CN104045334A - Rear-earth ferrite magnetic core material used for transformer - Google Patents

Abstract

The invention discloses a rear-earth ferrite magnetic core material used for a transformer. The rear-earth ferrite magnetic core material comprises main ingredients and additives, wherein the main ingredients comprise the following components in molar ratio: 61.4-70 mol of Fe2O3, 16.7-20 mol of manganese oxide, 10-14.2 mol of zinc oxide, 1-2 mol of copper oxide, 0.4-0.6 mol of calcium sulfate and 0.01-0.02 mol of rear-earth composite magnetic powder; the additives comprise the following components in proportion by weight (based on the ferrite magnetic core material): 40-50 ppm of chromic oxide and 800-1000 ppm of zinc borate. The rear-earth composite magnetic powder added in the ferrite magnetic core material disclosed by the invention is high in magnetic energy product, stable in magnetism and simple in preparation method; a finished product has characteristics of high crystal boundary resistivity, low porosity, great and uniform crystalline grain.

Description

A kind of rare-earth ferrite core material for transformer

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Technical field

The present invention relates generally to oxidate magnetic material and manufactures field, relates in particular to a kind of rare-earth ferrite core material for transformer.

Background technology

Along with the communication technology and the digitized development of electronic product; soft magnetic ferrite and element have been proposed to new requirement; high-performance high magnetic permeability magnetic core is widely used in each type telecommunications and information basic material, as the fields such as common-mode filter, saturation inductance, current transformer, earth leakage protective device, insulating transformer, signal and pulse transformer are widely applied.Telecommunications industry needs FERRITE CORE to have low core loss and high magnetic permeability now, and to meet microminiaturization and the high efficiency requirement of present electrical equipment, existing magnetic core is difficult to meet above-mentioned requirements;

Its magnetic energy product of the permanent magnet material that rare earth makes can reach 150 times of carbon steel, 3～5 times of Al-Ni-Co permanent magnet material, 8～10 times of permanent-magnet ferrite, and temperature factor is low, magnetic stability, coercive force is up to 800 kilo-ampere/rice.Be mainly used in the magnetic system of low speed torque electric motor, actuating motor, sensor, magnetic bearing etc.Nd-Fe-Bo permanent magnet material is third generation rare earth permanent-magnetic material, and its remanent magnetism, coercive force and maximum magnetic energy product are higher than the former, non-friable, has good mechanical property, and alloy density is low, is conducive to lightness, slimming, the small-sized and subminiaturization of magnetics.

Summary of the invention

The object of the invention is exactly in order to make up the defect of prior art, and a kind of rare-earth ferrite core material for transformer is provided.

The present invention is achieved by the following technical solutions:

A kind of rare-earth ferrite core material for transformer, it comprises major ingredient and additive, and described major ingredient comprises according to mol ratio: the rare earth compounded magnetic conductive powder of the calcium sulfate of the manganese oxide of the Fe2O3 of 61.4-70 mol, 16.7-20 mol, the zinc oxide of 10-14.2 mol, the cupric oxide of 1-2mol, 0.4-0.6 mol, 0.01-0.02 mol; Additive comprises according to the weight ratio meter that accounts for described ferrite magnetic core material: the chromic oxide of 40-50ppm, the zinc borate of 800-1000ppm;

The preparation of described rare earth compounded magnetic conductive powder comprises the following steps:

The preparation of premixed liquid:

Described premixed liquid is comprised of the raw material of following weight parts: gelatine 7-10, ferric oxide 40-50, oleic acid 2-3, fatty alcohol-polyoxyethylene ether 1-2;

Gelatine is joined in 20-30 times of water, dispersed with stirring 2-3 hour at 70-80 ℃, it is to add after 40-60 μ m that ferric oxide is ground to fineness, adds oleic acid, fatty alcohol-polyoxyethylene ether, 600-800 rev/min of dispersed with stirring 20-30 minute, obtains premixed liquid;

