZnO+CuO in the main component is 22wt%; the total mass percentage of Bi2O3+ZrO2 in the auxiliary component is 1.55wt% of the total mass percentage of the main component.

[0097] The preparation method of the nickel-zinc-copper ferrite material includes the following steps:

[0098] (1) the main component is weighed according to the proportion, then wet ball milling mixing is carried out for 60min, the mass ratio of the main component, zirconium ball and deionized water in the wet ball milling mixing is 1:8:1.2; the obtained ball mill is pre-fired at 950 DEG C for 2h after first spray granulation, and the pre-fired material is obtained;

[0099] (2) the auxiliary component is weighed according to the proportion, then the auxiliary component, polyvinyl butyral, polyacrylic acid, polyethylene glycol, deionized water and the pre-fired material obtained in step (1) are sequentially first ground at a rotating speed of 145 rpm for 10min and second ground at a rotating speed of 270 rpm for 2h, and the ground material with a median particle size X50 of 0.8um and a particle size X90 of 1.8um with a cumulative percentage of 90% is obtained; the obtained ground material is granulated by second spray granulation to obtain particles with an average particle size of 200um, then forming and sintering in a pusher kiln are carried out, and the nickel-zinc-copper ferrite material is obtained;

[0100] The mass ratio of the pre-fired material, deionized water, polyvinyl butyral, polyacrylic acid and polyethylene glycol is 100:150:20:2:0.0025;

[0101] The sintering includes a first heat treatment, a second heat treatment, a first cooling treatment, and a second cooling treatment performed in sequence; the first heat treatment specifically includes: heating from room temperature to 750°C at a heating rate of 2°C / min in an air atmosphere, and holding the temperature for 2 hours; the second heat treatment specifically includes: continuously heating to 1050°C at a heating rate of 3°C / min, and holding the temperature for 2 hours; the first cooling treatment specifically includes: cooling to 595°C at a cooling rate of 6°C / min in an air atmosphere; the second cooling treatment specifically includes: continuously cooling to 45°C at a cooling rate of 5°C / min;

[0102] The molding includes molding of a standard sample ring blank; the density of the standard sample ring blank is 3.2g / cm 3 , size is H25*15*10mm.

[0103] Example 4

[0104] This embodiment provides a nickel-zinc-copper ferrite material, which differs from Example 1 in that, based on the total mass percentage of 100wt%, the main components are adjusted to: Fe2O3 64.5wt%, NiO 9wt%, ZnO16.5wt%, CuO10wt%, and the total mass percentage of ZnO+CuO is adapted to be 26.5wt%. The rest is the same as Example 1.

[0105] Example 5

[0106] This embodiment provides a nickel-zinc-copper ferrite material, which differs from Example 1 in that, based on the total mass percentage of 100wt%, the main components are adjusted to: Fe2O3 66.5wt%, NiO 12wt%, ZnO 18.5wt%, CuO 3wt%, and the total mass percentage of ZnO+CuO is adapted to be 21.5wt%. The rest is the same as Example 1.

[0107] Example 6

[0108] This embodiment provides a nickel-zinc-copper ferrite material, which differs from Example 1 in that, based on the total mass percentage of the main components, the auxiliary components are adjusted to: Bi2O3 0.3wt%, Co2O3 0.1wt%, CaCO3 0.03wt%, and ZrO2 0.01wt%. The total mass percentage of Bi2O3+ZrO2 is adaptively obtained to be 0.31wt% of the total mass percentage of the main components. The rest is the same as Example 1.

[0109] Example 7

[0110] This embodiment provides a nickel-zinc-copper ferrite material, which differs from Example 1 in that, based on the total mass percentage of the main components, the auxiliary components are adjusted to: Bi2O3 1.5wt%, Co2O3 0.6wt%, CaCO3 0.08wt%, and ZrO2 0.1wt%. The total mass percentage of Bi2O3+ZrO2 is adaptively obtained to be 1.6wt% of the total mass percentage of the main components. The rest is the same as Example 1.

[0111] Example 8

[0112] This embodiment provides a nickel-zinc-copper ferrite material. The preparation method of the nickel-zinc-copper ferrite material differs from that of Example 1 in that the sintering in step (2) is adjusted to a heat treatment and a cooling treatment performed sequentially. The specific steps of the heat treatment include: heating from room temperature to 1000°C at a heating rate of 1.5°C / min in an air atmosphere and keeping the temperature for 8 hours; the specific steps of the cooling treatment include: cooling to 50°C at a cooling rate of 3.5°C / min in an air atmosphere. The rest are the same as in Example 1.

[0113] Comparative Example 1

[0114] This comparative example provides a nickel-zinc-copper ferrite material, which differs from Example 1 in that, based on the total mass percentage as 100wt%, the main components are adjusted to: Fe2O3 64wt%, NiO 8wt%, ZnO20wt%, CuO 8wt%, and the total mass percentage of ZnO+CuO is adapted to be 28wt%. The rest are the same as Example 1.

