CN1035088C - High-magnetic heat stability cobalt improved r-ferric oxide magnet powder and its made method - Google Patents
High-magnetic heat stability cobalt improved r-ferric oxide magnet powder and its made method Download PDFInfo
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- CN1035088C CN1035088C CN92105419A CN92105419A CN1035088C CN 1035088 C CN1035088 C CN 1035088C CN 92105419 A CN92105419 A CN 92105419A CN 92105419 A CN92105419 A CN 92105419A CN 1035088 C CN1035088 C CN 1035088C
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- magnetic
- heat stability
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- cobalt improved
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Abstract
The present invention relates to a method for making mixing cobalt improved r-Fe#-[2]O#-[3] magnetic powder, particularly to the cobalt improved r-Fe#-[2]O#-[3] magnetic powder mixed with Mn or P with high-magnetic thermal stability and the making method thereof. In the present invention, the surface of the cobalt improved r-Fe#-[2]O#-[3] is covered with the Mn or the P and the ions are diffused into the crystal lattices of the magnetic powder by means of heat treatment. When a magnetic field and temperature simultaneously acts, the activation energy of Co iron migration is greatly improved so that the magnetic thermal stability of the coercive force of the magnetic powder is improved. The Y&CO#-[x]R#-[y]Fe#-[3-x-y]O#-[4] (R=Mn or P) magnetic powder made by the method is suitable for manufacturing video tapes, digital recording tapes, magnetic disks, etc.
Description
The present invention relates to a kind of preparation cobalt improved γ-Fe that mixes
2O
3The method of magnetic, particularly preparation are mixed the cobalt improved γ-Fe of the high-magnetic heat stability of phosphorus
2O
3The magnetic method.
Wrap the γ-Fe of attached Conjugate ferrite
2O
3Magnetic is the magnetic that is widely used in video recording and aspects such as digital record tape and disk at present.But there is the imperfect shortcoming of coercitive magnetic heat stability in it: the tape made from it has the signal of former record to be difficult for wiping under magnetic field and temperature act on simultaneously, shortcoming such as print-through is big.People such as Eiling mention in magnetic collects publication [A.Eilingand R.A.Rott, IEEE T.Magn.MAG-21 (5) (1985) 1497] article, have invented a kind of cobalt improved γ-Fe of high-magnetic heat stability
2O
3Magnetic, after 100 hours, its coercive force only drops to about 1% of original value, but does not provide the preparation technology of this magnetic at 40 ℃ and 3000 Oe the action of a magnetic fields for it.People such as Marcott narrate in the U.S.'s 4209412 patents, when preparation FeOOH, add CoSO simultaneously
4Solution and phosphatase reaction after reduction and oxidation, are made and are contained Co, γ-Fe of P
2O
3Magnetic.The coercive force of magnetic is improved.But whether they do not refer to the concrete preparation method and the coercitive magnetic heat stability of magnetic of this magnetic good.
The objective of the invention is to overcome the shortcoming and defect of above-mentioned prior art, in order to improve cobalt improved γ-Fe
2O
3The magnetic heat stability of magnetic, thus provide a kind of at cobalt improved γ-Fe
2O
3The magnetic surface makes the P ions diffusion with the attached P ion of chemical coprecipitation method bag in crystal through Overheating Treatment, forms Co
xP
yFe
3-x-yO
4Have high-magnetic heat stability magnetic and preparation method thereof
The object of the present invention is achieved like this:
With γ-Fe
2O
3Magnetic places in the reactor, adds the distilled water of 10 times of magnetic weight, is warming up to 90-100 ℃, and the blender about 100 rev/mins with rotating speed is sequentially added into FeSO while stirring
47H
2O, CoSO
47H
2O and (NaPO
3) 6 solution, after stirring in 10-60 minute, adding concentration while stirring is the NaoH solution of 200g/l.Afterwards, continue after stirring 50-150 minute between 90-100 ℃, sediment to be filtered, be washed till (neutrality) between the PH=6-8,, put into tube furnace then, at N 60-80 ℃ of oven dry down with distilled water
2Under the inert atmosphere, be heated to 390 ℃ of heat treatments 2 hours, be cooled to again between 200-250 ℃, oxidation 5-15 minute.After buried at above-mentioned heat place, cobalt and phosphorous diffusion were to γ-Fe
2O
3In the magnetic body, make and mix the cobalt improved ferrite Co of phosphorus
xP
yFe
3-x-yO
4The migration activation energy of the cobalt ions of magnetic is not more mixed the height of the magnetic of P, thereby the coercitive magnetic heat stability of magnetic is improved.The main chemical reactions formula of said process is as follows;
High-magnetic heat stability cobalt improved γ-Fe of the present invention
2O
3The composition formula of magnetic is as follows:
Co
x P
y Fe
3-x-yO
4；
Wherein: x=y=0.01-0.2
Add each composition by γ-Fe
2O
3Percentage by weight is: the ((NaPO of 0-40Wt%
3); The CoSO of 5-40Wt%
4.7H
2O, the FeSO of 50-100Wt%
4.7H
2O.
