CN101202138A - Permanent ferrite magnetic tile and preparation method thereof - Google Patents
Permanent ferrite magnetic tile and preparation method thereof Download PDFInfo
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- CN101202138A CN101202138A CNA2007101341145A CN200710134114A CN101202138A CN 101202138 A CN101202138 A CN 101202138A CN A2007101341145 A CNA2007101341145 A CN A2007101341145A CN 200710134114 A CN200710134114 A CN 200710134114A CN 101202138 A CN101202138 A CN 101202138A
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Abstract
The invention relates to a permanent ferrite magnetic arc and the manufacturing method thereof, belonging to a manufacturing field of a motor permanent ferrite. Weight proportions of main material components and additive components are as the following: main materials: 8.7 to 9.0 percent of strontium oxide; 86 to 87 percent of iron oxide red; additives: 0.6 to 1.0 percent of calcium carbonate; 0.6 to 1.0 percent of aluminum oxide; 0.4 to 0.8 percent of chrome oxide; 0.3 to 0.6 percent of boric acid; 0.3 to 0.5 percent of silicon oxide; 0.2 to 0.4 percent of cobalt oxide; 0.2 to 0.4 percent of lanthanum oxide and 0.1 to 0.3 percent of silicate fiber. The invention is provided with high surplus magnetic induction strength and high intrinsic coercivity so as to enhance a mechanical strength of the magnetic arc.
Description
Technical field
The present invention relates to a kind of permanent ferrite magnetic tile and preparation method thereof, belong to the motor permanent-magnet ferrite and make the field.
Background technology
Permanent-magnet ferrite anisotropy sintering magnetic shoe is at numerous permanent magnetic materials, becomes the permanent magnetic material that use amount is the most extensive in the world, output is maximum at present with cost performance the best, is widely used in big as the motor in exciter, pilot exciter, the aircraft; Little floppy drive and hard disk driver motor as using in the computer, the motor in the information products, electric bicycle motor, electric motor of automobile, and many motors require and can work under the condition that high low temperature, vibrations, impact and dc electromagnetic field disturb.Because permanent ferrite magnetic tile is a critical component in the DC motor, therefore, higher requirement has been proposed for the magnetic property of magnetic shoe.When how to make residual magnetic flux density Br 〉=4300 Gs, HCJ Hcj 〉=398kA/m is the bottleneck that is difficult to break through on the permanent-magnet ferrite industry material property always.
At present, the permanent magnetic tile that all belongs to medium class that permanent-magnet ferrite enterprise produces, its technical parameter level is mostly at Br:370~380mT, Hcb:262~270kA/m, Hcj:350~360kA/m, (BH) max:23.8~25kJ/m
3This magnetic shoe is contained in anti-high and low-temp poor performance in the motor because Br is not high, so the demagnetization rate reach more than 20%, have in addition reach 30%.Motor is in running, permanent magnetic tile periodically constantly is subjected to the effect of demagnetizing field, the energy loss of motor each several part finally all becomes heat simultaneously, temperature when making motor reach heat balance is very high, and the demagnetization rate of magneto all requires below 10% now, and has the performance of high-and low-temperature resistance (40~140 ℃).Must have higher HCJ Hcj and critical magnetic field H so be used for the permanent magnetic tile of direct current machine
kSimultaneously, motor bears very big centrifugal force in running, and promptly tensile stress also easily causes the magnetic shoe cracking.
Summary of the invention
The objective of the invention is when having high residual magnetic flux density, to have high HCJ again, can improve the permanent ferrite magnetic tile and preparation method thereof of the mechanical strength of magnetic shoe for a kind of.
The present invention is that the technical scheme that achieves the above object is: a kind of permanent ferrite magnetic tile, comprise major ingredient and additive, and it is characterized in that: described major ingredient and components of additives and percentage by weight thereof are as follows:
Major ingredient: strontium oxide strontia 8.7%~9.0%
Iron oxide red 86%~87%
Additive: calcium carbonate 0.6%~1.0%
Alundum (Al 0.6%~1.0%
Chrome green 0.4%~0.8%
Boric acid 0.3%~0.6%
Silicon dioxide 0.3%~0.5%
Cobaltosic oxide 0.2%~0.4%
Lanthanum sesquioxide 0.2%~0.4%
Silicate fiber 0.1%~0.3%.
