CN104064311A - Silicon carbide-based ferrite magnetic core material for transformer - Google Patents

Abstract

The invention discloses a silicon carbide-based ferrite magnetic core material for a transformer. The material comprises major ingredients and additives, wherein the major ingredients comprise 58.7 to 65 moles of Fe2O3, 15.1 to 19 moles of manganese oxide, 10.2 to 14 moles of zinc oxide, 4 to 5.6 moles of ferroferric oxide, 0.1 to 0.2 mole of calcium sulfate, 0.1 to 0.2 mole of magnesium dihydrogen phosphate and 0.01 to 0.02 mole of rare earth composite magnetic-conducting powder according to a molar ratio; the additives comprise 80 to 100 parts per million of molybdenum oxide and 40 to 50 parts per million of zirconium oxide based on the weight of the ferrite magnetic core material. The rare earth composite magnetic-conducting powder added to the ferrite magnetic core material has a magnetic energy product and stable magnetism, a preparation method is simple, and a finished product has the characteristics of high grain boundary resistivity, low porosity and large and uniform crystal grain sizes.

Description

A kind of silicon carbide-based ferrite magnetic core material for transformer

Technical field

The present invention relates generally to oxidate magnetic material and manufactures field, relates in particular to a kind of silicon carbide-based ferrite magnetic 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 stock, as the fields such as common-mode filter, pulsactor, 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 electric equipment, existing magnetic core is difficult to meet above-mentioned requirements;

Its magnetic energy product of the permanent magnetic 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 coefficient is low, magnetic stability, coercive force is up to 800 kilo-ampere/rice.Be mainly used in the magnetic system of low speed torque motor, actuating motor, transducer, 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 performance, and alloy density is low, is conducive to lightness, slimming, the small-sized and subminaturization of magnetic element.

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 silicon carbide-based ferrite magnetic core material for transformer is provided.

The present invention is achieved by the following technical solutions:

A kind of silicon carbide-based ferrite magnetic 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 magnesium dihydrogen phosphate of the manganese oxide of the Fe2O3 of 58.7-65 mol, 15.1-19 mol, the zinc oxide of 10.2-14 mol, the calcium sulfate of the tri-iron tetroxide of 4-5.6mol, 0.1-0.2mol, 0.1-0.2 mol, 0.01-0.02 mol; Additive comprises according to the weight ratio meter that accounts for described ferrite magnetic core material: the molybdenum oxide of 80-100ppm, the zirconia of 40-50ppm;

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:

Carborundum 80-90, APP 3-4, alkenyl succinic acid ester 2-3, glycerin monostearate 0.5-1, deionized water 300-400;

By carborundum and APP mixing and ball milling to fineness, be 40-100 μ m, add alkenyl succinic acid ester, be uniformly mixed 10-15 minute;

Each raw material after above-mentioned processing is mixed, and 400-500 rev/min of dispersed with stirring 12-20 minute, obtains premixed liquid;

The trimethylolpropane that is 1-2:5-7:100 by mass ratio, stearic acid, neodymia 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 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 furnace, sintering 4-6 hour at 300-350 ℃, obtains described rare earth compounded magnetic conductive powder;

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

Described carborundum and the mass ratio of neodymia are 60-80:1.

A preparation method for the silicon carbide-based ferrite magnetic core material of transformer, comprises the following steps:

(1) each raw material except rare earth compounded magnetic conductive powder in above-mentioned major ingredient is sent into blending tank, 2500-3000 rev/min is stirred mixed 2-3 hour, send into rotary furnace pre-burning, pre-burning 2-3 hour at 350-400 ℃, send into grinding pot, add rare earth compounded magnetic conductive powder, being ground to fineness is 60-80 μ m;

(2) additive is sent into grinding pot, add the polyacrylamide of weight of additive 0.6-1%, being ground to fineness is 50-70 μ m;

(3) each raw material after above-mentioned processing is mixed, add the water of compound weight 20-30%, the stearic acid of the ammonium superphosphate of 1-2%, 2-3% is uniformly mixed 20-30 minute at 60-70 ℃;

(4) spraying is dry, is pressed into base, and sintering obtains the described silicon carbide-based ferrite magnetic 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 the porosity is low, mechanical performance is strong, and crystal grain is feature greatly and uniformly.

