JPS60152656A - Magnetic material having high performance and its manufacture - Google Patents

Abstract

PURPOSE:To manufacture a magnetic material having high performance by adding a specified amount of one or more among B2O3, GeO and SnO2 to an Fe base alloy contg. specified percentages of Al and Si. CONSTITUTION:An Fe base alloy consisting of 3-13wt% Al, 3-13wt% Si and the balance Fe is ground to powder of 1-10mum particle size, and this powder is mixed with 0.001-7wt% fine powder of one or more among B2O3, GeO and SnO2. The mixture is compression-molded and sintered at 360-1,000 deg.C to obtain a magnetic material having high performance. The magnetic material has high saturation magnetic flux density, a small loss in a high frequency range and high magnetic permeability.

Description

[Detailed description of the invention]

The present invention relates to a method for producing a high-performance magnetic material having high saturation magnetic flux density, low loss in a high frequency range, and high magnetic permeability. In recent years, there has been a demand for higher density recording in digital magnetic recording, audio, VTR, etc., and the gap length and track width have been narrowed to make efficient use of the recording medium surface. However, when the gap length and track width are narrowed, the reproduction output decreases. This causes errors in digital magnetic recording, and causes a reduction in the signal-to-noise ratio in audio, VTR, and the like. Therefore, it is a common idea to prevent a decrease in reproduction output by increasing the coercive force of the recording medium, and such high coercive force media have been developed. Therefore, as the coercive force of the recording medium increases, the material used for the magnetic head that performs input/output on the recording medium also needs to have an increased saturation magnetic flux density. Ferrite and sendust, which are conventional magnetic head materials, are insufficient materials for high-density recording magnetic heads. F]nirite has less loss in the high frequency range and has high reproduction efficiency +A FI, but the saturation magnetic flux density is 5.
500 Ga1lSS ('iIQ), so it is difficult to record well on a coercive medium. On the other hand, Lengst, which is an Fe-A I-3i alloy, has a saturation magnetic flux density of 9,000 Gauss and is very difficult to record well on coercive media. ~
However, it has the drawbacks of high eddy current loss in the high frequency range and low reproduction efficiency. The present invention aims to form a resistance layer at grain boundaries in Fe-^1-3i alloys, increase electrical resistance, prevent the generation of eddy currents, and improve regeneration efficiency. [1] The present invention is explained below.
%, Si: 3 to 13 wt%, balance: [In the base alloy consisting of e, B 203. GeQ, sno2
It is a magnetic material in which 0.001-7 w1% of at least one of these is added, and is a sintered alloy obtained by mixing base alloy powder and additive alloy fine powder and sintering and solidifying the mixture. The reason for limiting the addition value is that if the amount is 0.001 wt%, the generation of eddy current cannot be prevented, and if it exceeds 7 wt%, the saturation magnetic flux density will decrease significantly. Furthermore, the present invention provides a method for producing the same,
The above alloy was made into a powder of 1 to 10%, and B203, Ge
m, fine powder of at least one kind of SnO2<
After adding 1.001 to 7111 t% and mixing, compression molding
It is sintered at a temperature of 60 to 1,100°C, and as a result, B203. A resistive layer of at least one of Gem and 5 nOz is formed, and the closed porosity can be made 0.5% or less. If the temperature is lower than 360°C, it will not be sintered, and if the temperature exceeds 1,100°C, it will react with the outside. Next, 300~1,000℃, 500~2,
000/(!? / By performing hot isostatic compression with crA, the resistance layer existing at the grain boundaries) is made extremely thin, and the closed porosity becomes close to 0%, preventing a decrease in the saturation magnetic flux density. 300℃ and 5008FI/c
If it is less than #1, it will not be densified, and if it is less than 1,000℃ and 2
,00ON9/crA, it will react with the outside. An example of the manufacturing method of the present invention will be shown below.

【Example】

AI 5.4wt%, Si 9.6wt%, Fe8
After weighing to 5 wt % and uniformly melting it in a vacuum or inert atmosphere using a high frequency melting furnace, it is deoxidized and desulfurized to remove impurities to create a molten alloy with a uniform composition. Next, this alloy is directly pulverized by an ultrasonic method or an injection method, or it is made into an ingot and then mechanically pulverized to obtain a fine powder. To this fine powder, 0.001 to 7 wt % of at least one type of fine powder among B203, GeQ, and SnO2 is added, mixed, compression molded, and sintered at a temperature of 360 to 1,100°C. At this time, by setting the closed porosity to 0.5% or less, the effect of the next hot isostatic compression can be fully exhibited. and 300-1,000℃, 500℃
Hot isostatic pressing at ~2,00 ONg/c111. When the Fe-Al-Si alloy obtained as described above is used as a magnetic head, it becomes a high-performance magnetic material exhibiting the following physical properties. (i) Since it is a Fe-A I-3i alloy, it has a high saturation magnetic flux density (8,000 to 10,000 Gauss
). (i) Due to hot isostatic compression, the grain boundary layer becomes extremely 5
− It has high magnetic permeability because it is thin and dense. (b) Since the grain boundary layer is an electrical insulator, the electrical resistivity is large. (to) “(!-^1-8i alloy B203, GeQ
, because oxides such as SnO2 are used at grain boundaries,
The abrasion resistance 4:1 is high at 1°. Therefore, the present invention has a wide range of applications, including not only magnetic heads but also iron core materials for converters such as digital magnetic recording, audio, and VTR. Patent applicant Namiki Precision Jewel Co., Ltd. 6-

Claims (1)

[Claims] fllAl: 3 to 13 wt%, Si: 3 to 1
In the base alloy consisting of 3 wt%, balance: Fe, 820
3. GeQ. At least one type of SnO2 - is o, ooi~
A high-performance magnetic material characterized by the addition of 7wt%. (2) Eight I: 3-13wt%, St: 3-13w
t%, remainder: [eJ: In the base alloy, the alloy is powdered in 1 to 10 parts, and at least one fine powder of B2O3, ΩeQ, and 5nQ2 is added to o, ooi to 7w.
A method for producing a high-performance magnetic material, which comprises adding and mixing t%, compression molding, and sintering and covering at 360 to 1,100°C. (3) After sintering, further 300~i, ooo℃,
500~2,0OOK! ? A method for producing a high-performance magnetic material according to claim (2), wherein hot isostatic compression is carried out at /ctA.