The manufacture method of permanent ferrite magnetic tile of the present invention is carried out according to the following steps,
(1), batching: by weight percentage with 8.7%~9.0% strontium oxide strontia, 86%~87% iron oxide red and 0.2%~0.5% calcium carbonate mix forms the pre-burning material;
(2), pre-burning pellet mill: pre-imitation frosted glass is put into the ball mill ball milling, pre-imitation frosted glass is evenly mixed, the particle≤2 μ m of pre-imitation frosted glass;
(3), clamp dog, pre-burning: pre-imitation frosted glass is added water stir back briquet type, put into stove and fire under 1250 ℃-1280 ℃ temperature, the time is controlled at 4h~6h, fltting speed 38~45min/ plate;
(4), pulverize: the piece material of sinter molding is pulverized the particle of powder≤3.5 μ m;
(5), batch mixing: in compound, add 0.3%~0.5% calcium carbonate, 0.6%~1.0% alundum (Al, 0.4%~0.8% chrome green, 0.3%~0.6% boric acid, 0.3%~0.5% silicon dioxide, 0.2%~0.4% cobaltosic oxide and 0.2%~0.4% lanthanum sesquioxide by weight percentage, and mix;
(6), secondary ball milling: earlier batch mixing is carried out thick ball milling in ball mill, the slip granularity is controlled at 1.0 μ m~1.3 μ m, slip is squeezed in the fine grinding ball mill again, and add 0.1%~0.3% silicate fiber and dispersant and grinding aid and carry out ball milling, by ratio of weight and the number of copies, powder: dispersant: the grinding aid ratio is 1: 0.003~0.005: 0.001~0.003, and the pH value of slip is controlled between 7~9, and the slip granularity is controlled at 0.75 μ m~0.85 μ m;
(7), slip precipitation: the slip precipitation is dewatered, and the slip moisture content is controlled at 35%~45%;
(8), the compacting green compact: slip is injected mould, under the pressure of 15Mp~18Mpa, makes green compact, magnetize with 5~7 Wan An circle D.C. magnetic fields, the pulsed magnetic field of 9~10 Wan An circles that superpose simultaneously, the degree of orientation 〉=98%, green density is at 3.2g/cm
3~3.4g/cm
3
(9), sintering: green compact are put into the inherent 1130-1200 ℃ of sintering temperature of stove, and the time is controlled at 1.5h~2.5h, and fltting speed 12~18min/ plate is incubated 1h~2h, adopts anxious quenching during cooling before 800 ℃, comes out of the stove;
(10), mill processing: be ground to required physical dimension, make finished product.
The present invention adopts the advantage after the technique scheme to be:
1, the present invention adopts the moderate major ingredient of purity, and select properly mixed additive for use, and be equipped with special manufacture craft, control the micro-structural of crystal by the compound replacement of ion, to improve the solid solution capacity of cobalt ions and lanthanum ion, improve the combination property of magnetic shoe, as saturation magnetization, remanent magnetization, magnetocrystalline anisotropy constant etc., because the magnetic shoe internal structure more becomes even, organize densification more, can reach high-orientation, green density is greater than 3.2g/cm
3, density reaches 5.1g/cm behind the magnetic shoe sintering
3
2, the present invention has increased silicate fiber in additive, therefore under low cost, can improve the mechanical strength of magnetic shoe greatly, and the tensile strength of magnetic shoe is reached more than the 30MPa.
3, the present invention adopts pre-sintering process, finishes solid phase reaction and generates permanent-magnet ferrite, and this permanent-magnet ferrite can reach the submicron order crystallite dimension, has best magnetic property.The present invention has increased calcium carbonate in pre-sintering process, can reduce sintering temperature, and the grain size and the pattern of control permanent-magnet ferrite can not only be beneficial to the orientation in crystal grain magnetic field, and the shrinkage can reduce double sintering the time.The present invention adopts secondary ball milling technology, and in fine grinding technology, dispersant and grinding aid have been added in the ball milling slip, by dispersant the molding mass powder is played the effect of deagglomeration,, make the crystal grain of slip be equal to or less than single-domain particle critical dimension because the slip particle size distribution is narrower, can not only obtain the fine powder material of even and high conformity, and improved the ratio of single-domain particle, refinement crystal grain, thereby increased coercivity H.Free Sr (OH) during the present invention simultaneously comes by grinding aid and in the slip
2, reduce the pH value in the slip effectively, the degree of orientation of magnetic shoe can be reached more than 98%, magnetic shoe has high HCJ again when having high residual magnetic flux density.