[0115] Comparative Example 2

[0116] This comparative example provides a nickel-zinc-copper ferrite material, which differs from Example 1 in that, based on the total mass percentage of 100wt%, the main components are adjusted to: Fe2O3 67wt%, NiO 13wt%, ZnO 12wt%, CuO 8wt%, and the total mass percentage of ZnO+CuO is adapted to be 20wt%. The rest are the same as Example 1.

[0117] Comparative Example 3

[0118] This comparative example provides a nickel-zinc-copper ferrite material, which differs from Example 1 in that, based on the total mass percentage of the main components, the auxiliary components are adjusted to: Bi2O3 0.25wt%, Co2O3 0.05wt%, CaCO3 0.02wt%, and ZrO2 0.005wt%, so that the total mass percentage of Bi2O3+ZrO2 is 0.255wt% of the total mass percentage of the main components. The rest are the same as in Example 1.

[0119] Comparative Example 4

[0120] This comparative example provides a nickel-zinc-copper ferrite material, which differs from Example 1 in that, based on the total mass percentage of the main components, the auxiliary components are adjusted to: Bi2O3 1.55wt%, Co2O3 0.65wt%, CaCO3 0.1wt%, and ZrO2 0.15wt%, so that the total mass percentage of Bi2O3+ZrO2 is 1.7wt% of the total mass percentage of the main components. The rest are the same as in Example 1.

[0121] Performance Testing

[0122] The nickel-zinc-copper ferrite materials provided in Examples 1-8 and Comparative Examples 1-4 were tested for inductance using an Agilent E4991, and the real and imaginary parts of the magnetic permeability μi were calculated based on the size coefficient. The Curie temperature Tc and the magnetic permeability in each temperature zone were tested using an LCR magnetic material tester and a high-low temperature controllable oven, and the specific temperature coefficient at each temperature was calculated. The results are shown in Table 1.

[0123] The saturation magnetic induction intensity Bs and residual magnetic induction intensity Br were tested using the SY8218 instrument produced by Iwasaki Corporation of Japan. The results are shown in Table 1.

[0124] Table 1

[0125]

[0126]

[0127] As can be seen from Table 1, the nickel-zinc-copper ferrite material provided by the present invention has the advantages of high Curie temperature, high saturation magnetic induction intensity, low residual magnetic induction intensity, low specific temperature coefficient, etc., and can be better applied to power inductors or common-mode inductors;

[0128] From the comparison between Example 1 and Examples 4-7, it can be seen that when the contents of each main component and auxiliary component are within the specified range, but the total amount of ZnO+CuO or Bi2O3+ZrO2 exceeds the specified range, the overall magnetic properties of the nickel-zinc-copper ferrite material will be reduced. From the comparison between Example 1 and Example 8, it can be seen that sintering as a single heat treatment and cooling treatment will result in lower magnetic permeability compared to two heat treatments and cooling treatments.

[0129] From the comparison between Example 1 and Comparative Examples 1-4, it can be seen that when the content of the main component or the auxiliary component exceeds the specified range, and the total amount of ZnO+CuO or Bi2O3+ZrO2 also exceeds the specified range, the saturation magnetic induction intensity and Curie temperature of the nickel-zinc-copper ferrite material will be greatly reduced, and the residual magnetic induction intensity and the specific temperature coefficient will be increased; In addition, the present invention can uniformly grow FeBi2O4 with a spinel structure by adding Bi2O3. 3+ The K1 value is large, so the content of CoFe2O4 in the composition largely determines the imaginary part of the complex permeability of the nickel-zinc-copper ferrite material. Controlling the CoFe2O4 content within a reasonable range can reduce the loss of the ferrite and ensure high permeability performance at high frequencies. When Bi-Ca and nickel-zinc-copper ferrite materials undergo solid-phase reaction, they mainly grow on the grain boundaries. If the Bi2O3 content in the solution is higher than 1.5wt%, it will cause crystallization on the magnet surface, which will in turn cause the magnetic permeability to decrease and the residual magnetic induction intensity to increase.

[0130] In summary, the present invention can obtain nickel-zinc-copper ferrite materials with high magnetic permeability and Curie temperature by controlling the content range of the main components; in order to ensure high saturation magnetic induction intensity and low specific temperature coefficient characteristics, it is necessary to adjust the overall content of Fe2O3, ZnO, NiO and CuO; by adjusting the auxiliary component Ca 2+ and Bi 3+ The combined substitution of can improve the magnetic permeability and achieve high-frequency charging efficiency; 2+ 、Co 3+ A small amount of substitution can reduce the imaginary part of the magnetic permeability to achieve low loss characteristics; by Ca 2+ 、Co 3+ and Bi 3+ or Zr 4+ The combined substitution of can regulate the saturation magnetic induction intensity to achieve the applicability of devices in extreme environments. The nickel-zinc-copper ferrite material produced by the present invention has high saturation magnetic induction intensity, high magnetic permeability, high Curie temperature, low residual magnetic induction intensity, and low specific temperature coefficient, and can be better applied to power inductors or common-mode inductors.

[0131] The above description is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present invention fall within the protection scope and disclosure scope of the present invention.