Be elaborated below in conjunction with embodiment:
Embodiment 1
At room temperature with 10 gram needle-like γ-Fe
2O
3(long 0.5 μ m, mean axis be than 10: 1, coercivity H: 400 Oe) put into the reaction vessel of 0.5 liter, 200 milliliters of adding distil waters are warming up to 95 ℃ to magnetic, dispersed with stirring 1 hour.Under constantly stirring,, add the CoSO that concentration is 95 grams per liters successively every 10 minutes
47H
220 milliliters of O solution; 5 milliliters of the NaOH solution of 200 grams per liters, the FeSO of 125 grams per liters
47H
235 milliliters of the NaOH solution of 40 milliliters of O solution and 200 grams per liters.(the NaPO that when PH=8, adds 20 grams per liters
3)
620 milliliters of solution; After above-mentioned material adds, continue to stir 1 hour, be washed to PH=7; Filter, in oven dry below 60 ℃.
The magnetic that above-mentioned cladding is good is put into tube furnace, at N
2Under the atmosphere, 390 ℃ of heat treatment 2 hours, again 210 ℃ of oxidations about 10 minutes, this moment magnetic ferrous content at 1-3%.
The chemical composition analysis result of the magnetic that makes like this is: Co
2+=3.49wt%, Fe
2+=2.1wt%; P=0.88wt%
The basic magnetic of magnetic:
Coercive force HC=721 Oe specific saturation magnetization σ
s=71.6emu/g
Magnetic is dispersed in the binder solution, is coated on the dacron chip base, in 2000 Oe are parallel to the magnetic field of sheet base, put driedly, make magnetic sheet.At this moment, the coercive force HC that is parallel to direction of orientation
∥=803 Oe.
Smear sample is placed in the magnetic field of 3000 Oe, handled 12 hours at 90 ℃ perpendicular to sheet base direction in magnetic field.The coercive force H ' of the former direction of orientation of smear sample after magnetic heat treatment
C ∥=788 Oe
Therefore, the ratio of the coercive force before and after the smear sample magnetic heat treatment: H '
∥/ HC
∥=98%; Promptly after magnetic heat treatment, the coercive force of sample has only descended 2% than before handling.
Embodiment 2
This is a reference example, is used for doing contrast with the performance of mixing the cobalt improved magnetic of P.
Press the cobalt improved γ-Fe of prepared of embodiment 1
2O
3Magnetic is except that not adding (NaPO
3)
6, outside the aqueous solution, all the other steps are all constant.The coercive force HC=729 Oe of the magnetic that makes like this; σ
sThe coercive force H of=73.2emn/g smear sample
C ∥=815 Oe.
Smear sample through with embodiment 1 the same terms magnetic heat treatment after, its coercive force H '
C ∥=717 Oe.
So do not mix cobalt improved γ-Fe of P
2O
3The ratio of the coercive force of magnetic magnetic heat treatment: H '
C ∥/ H
C ∥=88%.The coercive force that is magnetic has descended 12% after magnetic heat treatment; Than mixing the cobalt improved γ-Fe of P
2O
3The coercitive magnetic heat stability of magnetic differs from about 10%.