Embodiment
Each component of the major ingredient of permanent ferrite magnetic tile of the present invention and additive and percentage by weight thereof are detailed to be shown in Table 1.
Table 1
Title | 1# | 2# | 3# | 4# | 5# | 6# | |
Major ingredient | Strontium oxide strontia | 8.7 | 8.9 | 8.8 | 9 | 9 | 9 |
Iron oxide red | 86 | 86.5 | 86.8 | 87 | 87 | 87 | |
Additive | Calcium carbonate (pre-burning) | 0.3 | 0.2 | 0.4 | 0.5 | 0.3 | 0.5 |
Calcium carbonate | 0.3 | 0.7 | 0.4 | 0.5 | 0.4 | 0.5 | |
Alundum (Al | 0.8 | 0.9 | 0.9 | 0.6 | 0.8 | 1 | |
Chrome green | 0.4 | 0.7 | 0.8 | 1 | 0.6 | 0.5 | |
Boric acid | 0.3 | 0.5 | 0.6 | 0.5 | 0.4 | 0.4 | |
Silicon dioxide | 0.5 | 0.5 | 0.4 | 0.4 | 0.4 | 0.3 | |
Cobaltosic oxide | 0.4 | 0.4 | 0.3 | 0.2 | 0.4 | 0.4 | |
Lanthanum sesquioxide | 0.4 | 0.4 | 0.4 | 0.2 | 0.4 | 0.3 | |
Silicate fiber | 0.3 | 0.3 | 0.2 | 0.1 | 0.3 | 0.1 |
The purity of above-mentioned strontium oxide strontia 〉=98.5%, the purity of iron oxide red 〉=97.5%, the purity of additive 〉=99.5%, silicate fiber can adopt alumina silicate fibre, manganous silicate fiber, potassium silicate fiber etc.
Be the embodiment that the present invention makes permanent ferrite magnetic tile below.
Embodiment 1
(1), batching: the 1# that presses in the table 1 mixes composition pre-burning material with strontium oxide strontia, iron oxide red and calcium carbonate;
(2), pre-burning pellet mill: pre-imitation frosted glass is put into the ball mill ball milling, make the full and uniform mixing of pre-imitation frosted glass, the particle≤2 μ m of pre-imitation frosted glass;
(3), clamp dog, pre-burning: the pre-imitation frosted glass that will mix adds water and stirs, and makes pre-burning strip toughness, and the briquet type is put under the temperature of inherent 1260 ℃ ± 10 ℃ of stove and fired, and the time is controlled at 5h, fltting speed 38min/ plate~40min/ plate;
(4), pulverize: the piece material of sinter molding is put into pulverizer pulverize, the particle of powder during discharging≤3.5 μ m;
(5), batch mixing: press the 1# in the table 1, in compound, add desilicate fiber other additive in addition and mix;
(6), secondary ball milling: earlier batch mixing is carried out thick ball milling in ball mill, steel ball adopts the steel ball of three kinds of sizes, the big steel ball of Φ 10mm, the middle steel ball of Φ 8mm, and the small ball of Φ 6mm~Φ 6.3mm, mark ratio by weight, steel ball big: in: little ratio is 2: 3: 5, and expect: ball: water is 1: 5: 1.2 than then, and the corase grind time is controlled at 4h, the slip granularity is controlled at 1.0 μ m~1.3 μ m, slip is squeezed into again and carried out fine grinding in the fine grinding ball mill, the small ball of Φ 6mm~Φ 6.3mm is adopted in fine grinding, wherein, material: ball: water is 1: 8: 1.2, the ball milling time is controlled at 5h, and carry out ball milling after adding silicate fiber and dispersant and grinding aid this moment, by weight, material: dispersant: grinding aid is 1: 0.003: 0.001, the pH value of slip is controlled at 7, and the slip granularity is controlled at 0.75 μ m~0.85 μ m, and this grinding aid can be selected diluted acid or ferric sulfate for use, and dispersant is carboxylic acid or carboxylic acids salt, as selects stearic acid for use, calcium stearate, olein or olein acid calcium etc.;
(7), slip precipitation: slip is controlled at 35%~40% through the dehydration post precipitation with the slip moisture content, to improve the stability of consistency of product and production;
(8), the compacting green compact: slip is injected mould, under the pressure of 15MPa, makes green compact, magnetize with 5 Wan An circle D.C. magnetic fields, the pulsed magnetic field of the 9 Wan An circles that superpose simultaneously, the degree of orientation 〉=98%, green density is at 3.3g/cm
3~3.4g/cm
3
(9), sintering: green compact are put into inherent 1150 ℃ ± 10 ℃ sintering temperatures of stove, and the time is controlled at 2h, and fltting speed 18min/ plate is incubated 1h, adopts anxious quenching during cooling before 800 ℃, comes out of the stove;
(10), mill processing: be ground to required physical dimension, make magnetic shoe finished product of the present invention.