Claims

1. A nickel-zinc-copper ferrite material, characterized in that: The nickel-zinc-copper ferrite material includes a main component and an auxiliary component; based on the total mass percentage of 100wt%, the main component includes: Fe2O3 64.5-66.5wt%, NiO 9-12wt%, ZnO 13.5-18.5wt%, CuO 3-10wt%; based on the total mass percentage of the main components, the auxiliary components include: Bi2O3 0.3-1.5wt%, Co2O3 0.1-0.6wt%, CaCO3 0.03-0.08wt%, ZrO2 0.01-0.1wt%; The total mass of Bi2O3+ZrO2 in the auxiliary component is 0.35-1.55wt% of the total mass of the main component.

2. The nickel-zinc-copper ferrite material according to claim 1, characterized in that: The total mass percentage of ZnO+CuO in the main component is 22-26 wt%.

3. A method for preparing the nickel-zinc-copper ferrite material according to claim 1, characterized in that: The preparation method comprises the following steps: (1) Weighing the main components according to the proportion, then wet ball milling and mixing, and pre-calcining the obtained ball milled material after the first spray granulation to obtain a pre-calcined material; (2) weighing auxiliary components according to a ratio, and then sequentially subjecting the auxiliary components, liquid medium, additives and the pre-sintered material obtained in step (1) to a first grinding and a second grinding, and the obtained ground material is subjected to a second spray granulation and then molded and sintered to obtain the nickel-zinc-copper ferrite material.

4. The method for preparing nickel-zinc-copper ferrite material according to claim 3, wherein: The mass ratio of the main component, the ball milling medium and the liquid medium in the wet ball milling mixing of step (1) is 1:(4-8):(0.5-1.2).

5. The method for preparing nickel-zinc-copper ferrite material according to claim 3, wherein: The wet ball milling mixing time in step (1) is 20-60 minutes.

6. The method for preparing nickel-zinc-copper ferrite material according to claim 3, characterized in that: The pre-firing temperature in step (1) is 780-950°C.

7. The method for preparing nickel-zinc-copper ferrite material according to claim 3, wherein: The pre-burning time in step (1) is 2-4 hours.

8. The method for preparing nickel-zinc-copper ferrite material according to claim 3, characterized in that: The additives in step (2) include adhesives, dispersants and defoaming agents.

9. The method for preparing the nickel-zinc-copper ferrite material according to claim 3 or 8, characterized in that: The mass ratio of the pre-burned material, liquid medium, binder, dispersant and defoamer in step (2) is 100:(40-150):(4-20):(0.1-2):(0.001-0.0025).

10. The method for preparing the nickel-zinc-copper ferrite material according to claim 3 or 8, characterized in that: The liquid medium in step (2) includes deionized water.

11. The method for preparing nickel-zinc-copper ferrite material according to claim 3, characterized in that: The rotation speed of the first grinding in step (2) is 145-265 rpm.

12. The method for preparing nickel-zinc-copper ferrite material according to claim 3, characterized in that: The first grinding time in step (2) is 5-10 minutes.

13. The method for preparing nickel-zinc-copper ferrite material according to claim 3, characterized in that: The second grinding speed in step (2) is 270-320 rpm.

14. The method for preparing nickel-zinc-copper ferrite material according to claim 3, characterized in that: The second grinding time in step (2) is 0.5-2h.

15. The method for preparing nickel-zinc-copper ferrite material according to claim 3, characterized in that: The median particle size X50 of the grinding material in step (2) is 0.5-0.8 μm, and the particle size X90 with a cumulative percentage of 90% is 1.25-1.8 μm.

16. The method for preparing nickel-zinc-copper ferrite material according to claim 3, characterized in that: The average particle size of the particles obtained by the second spray granulation in step (2) is 30-200 μm.

17. The method for preparing nickel-zinc-copper ferrite material according to claim 3, characterized in that: The sintering in step (2) is carried out in a push plate kiln.

18. The method for preparing nickel-zinc-copper ferrite material according to claim 3, characterized in that: The sintering in step (2) includes a first heat treatment, a second heat treatment, a first cooling treatment and a second cooling treatment performed in sequence.

19. The method for preparing nickel-zinc-copper ferrite material according to claim 18, characterized in that: The specific steps of the first heat treatment include: heating to 550-750° C. at a heating rate of 0.5-2° C. / min in an air atmosphere, and keeping the temperature for 2-7 hours.

20. The method for preparing nickel-zinc-copper ferrite material according to claim 18, characterized in that: The specific steps of the second heat treatment include: continuing to heat up to 950-1050° C. at a heating rate of 1-3° C. / min, and keeping the temperature for 2-5 hours.

21. The method for preparing nickel-zinc-copper ferrite material according to claim 18, characterized in that: The specific steps of the first cooling treatment include: cooling the temperature to 595-605° C. at a cooling rate of 2-6° C. / min in an air atmosphere.

22. The method for preparing nickel-zinc-copper ferrite material according to claim 18, characterized in that: The specific steps of the second cooling treatment include: continuing to cool to 45-55°C at a cooling rate of 1-5°C / min.

23. Use of the nickel-zinc-copper ferrite material according to claim 1 or 2, characterized in that: The nickel-zinc-copper ferrite material is used in power inductors or common-mode inductors.

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