CN105330276A - Preparation method for zinc-nickel soft magnetic ferrite core material with low thermal expansion coefficient - Google Patents

Abstract

The invention discloses a preparation method for a zinc-nickel soft magnetic ferrite core material with a low thermal expansion coefficient. The oft magnetic ferrite core material is prepared from the raw materials of Fe2O3, NiO, ZnO, Cr2O3, MoO3, Dy2O3, CdO, AlN, B4C, Bi2O3, Co2O3, MnO2, WO3, V2S3, TiC, CaZrO3 and the like. The preparation method comprises the steps of primary batching, primary ball-milling, primary sintering, secondary batching, secondary ball-milling, pressing and molding, secondary sintering and the like. The zinc-nickel soft magnetic ferrite core material prepared by the preparation method is excellent in comprehensive performance, not only has a relatively low thermal expansion coefficient, but also has relatively high magnetic conductivity, saturation flux density, magnetic conductivity and Curie temperature.

Description

A kind of preparation method of low thermal coefficient of expansion Ni-Zn soft magnetic ferrite core material

Technical field

The present invention relates to a kind of preparation method of low thermal coefficient of expansion Ni-Zn soft magnetic ferrite core material, belong to technical field of magnetic materials.

Background technology

Along with the progress of science and technology, soft magnetic ferrite as a kind of important basic function material, extensively

For in the electronic industries such as communication, sensing, audio and video equipment, wave filter, transformer, be answering of soft magnetic ferrite

With opening wide market; Along with the fast development of the electronics and information industry such as communication, computer network, more and more higher to the performance requriements of magnetic ferrite magnetic core material.Magnetic ferrite magnetic core material is in processing and use procedure, and because the height of temperature easily produces heat expansion phenomenon, this just impels magnetic ferrite magnetic core material to lower thermal expansivity future development.Therefore develop a kind of low thermal coefficient of expansion Ni-Zn soft magnetic ferrite core material and have very strong practical significance.

Summary of the invention

The object of this invention is to provide a kind of preparation method of low thermal coefficient of expansion Ni-Zn soft magnetic ferrite core material.

For achieving the above object, the technical solution used in the present invention is as follows:

A preparation method for low thermal coefficient of expansion Ni-Zn soft magnetic ferrite core material, comprises the following steps:

(1) Primary batching system

Take following raw material in molar part to prepare burden: 47.1-53.3molFe ₂o ₃, 18.2-21.5molNiO, 15.4-19.8molZnO, 4.4-6.9molCr ₂o ₃, 2.6-3.7molMoO ₃, 0.6-1.4molDy ₂o ₃, 0.42-0.66molCdO, 0.24-0.39molAlN, 0.14-0.28molB ₄c;

(2) ball millings

Step (1) is taken the raw material obtained mix, add the ethylene being equivalent to mixed powder 1.5-2wt% two amine hydroxybenzene, the sodium lignosulfonate of 0.5-1.5wt% and the beta-glucan cetylate of 0.6-0.9wt%, 7000-9000rpm high speed ball milling 15-20min, dry, pulverize, cross 300-500 mesh sieve;

(3) once sintered

By powder obtained for step (2) at 65%CO ₂820-870 DEG C is warming up to, insulation 3-4h under+35%CO atmosphere, then at 100%N ₂atmosphere borehole cooling, to 440-480 DEG C, is incubated 1-2h, then at 70%Ar+20%N ₂+ 10%H ₂890-930 DEG C is warming up to, insulation 4-5h under atmosphere, then at 60%N ₂+ 40%CO ₂atmosphere borehole cooling is to 600-650 DEG C, and insulation 1-2h, obtains Preburning material;

(4) second batch

Take the Bi being equivalent to Preburning material 2.1-3.4wt% ₂o ₃, 1.6-2.2wt% Co ₂o ₃, 0.8-1.6wt% MnO ₂, 0.4-0.9wt% WO ₃, 0.2-0.4wt% V ₂s ₃, 0.15-0.3wt% the CaZrO of TiC, 0.1-0.2wt% ₃;

(5) secondary ball milling

Step (4) is taken the raw material obtained to mix with the Preburning material that step (3) obtains, then add water to stir and make the suspension that mass concentration is 40-45%, then the poly-naphthalene formaldehyde sulfonate salt, the hydroxypropyl xanthan gum of 0.4-0.8wt%, the peregal O-25 of 0.3-0.6wt% that are equivalent to suspension 1-2wt% is added, 5000-7000rpm high speed ball milling 20-30min, is then spray dried to particulate state powder;