Embodiment 2
(1), batching: the 2# that presses in the table 1 mixes composition pre-burning material with strontium oxide strontia, iron oxide red and calcium carbonate;
(2), pre-burning pellet mill: above-mentioned pre-imitation frosted glass is put into the ball mill ball milling, make the full and uniform mixing of pre-imitation frosted glass, and the particle≤2 μ m of pre-imitation frosted glass;
(3), clamp dog, pre-burning: the pre-imitation frosted glass that will mix adds water and stirs, and makes pre-burning strip toughness, and the briquet type, puts under the temperature of inherent 1270 ℃ ± 10 ℃ of stove and fires, and the time is controlled at 4h, fltting speed 40~45min/ plate;
(4), pulverize: the piece material of sinter molding is put into pulverizer pulverize, the particle of powder during discharging≤3.5 μ m;
(5), batch mixing: press the 2# in 1, in compound, add desilicate fiber other additive in addition and mix;
(6), secondary ball milling: earlier batch mixing is carried out thick ball milling in ball mill, steel ball adopts the steel ball of three kinds of sizes, the big steel ball of Φ 10mm, the middle steel ball of Φ 8mm, and the small ball of Φ 6mm~Φ 6.3mm, wherein: mark ratio by weight, steel ball big: in: little ratio is 2: 3: 5, expect: ball: water is 1: 6: 1.2 than then, the corase grind time is controlled at 4.5h, the slip granularity is controlled at 1.0 μ m~1.3 μ m, again slip is squeezed into and carried out fine grinding in the fine grinding ball mill, the small ball of Φ 6mm~Φ 6.3mm is adopted in fine grinding, material: ball: the water ratio is 1: 10: 1.5, the ball milling time is controlled at 4.8h, carry out ball milling after adding silicate fiber and dispersant and grinding aid this moment, by ratio of weight and the number of copies, powder: dispersant: grinding aid is 1: 0.004: 0.002, the pH value of slip is controlled at 8.5, the slip grain is controlled at 0.75 μ m~0.85 μ m, this grinding aid can be selected ammonium carbonate or carbonic hydroammonium for use, and dispersant is carboxylic acid and carboxylic acids salt, as selects aluminum stearate for use, zinc stearate, olein acid barium or olein acid strontium etc.;
(7), slip precipitation: slip is controlled at 40%~45% through the dehydration post precipitation with the slip moisture content, to improve the stability of consistency of product and production;
(8), the compacting green compact: slip is injected mould, under the pressure of 16MPa, makes green compact, magnetize with 6 Wan An circle D.C. magnetic fields, the pulsed magnetic field of the 10 Wan An circles that superpose simultaneously, the degree of orientation 〉=98%, green density is at 3.3g/cm
3~3.4g/cm
3
(9), sintering: green compact are put into the stove sintering temperature at 1160 ℃ ± 10 ℃, and the time is controlled at 2.5h, and fltting speed 13min/ plate is incubated 1.5h, adopts anxious quenching during cooling before 800 ℃; Come out of the stove;
(10), mill processing: be ground to required physical dimension, make magnetic shoe finished product of the present invention.