The TriMethylolPropane(TMP) that is 1-2:5-7:100 by mass ratio, stearic acid, Neodymium trioxide mix, at 58-65 ℃, be uniformly mixed 30-40 minute, adding concentration is the acetic acid of 10-20%, 70-100 rev/min of dispersed with stirring 4-6 minute, add Neutral ammonium fluoride, be uniformly mixed 20-30 minute, add premixed liquid, 400-500 rev/min of dispersed with stirring 1-2 hour, dry 20-30 minute at 80-100 ℃, send into sintering oven, sintering 4-6 hour at 300-350 ℃, obtains described rare earth compounded magnetic conductive powder;

The mol ratio of described Neodymium trioxide, acetic acid, Neutral ammonium fluoride is 2-3:6-7:1-2;

Described ferric oxide and the mass ratio of Neodymium trioxide are 10-20:1.

A preparation method for the rare-earth ferrite core material of transformer, comprises the following steps:

(1) above-mentioned major ingredient is sent into mixing tank, 2500-3000 rev/min is stirred mixed 2-4 hour, sends into grinding pot, being ground to fineness is 50-70 μ m, add the water of major ingredient weight 20-30%, the catechol of the aluminium triphosphate of 2-3%, 1-2%, high-speed stirring is mixed, and obtains slurries;

(2) additive is sent into grinding pot, add the Magnesium Stearate of weight of additive 1-2%, being ground to fineness is 60-100 μ m;

(3) each raw material after above-mentioned processing is mixed, stir, spraying is dry, is pressed into base, and sintering obtains the described rare-earth ferrite core material for transformer.

Advantage of the present invention is:

The rare earth compounded magnetic conductive powder magnetic energy product that ferrite magnetic core material of the present invention adds is high, magnetic stability, and preparation method is simple, and it is high that finished product has grain boundary resistance rate, and void content is low, mechanical property is strong, and crystal grain is feature greatly and uniformly.

Embodiment

Embodiment 1

A kind of rare-earth ferrite core material for transformer, it is characterized in that it comprises major ingredient and additive, described major ingredient comprises according to mol ratio: the rare earth compounded magnetic conductive powder of the calcium sulfate of the Fe2O3 of 61.4 mol, the manganese oxide of 16.7mol, the zinc oxide of 14.2 mol, the cupric oxide of 1mol, 0.6 mol, 0.02 mol; Additive comprises according to the weight ratio meter that accounts for described ferrite magnetic core material: the chromic oxide of 50ppm, the zinc borate of 1000ppm;

The preparation of described rare earth compounded magnetic conductive powder comprises the following steps:

The preparation of premixed liquid:

Described premixed liquid is comprised of the raw material of following weight parts: gelatine 10, ferric oxide 50, oleic acid 3, fatty alcohol-polyoxyethylene ether 2;

Gelatine is joined in 30 times of water, and at 80 ℃, dispersed with stirring is 2 hours, and it is to add after 60 μ m that ferric oxide is ground to fineness, adds oleic acid, fatty alcohol-polyoxyethylene ether, and 800 revs/min of dispersed with stirring 30 minutes, obtain premixed liquid;

The TriMethylolPropane(TMP) that is 2:7:100 by mass ratio, stearic acid, Neodymium trioxide mix, at 65 ℃, be uniformly mixed 40 minutes, adding concentration is 20% acetic acid, 100 revs/min of dispersed with stirring 6 minutes, add Neutral ammonium fluoride, be uniformly mixed 30 minutes, add premixed liquid, 500 revs/min of dispersed with stirring 2 hours, at 100 ℃, be dried 20 minutes, send into sintering oven, sintering is 4 hours at 350 ℃, obtains described rare earth compounded magnetic conductive powder;

The mol ratio of described Neodymium trioxide, acetic acid, Neutral ammonium fluoride is 2:7:2;

Described ferric oxide and the mass ratio of Neodymium trioxide are 20:1.