(6) compression moulding

The powder that step (5) obtains is joined in forming mould, adds 30% polyvinyl acetate emulsion being equivalent to powder 8-14wt%, stir, in the pressure forming of 1.0-1.5GPa;

(7) double sintering

Shaping magnetic core blank is carried out double sintering process: first at 50%N ₂be warming up to 430-480 DEG C under+50%Ar atmosphere, insulation 1-2h, then be warming up to 790-840 DEG C, insulation 2-3h; Then at 90%CO ₂+ 10%O ₂1130-1170 DEG C is warming up to, insulation 4-6h under atmosphere, then at 100%N ₂atmosphere borehole cooling, to 720-770 DEG C, is incubated 2-3h, then is cooled to 370-410 DEG C, insulation 0.5-1h; Last at 80%CO ₂+ 10%N ₂+ 10%O ₂be warming up to 1080-1140 DEG C under atmosphere, insulation 3-5h, then at 100%Ar atmosphere borehole cooling to 580-640 DEG C, insulation 1-2h, is quickly cooled to normal temperature afterwards.

Beneficial effect of the present invention:

The present invention adopts and adds appropriate CdO, B under the prerequisite not affecting magnetic property ₄c, V ₂s ₃, AlN, TiC, CaZrO ₃improve the thermostability of Ni-Zn soft magnetic ferrite core material Deng raw material, reduce its thermal expansivity.The Ni-Zn soft magnetic ferrite core material excellent combination property that the present invention obtains, not only has lower thermal expansivity, also has higher magnetic permeability and saturation magnetic flux density, magnetic permeability and Curie temperature.

Embodiment

A preparation method for low thermal coefficient of expansion Ni-Zn soft magnetic ferrite core material, comprises the following steps:

(1) Primary batching system

Take following raw material in molar part to prepare burden: 50.6molFe ₂o ₃, 19.7molNiO, 17.4molZnO, 5.8molCr ₂o ₃, 3.1molMoO ₃, 0.89molDy ₂o ₃, 0.54molCdO, 0.32molAlN, 0.22molB ₄c;

(2) ball millings

Step (1) is taken the raw material obtained mix, add the ethylene being equivalent to mixed powder 1.8wt% two amine hydroxybenzene, the sodium lignosulfonate of 0.9wt% and the beta-glucan cetylate of 0.7wt%, 8000rpm high speed ball milling 16min, dries, pulverize, cross 400 mesh sieves;

(3) once sintered

By powder obtained for step (2) at 65%CO ₂850 DEG C are warming up to, insulation 3.5h under+35%CO atmosphere, then at 100%N ₂atmosphere borehole cooling to 460 DEG C, insulation 1.5h, then at 70%Ar+20%N ₂+ 10%H ₂920 DEG C are warming up to, insulation 5h under atmosphere, then at 60%N ₂+ 40%CO ₂atmosphere borehole cooling to 620 DEG C, insulation 1.5h, obtains Preburning material;

(4) second batch

Take the Bi being equivalent to Preburning material 2.9wt% ₂o ₃, 1.8wt% Co ₂o ₃, 1.1wt% MnO ₂, 0.6wt% WO ₃, 03wt% V ₂s ₃, 0.25wt% the CaZrO of TiC, 0.15wt% ₃;

(5) secondary ball milling

Step (4) is taken the raw material obtained to mix with the Preburning material that step (3) obtains, then add water to stir and make the suspension that mass concentration is 42%, then the poly-naphthalene formaldehyde sulfonate salt, the hydroxypropyl xanthan gum of 0.6wt%, the peregal O-25 of 0.4wt% that are equivalent to suspension 1.5wt% is added, 6000rpm high speed ball milling 25min, is then spray dried to particulate state powder;

(6) compression moulding

The powder that step (5) obtains is joined in forming mould, adds 30% polyvinyl acetate emulsion being equivalent to powder 12wt%, stir, in the pressure forming of 1.3GPa;

(7) double sintering

Shaping magnetic core blank is carried out double sintering process: first at 50%N ₂be warming up to 470 DEG C under+50%Ar atmosphere, insulation 1.5h, then be warming up to 820 DEG C, insulation 3h; Then at 90%CO ₂+ 10%O ₂1150 DEG C are warming up to, insulation 5h under atmosphere, then at 100%N ₂atmosphere borehole cooling to 760 DEG C, insulation 2.5h, then be cooled to 390 DEG C, insulation 0.5h; Last at 80%CO ₂+ 10%N ₂+ 10%O ₂be warming up to 1120 DEG C under atmosphere, insulation 4h, then at 100%Ar atmosphere borehole cooling to 610 DEG C, insulation 1.5h, is quickly cooled to normal temperature afterwards.