Embodiment 3
(1), batching: the 3# that presses in the table 1 mixes composition pre-burning material with strontium oxide strontia, iron oxide red and calcium carbonate;
(2), pre-burning pellet mill: pre-imitation frosted glass is put into the ball mill ball milling, make the full and uniform mixing of pre-imitation frosted glass, and the particle≤2 μ m of pre-imitation frosted glass;
(3), clamp dog, pre-burning: the pre-imitation frosted glass that will mix adds water and stirs, and makes pre-burning strip toughness, and the briquet type, puts under the temperature of inherent 1270 ℃ ± 5 ℃ of stove and fires, and the time is controlled at 4h, fltting speed 42~45min/ plate;
(4), pulverize: the piece material of sinter molding is put into pulverizer pulverize, the particle of powder during discharging≤3.5 μ m;
(5), batch mixing: press the 3# in the table 1, in compound, add desilicate fiber other additive in addition and mix;
(6), secondary ball milling: earlier batch mixing is carried out thick ball milling in ball mill, steel ball adopts the steel ball of three kinds of sizes, the big steel ball of Φ 10mm, the middle steel ball of Φ 8mm, and the small ball of Φ 6mm~Φ 6.3mm, mark ratio by weight, steel ball big: in: little ratio is 2: 3: 5, expect: ball: water is 1: 6: 1.8 than then, and the corase grind time is controlled at 5h, and the slip granularity is controlled at 1.0~1.3 μ m, again slip is squeezed into and carried out fine grinding in the fine grinding ball mill, the small ball of Φ 6mm~Φ 6.3mm is adopted in fine grinding, and its material: ball: the water ratio is 1: 10: 1.2, and the ball milling time is controlled at 4.3h, carry out ball milling after adding silicate fiber and dispersant and grinding aid this moment, by ratio of weight and the number of copies, powder: dispersant: the grinding aid ratio is 1: 0.003: 0.003, and the pH value of slip is controlled at 7.5, the slip granularity is controlled at 0.75~0.85 μ m, this grinding aid can be selected ammonium carbonate or carbonic hydroammonium for use, and dispersant is carboxylic acid and carboxylic acids salt, as selects dolomol for use, the stearic strontium of calcium or; Olein acid magnesium, olein acid aluminium;
(7), slip precipitation: slip is controlled at 38%~42% through the dehydration post precipitation with the slip moisture content, to improve the stability of consistency of product and production;
(8), the compacting green compact: slip is injected mould, under the pressure of 18MPa, makes green compact, magnetize with 7 Wan An circle D.C. magnetic fields, the pulsed magnetic field of the 9.5 Wan An circles that superpose simultaneously, the degree of orientation 〉=98%, green density is at 3.2g/cm
3~3.3g/cm
3
(9), sintering: green compact are put into inherent 1140 ℃ ± 10 ℃ sintering temperatures of stove, and the time is controlled at 1.8h, and fltting speed 12min/ plate is incubated 2h, adopts anxious quenching during cooling before 800 ℃, comes out of the stove;
(10), mill processing: be ground to required physical dimension, make magnetic shoe finished product of the present invention.
Embodiment 4
(1), batching: the 4# that presses in the table 1 mixes composition pre-burning material with strontium oxide strontia, iron oxide red and calcium carbonate;
(2), pre-burning pellet mill: pre-imitation frosted glass is put into the ball mill ball milling, make the full and uniform mixing of pre-imitation frosted glass, and the particle≤2 μ m of pre-imitation frosted glass;
(3), clamp dog, pre-burning: the pre-imitation frosted glass that will mix adds water and stirs, and makes pre-burning strip toughness, and the briquet type, puts under the temperature of inherent 1260 ℃ ± 10 ℃ of stove and fires, and the time is controlled at 5h, fltting speed 40~43min/ plate;
(4), pulverize: the piece material of sinter molding is put into pulverizer pulverize, the particle of powder during discharging≤3.5 μ m;
(5), batch mixing: press the 4# in the table 1, in compound, add desilicate fiber other additive in addition and mix;