A preparation method for the rare-earth ferrite core material of transformer, comprises the following steps:

(1) above-mentioned major ingredient is sent into mixing tank, 3000 revs/min are stirred mixed 2 hours, send into grinding pot, and being ground to fineness is 70 μ m, adds the water of major ingredient weight 30%, 2% aluminium triphosphate, 1% catechol, and high-speed stirring is mixed, and obtains slurries;

(2) additive is sent into grinding pot, add the Magnesium Stearate of weight of additive 1-2%, being ground to fineness is 100 μ m;

(3) each raw material after above-mentioned processing is mixed, stir, spraying is dry, is pressed into base, and sintering obtains the described rare-earth ferrite core material for transformer.

Through detection, the basic mechanical design feature index that the product of above-described embodiment 1 gained reaches:

The initial permeability of magnetic core of the present invention is greater than 2700 μ i;

Maximum magnetic flux core loss (100Kc, 200mT) unit: KW/m ³: 415 (100 ± 2 ℃);

Curie temperature is higher than 240 ℃.

Claims (2)

1. the rare-earth ferrite core material for transformer, it is characterized in that it comprises major ingredient and additive, described major ingredient comprises according to mol ratio: the rare earth compounded magnetic conductive powder of the calcium sulfate of the manganese oxide of the Fe2O3 of 61.4-70 mol, 16.7-20 mol, the zinc oxide of 10-14.2 mol, the cupric oxide of 1-2mol, 0.4-0.6 mol, 0.01-0.02 mol; Additive comprises according to the weight ratio meter that accounts for described ferrite magnetic core material: the chromic oxide of 40-50ppm, the zinc borate of 800-1000ppm;

The preparation of described rare earth compounded magnetic conductive powder comprises the following steps:

The preparation of premixed liquid:

Described premixed liquid is comprised of the raw material of following weight parts: gelatine 7-10, ferric oxide 40-50, oleic acid 2-3, fatty alcohol-polyoxyethylene ether 1-2;

Gelatine is joined in 20-30 times of water, dispersed with stirring 2-3 hour at 70-80 ℃, it is to add after 40-60 μ m that ferric oxide is ground to fineness, adds oleic acid, fatty alcohol-polyoxyethylene ether, 600-800 rev/min of dispersed with stirring 20-30 minute, obtains premixed liquid;

The TriMethylolPropane(TMP) that is 1-2:5-7:100 by mass ratio, stearic acid, Neodymium trioxide mix, at 58-65 ℃, be uniformly mixed 30-40 minute, adding concentration is the acetic acid of 10-20%, 70-100 rev/min of dispersed with stirring 4-6 minute, add Neutral ammonium fluoride, be uniformly mixed 20-30 minute, add premixed liquid, 400-500 rev/min of dispersed with stirring 1-2 hour, dry 20-30 minute at 80-100 ℃, send into sintering oven, sintering 4-6 hour at 300-350 ℃, obtains described rare earth compounded magnetic conductive powder;

The mol ratio of described Neodymium trioxide, acetic acid, Neutral ammonium fluoride is 2-3:6-7:1-2;

Described ferric oxide and the mass ratio of Neodymium trioxide are 10-20:1.

2. a preparation method for the rare-earth ferrite core material for transformer as claimed in claim 1, is characterized in that comprising the following steps:

(1) above-mentioned major ingredient is sent into mixing tank, 2500-3000 rev/min is stirred mixed 2-4 hour, sends into grinding pot, being ground to fineness is 50-70 μ m, add the water of major ingredient weight 20-30%, the catechol of the aluminium triphosphate of 2-3%, 1-2%, high-speed stirring is mixed, and obtains slurries;

(2) additive is sent into grinding pot, add the Magnesium Stearate of weight of additive 1-2%, being ground to fineness is 60-100 μ m;

(3) each raw material after above-mentioned processing is mixed, stir, spraying is dry, is pressed into base, and sintering obtains the described rare-earth ferrite core material for transformer.