The performance test results of the magnetic ferrite magnetic core material that above-described embodiment obtains is as shown in the table

	Test item	Detected result
			1	Thermal expansivity (/K)	3.6×10 -6
2	Initial permeability μ i	14000
			3	Maximum permeability μ max	22000
4	Saturation magnetic flux density B s（mT）	405
			5	Coercive force H c（A/m）	2.7
6	Curie temperature T c（℃）	260
			7	Power loss P cw，100kHz，200mT，100℃（kW·m -3）	140

Claims (1)

1. a preparation method for low thermal coefficient of expansion Ni-Zn soft magnetic ferrite core material, is characterized in that comprising the following steps:

(1) Primary batching system

Take following raw material in molar part to prepare burden: 47.1-53.3molFe ₂o ₃, 18.2-21.5molNiO, 15.4-19.8molZnO, 4.4-6.9molCr ₂o ₃, 2.6-3.7molMoO ₃, 0.6-1.4molDy ₂o ₃, 0.42-0.66molCdO, 0.24-0.39molAlN, 0.14-0.28molB ₄c;

(2) ball millings

Step (1) is taken the raw material obtained mix, add the ethylene being equivalent to mixed powder 1.5-2wt% two amine hydroxybenzene, the sodium lignosulfonate of 0.5-1.5wt% and the beta-glucan cetylate of 0.6-0.9wt%, 7000-9000rpm high speed ball milling 15-20min, dry, pulverize, cross 300-500 mesh sieve;

Once sintered

By powder obtained for step (2) at 65%CO ₂820-870 DEG C is warming up to, insulation 3-4h under+35%CO atmosphere, then at 100%N ₂atmosphere borehole cooling, to 440-480 DEG C, is incubated 1-2h, then at 70%Ar+20%N ₂+ 10%H ₂890-930 DEG C is warming up to, insulation 4-5h under atmosphere, then at 60%N ₂+ 40%CO ₂atmosphere borehole cooling is to 600-650 DEG C, and insulation 1-2h, obtains Preburning material;

Second batch

Take the Bi being equivalent to Preburning material 2.1-3.4wt% ₂o ₃, 1.6-2.2wt% Co ₂o ₃, 0.8-1.6wt% MnO ₂, 0.4-0.9wt% WO ₃, 0.2-0.4wt% V ₂s ₃, 0.15-0.3wt% the CaZrO of TiC, 0.1-0.2wt% ₃;

Secondary ball milling

Step (4) is taken the raw material obtained to mix with the Preburning material that step (3) obtains, then add water to stir and make the suspension that mass concentration is 40-45%, then the poly-naphthalene formaldehyde sulfonate salt, the hydroxypropyl xanthan gum of 0.4-0.8wt%, the peregal O-25 of 0.3-0.6wt% that are equivalent to suspension 1-2wt% is added, 5000-7000rpm high speed ball milling 20-30min, is then spray dried to particulate state powder;

Compression moulding

The powder that step (5) obtains is joined in forming mould, adds 30% polyvinyl acetate emulsion being equivalent to powder 8-14wt%, stir, in the pressure forming of 1.0-1.5GPa;

(7) double sintering

Shaping magnetic core blank is carried out double sintering process: first at 50%N ₂be warming up to 430-480 DEG C under+50%Ar atmosphere, insulation 1-2h, then be warming up to 790-840 DEG C, insulation 2-3h; Then at 90%CO ₂+ 10%O ₂1130-1170 DEG C is warming up to, insulation 4-6h under atmosphere, then at 100%N ₂atmosphere borehole cooling, to 720-770 DEG C, is incubated 2-3h, then is cooled to 370-410 DEG C, insulation 0.5-1h; Last at 80%CO ₂+ 10%N ₂+ 10%O ₂be warming up to 1080-1140 DEG C under atmosphere, insulation 3-5h, then at 100%Ar atmosphere borehole cooling to 580-640 DEG C, insulation 1-2h, is quickly cooled to normal temperature afterwards.