(6), secondary ball milling: earlier batch mixing is carried out thick ball milling in ball mill, steel ball adopts the steel ball of three kinds of sizes, the big steel ball of Φ 10mm, the middle steel ball of Φ 8mm, and the small ball of Φ 6mm~Φ 6.3mm, mark ratio by weight, steel ball big: in: little is 2: 3: 5, expect: ball: water is 1: 7: 1.6 than then, and the corase grind time is controlled at 4.2h, and the slip granularity is controlled at 1.0 μ m~1.3 μ m, again slip is squeezed into and carried out fine grinding in the fine grinding ball mill, the small ball of Φ 6mm~Φ 6.3mm is adopted in fine grinding, and material: ball: the water ratio is 1: 12: 1.8, and the ball milling time is controlled at 4.6h, carry out ball milling after adding silicate fiber and dispersant and grinding aid this moment, by ratio of weight and the number of copies, powder: dispersant: the grinding aid ratio is 1: 0.004: 0.002, and the pH value of slip is controlled at 8, the slip granularity is controlled at 0.75 μ m~0.85 μ m, this grinding aid can be selected ammonium carbonate or carbonic hydroammonium for use, and dispersant is carboxylic acid and carboxylic acids salt, as selects sour calcium barium stearate or olein acid zinc etc. for use;
(7), slip precipitation: slip is controlled at 39%~44% through the dehydration post precipitation with the slip moisture content, to improve the stability of consistency of product and production;
(8), the compacting green compact: slip is injected mould, under the pressure of 17MPa, makes green compact, magnetize with 7 Wan An circle D.C. magnetic fields, the pulsed magnetic field of the 10 Wan An circles that superpose simultaneously, the degree of orientation 〉=98%, green density is at 3.2g/cm
3~3.3g/cm
3
(9), sintering: green compact are put into inherent 1170 ℃ ± 10 ℃ sintering temperatures of stove, and the time is controlled at 2.2h, and fltting speed 15min/ plate is incubated 1.5h, adopts anxious quenching during cooling before 800 ℃, comes out of the stove;
(10), mill processing: be ground to required physical dimension, make magnetic shoe finished product of the present invention.
Embodiment 5
(1), batching: the 5# that presses in the table 1 mixes composition pre-burning material with strontium oxide strontia, iron oxide red and calcium carbonate;
(2), pre-burning pellet mill: pre-imitation frosted glass is put into the ball mill ball milling, make the full and uniform mixing of pre-imitation frosted glass, the particle≤2 μ m of pre-imitation frosted glass;
(3), clamp dog, pre-burning: the pre-imitation frosted glass that will mix adds water and stirs, and makes pre-burning strip toughness, and the briquet type, puts under the temperature of inherent 1270 ℃ ± 5 ℃ of stove and fires, and the time is controlled at 5.5h, fltting speed 42min/ plate~45min/ plate;
(4), pulverize: the piece material of sinter molding is put into pulverizer pulverize, the particle of powder during discharging≤3.5 μ m;
(5), batch mixing: press the 5# in the table 1, other additive in compound beyond the adding desilicate fiber also mixes;
(6), secondary ball milling: earlier batch mixing is carried out thick ball milling in ball mill, steel ball adopts the steel ball of three kinds of sizes, the big steel ball of Φ 10mm, the middle steel ball of Φ 8mm, and the small ball of Φ 6mm~Φ 6.3mm, mark ratio by weight, steel ball big: in: little is 2: 3: 5, expect: ball: water is 1: 7: 1.5 than then, the corase grind time is controlled at 4.8h, and the slip granularity is controlled at 1.0 μ m~1.3 μ m, slip is squeezed into carried out fine grinding in the fine grinding ball mill again, the small ball of Φ 6mm~Φ 6.3mm is adopted in fine grinding, material: ball: the water ratio is 1: 12: 1.3, and the ball milling time is controlled at 4.8h, and carry out ball milling after adding silicate fiber and dispersant and grinding aid this moment, by ratio of weight and the number of copies, powder: dispersant: the grinding aid ratio is 1: 0.003: 0.003, and the pH value of slip is controlled at 9, and the slip granularity is controlled at 0.75 μ m~0.85 μ m, this grinding aid can be selected ammonium carbonate or carbonic hydroammonium for use, and dispersant is phosphoric acid fat and its esters;
(7), slip precipitation: slip is controlled at 40%~45% through the dehydration post precipitation with the slip moisture content, to improve the stability of consistency of product and production;
(8), the compacting green compact: slip is injected mould, under the pressure of 17MPa, makes green compact, magnetize with 7 Wan An circle D.C. magnetic fields, the pulsed magnetic field of the 10 Wan An circles that superpose simultaneously, the degree of orientation 〉=98%, green density is at 3.2g/cm
3~3.3g/cm
3
(9), sintering: green compact are put into inherent 1180 ℃ ± 10 ℃ sintering temperatures of stove, and the time is controlled at 1.5h, and fltting speed 17min/ plate is incubated 1.2h, adopts anxious quenching during cooling before 800 ℃, comes out of the stove;
(10), mill processing: be ground to required physical dimension, make magnetic shoe finished product of the present invention.