Claims (3)
1, the high-magnetic heat stability cobalt improved γ-Fe of a kind of preparation
2O
3The method of magnetic comprises the following steps:
With γ-Fe
2O
3Magnetic is that raw material places in the reaction vessel, adds the distilled water of 10 times of magnetic weight, is warming up to 90-100 ℃, stirs with the blender limit of 100 rev/mins of rotating speeds, and the limit adds CoSO in order
47H
2O, FeSO
47H
2O and (NaPO
3)
6Solution adds each composition by γ-Fe
2O
3Percentage by weight is: (the NaPO of 10-40wt%
3)
6, the CoSO of 5-40Wt%
47H
2The FeSo of O and 50-100wt%
47H
2O stirred through 10-60 minute, and the NaOH solution that adds 200 grams per liters is stirred on the limit, afterwards, continuation is filtered sediment after stirring 50-150 minute between 90-100 ℃, is washed till (neutrality) between the PH=6-8 with distilled water, 60-80 ℃ of oven dry down, put into tube furnace, again at N
2Under the inert atmosphere, be heated to 390 ℃, heat treatment 2 hours is cooled between 200-250 ℃ again, oxidation 5-15 minute.
2, by the high-magnetic heat stability cobalt improved γ-Fe of the described preparation of claim 1
2O
3The method of magnetic is characterized in that described inert gas is N
2
3, a kind of by the direct high-magnetic heat stability magnetic of manufacturing of the described preparation method of claim 1 institute, it is characterized in that: it consists of Cox R
yFe
3-x-yO
4
Wherein: x=y=0.01-0.2
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN92105419A CN1035088C (en) | 1992-07-10 | 1992-07-10 | High-magnetic heat stability cobalt improved r-ferric oxide magnet powder and its made method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN92105419A CN1035088C (en) | 1992-07-10 | 1992-07-10 | High-magnetic heat stability cobalt improved r-ferric oxide magnet powder and its made method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1071027A CN1071027A (en) | 1993-04-14 |
| CN1035088C true CN1035088C (en) | 1997-06-04 |
Family
ID=4941374
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN92105419A Expired - Fee Related CN1035088C (en) | 1992-07-10 | 1992-07-10 | High-magnetic heat stability cobalt improved r-ferric oxide magnet powder and its made method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN1035088C (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101824237B (en) * | 2010-05-05 | 2012-07-04 | 太原理工大学 | Method for modifying and whitening kaolin |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5135696A (en) * | 1974-09-20 | 1976-03-26 | Fuji Photo Film Co Ltd | |
| JPS5135697A (en) * | 1974-09-20 | 1976-03-26 | Fuji Photo Film Co Ltd | |
| JPS53132799A (en) * | 1977-04-22 | 1978-11-18 | Fuji Photo Film Co Ltd | Manufacture of strong magnetic powder |
| GB2080783A (en) * | 1980-07-31 | 1982-02-10 | Hercules Inc | Process for producing ferromagnetic metallic particles |
| GB2127797A (en) * | 1982-09-16 | 1984-04-18 | Ishihara Mining & Chemical Co | Process for producing magnetic powder |
| JPH01203226A (en) * | 1988-02-10 | 1989-08-16 | Ishihara Sangyo Kaisha Ltd | Production of ferromagnetic iron oxide containing cobalt |
-
1992
- 1992-07-10 CN CN92105419A patent/CN1035088C/en not_active Expired - Fee Related
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5135696A (en) * | 1974-09-20 | 1976-03-26 | Fuji Photo Film Co Ltd | |
| JPS5135697A (en) * | 1974-09-20 | 1976-03-26 | Fuji Photo Film Co Ltd | |
| JPS53132799A (en) * | 1977-04-22 | 1978-11-18 | Fuji Photo Film Co Ltd | Manufacture of strong magnetic powder |
| GB2080783A (en) * | 1980-07-31 | 1982-02-10 | Hercules Inc | Process for producing ferromagnetic metallic particles |
| GB2127797A (en) * | 1982-09-16 | 1984-04-18 | Ishihara Mining & Chemical Co | Process for producing magnetic powder |
| JPH01203226A (en) * | 1988-02-10 | 1989-08-16 | Ishihara Sangyo Kaisha Ltd | Production of ferromagnetic iron oxide containing cobalt |
Also Published As
| Publication number | Publication date |
|---|---|
| CN1071027A (en) | 1993-04-14 |
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