Embodiment

Embodiment 1

A kind of silicon carbide-based ferrite magnetic 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 magnesium dihydrogen phosphate of the Fe2O3 of 58.7mol, the manganese oxide of 15.1mol, the zinc oxide of 10.2mol, the calcium sulfate of the tri-iron tetroxide of 5.6mol, 0.2mol, 0.2 mol, 0.02 mol; Additive comprises according to the weight ratio meter that accounts for described ferrite magnetic core material: the molybdenum oxide of 100ppm, the zirconia of 50ppm;

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:

Carborundum 90, APP 3, alkenyl succinic acid ester 3, glycerin monostearate 0.5, deionized water 400;

By carborundum and APP mixing and ball milling to fineness, be 100 μ m, add alkenyl succinic acid ester, be uniformly mixed 10-15 minute;

Each raw material after above-mentioned processing is mixed, and 500 revs/min of dispersed with stirring 20 minutes, obtain premixed liquid;

The trimethylolpropane that is 1:5:100 by mass ratio, stearic acid, neodymia mix, at 65 ℃, be uniformly mixed 40 minutes, adding concentration is 20% acetic acid, 100 revs/min of dispersed with stirring 6 minutes, add ammonium fluoride, be uniformly mixed 30 minutes, add premixed liquid, 500 revs/min of dispersed with stirring 1 hour, at 100 ℃, be dried 30 minutes, send into sintering furnace, sintering is 6 hours at 350 ℃, obtains described rare earth compounded magnetic conductive powder;

The mol ratio of described neodymia, acetic acid, ammonium fluoride is 2:6:1;

Described carborundum and the mass ratio of neodymia are 80:1.

A preparation method for the silicon carbide-based ferrite magnetic core material of transformer, comprises the following steps:

(1) each raw material except rare earth compounded magnetic conductive powder in above-mentioned major ingredient is sent into blending tank, 3000 revs/min are stirred mixed 2-3 hour, send into rotary furnace pre-burning, at 400 ℃, pre-burning is 3 hours, send into grinding pot, add rare earth compounded magnetic conductive powder, being ground to fineness is 80 μ m;

(2) additive is sent into grinding pot, add the polyacrylamide of weight of additive 0.6%, being ground to fineness is 70 μ m;

(3) each raw material after above-mentioned processing is mixed, add the water of compound weight 20%, 2% ammonium superphosphate, 2% stearic acid, at 70 ℃, be uniformly mixed 30 minutes;

(4) spraying is dry, is pressed into base, and sintering obtains the described silicon carbide-based ferrite magnetic 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: 385 (100 ± 2 ℃);

Curie temperature is higher than 240 ℃.

Claims (2)

1. the silicon carbide-based ferrite magnetic 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 magnesium dihydrogen phosphate of the manganese oxide of the Fe2O3 of 58.7-65 mol, 15.1-19 mol, the zinc oxide of 10.2-14 mol, the calcium sulfate of the tri-iron tetroxide of 4-5.6mol, 0.1-0.2mol, 0.1-0.2 mol, 0.01-0.02 mol; Additive comprises according to the weight ratio meter that accounts for described ferrite magnetic core material: the molybdenum oxide of 80-100ppm, the zirconia of 40-50ppm;

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:

Carborundum 80-90, APP 3-4, alkenyl succinic acid ester 2-3, glycerin monostearate 0.5-1, deionized water 300-400;

By carborundum and APP mixing and ball milling to fineness, be 40-100 μ m, add alkenyl succinic acid ester, be uniformly mixed 10-15 minute;

Each raw material after above-mentioned processing is mixed, and 400-500 rev/min of dispersed with stirring 12-20 minute, obtains premixed liquid;

The trimethylolpropane that is 1-2:5-7:100 by mass ratio, stearic acid, neodymia 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 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 furnace, sintering 4-6 hour at 300-350 ℃, obtains described rare earth compounded magnetic conductive powder;

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

Described carborundum and the mass ratio of neodymia are 60-80:1.

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

(1) each raw material except rare earth compounded magnetic conductive powder in above-mentioned major ingredient is sent into blending tank, 2500-3000 rev/min is stirred mixed 2-3 hour, send into rotary furnace pre-burning, pre-burning 2-3 hour at 350-400 ℃, send into grinding pot, add rare earth compounded magnetic conductive powder, being ground to fineness is 60-80 μ m;

(2) additive is sent into grinding pot, add the polyacrylamide of weight of additive 0.6-1%, being ground to fineness is 50-70 μ m;

(3) each raw material after above-mentioned processing is mixed, add the water of compound weight 20-30%, the stearic acid of the ammonium superphosphate of 1-2%, 2-3% is uniformly mixed 20-30 minute at 60-70 ℃;

(4) spraying is dry, is pressed into base, and sintering obtains the described silicon carbide-based ferrite magnetic core material for transformer.