Embodiment 6
(1), batching: the 6# that presses in the table 1 mixes composition pre-burning material with strontium oxide strontia, iron oxide red and calcium carbonate;
(2), pre-burning pellet mill: pre-imitation frosted glass is put into the ball mill ball milling, make the full and uniform mixing of pre-imitation frosted glass, and the particle≤2 μ m of pre-imitation frosted glass;
(3), clamp dog, pre-burning: the pre-imitation frosted glass that will mix adds water and stirs, and makes pre-burning strip toughness, and the briquet type, puts under the temperature of inherent 1260 ℃ ± 5 ℃ of stove and fires, and the time is controlled at 5h, fltting speed 38~40min/ plate;
(4), pulverize: the piece material of sinter molding is put into pulverizer pulverize, the particle of powder during discharging≤3.5 μ m;
(5), batch mixing: press the 6# in the table 1, in compound, add desilicate fiber other additive in addition and mix;
(6), secondary ball milling: earlier batch mixing is carried out thick ball milling in ball mill, steel ball adopts the steel ball of three kinds of sizes, the big steel ball of Φ 10mm, the middle steel ball of Φ 8mm, and the small ball of Φ 6mm~Φ 6.3mm, mark ratio by weight, steel ball big: in: little ratio is 2: 3: 5, expect: ball: water is 1: 5: 1.4 than then, the corase grind time is controlled at 5h, and the slip granularity is controlled at 1.0 μ m~1.3 μ m, slip is squeezed into carried out fine grinding in the fine grinding ball mill again, the small ball of Φ 6mm~Φ 6.3mm is adopted in fine grinding, material: ball: the water ratio is 1: 9: 1.8, and the ball milling time is controlled at 5h, and carry out ball milling after adding silicate fiber and dispersant and grinding aid this moment, by ratio of weight and the number of copies, powder: dispersant: the grinding aid ratio is 1: 0.003: 0.002, and the pH value of slip is controlled at 8.5, and the slip granularity is controlled at 0.75 μ m~0.85 μ m, this grinding aid can be selected diluted acid or ferric sulfate for use, and dispersant is sulfuric acid ester and its esters;
(7), slip precipitation: slip is controlled at 35%~40% through the dehydration post precipitation with the slip moisture content, to improve the stability of consistency of product and production;
(8), the compacting green compact: slip is injected mould, under the pressure of 15MPa, makes green compact, magnetize with 5 Wan An circle D.C. magnetic fields, the pulsed magnetic field of the 9 Wan An circles that superpose simultaneously, the degree of orientation 〉=98%, green density is at 3.3g/cm
3~3.4g/cm
3
(9), sintering: green compact are put into inherent 1190 ℃ ± 10 ℃ sintering temperatures of stove, and the time is controlled at 2h, and fltting speed 16min/ plate is incubated 1h, adopts anxious quenching during cooling before 800 ℃, comes out of the stove;
(10), mill processing: be ground to required physical dimension, make magnetic shoe finished product of the present invention.
Magnetic shoe finished product of the present invention is detected, and it detects data and sees Table 2
Table 2:
Test item | 1# | 2# | 3# | 4# | 5# | 6# |
Br(mT) | 430 | 428 | 432 | 420 | 435 | 440 |
Hcb(kA/m) | 318 | 319 | 316 | 320 | 316 | 313 |
Hcj(kA/m ) | 398 | 397 | 396 | 400 | 396 | 395 |
(BH)max(kJ/m 3) | 32 | 32.2 | 31.8 | 32.8 | 32 | 32.6 |
H k(kA/m) | 398 | 396 | 397 | 399 | 395 | 393 |
Tensile strength (MPa) | 30.0 | 30.5 | 30.8 | 31 | 30.8 | 30.5 |
As can be seen from Table 2, adopt major ingredient of the present invention and properly mixed additive, and be equipped with product that special manufacture craft makes when having high residual magnetic flux density, have high HCJ again, and can also reach high performance requirement.
Claims (6)
1. a permanent ferrite magnetic tile comprises major ingredient and additive, it is characterized in that: described major ingredient and components of additives and percentage by weight thereof are as follows,
Major ingredient: strontium oxide strontia 8.7%~9.0%
Iron oxide red 86%~87%
Additive: calcium carbonate 0.6%~1.0%
Alundum (Al 0.6%~1.0%
Chrome green 0.4%~0.8%
Boric acid 0.3%~0.6%
Silicon dioxide 0.3%~0.5%
Cobaltosic oxide 0.2%~0.4%
Lanthanum sesquioxide 0.2%~0.4%
Silicate fiber 0.1%~0.3%.
2. the manufacture method of a permanent ferrite magnetic tile is characterized in that:
(1), batching: by weight percentage with 8.7%~9.0% strontium oxide strontia, 86%~87% iron oxide red and 0.2%~0.5% calcium carbonate mix forms the pre-burning material;
(2), pre-burning pellet mill: pre-imitation frosted glass is put into the ball mill ball milling, pre-imitation frosted glass is evenly mixed, the particle≤2 μ m of pre-imitation frosted glass;
(3), clamp dog, pre-burning: pre-imitation frosted glass is added water stir back briquet type, put into stove and fire under 1250 ℃-1280 ℃ temperature, the time is controlled at 4h~6h, fltting speed 38~45min/ plate;
(4), pulverize: the piece material of sinter molding is pulverized the particle of powder≤3.5 μ m;
(5), batch mixing: in compound, add 0.3%~0.5% calcium carbonate, 0.6%~1.0% alundum (Al, 0.4%~0.8% chrome green, 0.3%~0.6% boric acid, 0.3%~0.5% silicon dioxide, 0.2%~0.4% cobaltosic oxide and 0.2%~0.4% lanthanum sesquioxide by weight percentage, and mix;
(6), secondary ball milling: earlier batch mixing is carried out thick ball milling in ball mill, the slip granularity is controlled at 1.0 μ m~1.3 μ m, slip is squeezed in the fine grinding ball mill again, and add 0.1%~0.3% silicate fiber and dispersant and grinding aid and carry out ball milling, by ratio of weight and the number of copies, powder: dispersant: the grinding aid ratio is 1: 0.003~0.005: 0.001~0.003, and the pH value of slip is controlled between 7~9, and the slip granularity is controlled at 0.75 μ m~0.85 μ m;
(7), slip precipitation: the slip precipitation is dewatered, and the slip moisture content is controlled at 35%~45%;
(8), the compacting green compact: slip is injected mould, under the pressure of 15MP~18MPa, makes green compact, magnetize with 5~7 Wan An circle D.C. magnetic fields, the pulsed magnetic field of 9~10 Wan An circles that superpose simultaneously, the degree of orientation 〉=98%, green density is at 3.2g/cm
3~3.4g/cm
3
(9), sintering: green compact are put into the inherent 1130-1200 ℃ of sintering temperature of stove, and the time is controlled at 1.5h~2.5h, and fltting speed 12~18min/ plate is incubated 1h~2h, adopts anxious quenching during cooling before 800 ℃, comes out of the stove;
(10), mill processing: be ground to required physical dimension, make finished product.
3. the manufacture method of permanent ferrite magnetic tile according to claim 2, it is characterized in that: described when thick ball milling, adopt big steel ball and the middle steel ball of Φ 8mm and the small ball of Φ 6mm~Φ 6.3mm of Φ 10mm, mark ratio by weight, steel ball big: in: little ratio is 2: 3: 5, material: ball: the water ratio is 1: 5~7: 1.2~1.8, and the corase grind time is controlled at 4h~5h.
4. the manufacture method of permanent ferrite magnetic tile according to claim 2, it is characterized in that: during described thin ball milling, adopt the small ball of Φ 6mm~Φ 6.3mm, by weight the mark ratio, material: ball: the water ratio is 1: 8~12: 1.2~1.8, and the ball milling time is controlled at 4h~5h.
5. the manufacture method of permanent ferrite magnetic tile according to claim 2, it is characterized in that: described grinding aid is selected the wherein a kind of of diluted acid, ferric sulfate, ammonium carbonate or carbonic hydroammonium for use.
6. the manufacture method of permanent ferrite magnetic tile according to claim 2, it is characterized in that: described dispersant is carboxylic acid or carboxylic acids salt, or phosphoric acid fat and its esters, or sulfuric acid ester and its esters.
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