JPS61107703A - Composite magnetic material - Google Patents

Abstract

PURPOSE:To improve junction strength and mass productivity by joining a metal magnetic material with a metal magnetic thin film which is formed on an oxide magnetic material. CONSTITUTION:A metal magnetic thin film 3 such as Sendust is formed on an oxide magnetic material block 1 such as ferrite by evaporation, sputtering, etc. The metal magnetic thin film 3 and a metal magnetic material block 2 are joined by brazing with such as silver and a composite magnetic material block is formed. The junction can be made very strong and easily since the oxide magnetic material and the metal magnetic material are joined with the metal magnetic thin film 3 in this way.

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a composite magnetic material in which different types of magnetic materials are joined, and in particular, an oxide magnetic material such as ferrite containing polycrystals and a metal magnetic material such as sendust containing single crystals. The present invention relates to a composite magnetic material in which materials are laminated.

[Technical background of the invention]

Laminated composite magnetic materials are used in various technical fields with the development of electronic technology, and they also play a major role in the field of magnetic heads used for magnetic recording.

In recent years, high coercive force recording media such as metal tapes have been developed due to the increase in the density of magnetic recording, and along with this,
The development of magnetic materials for use in magnetic heads that are compatible with this high coercive force recording medium is also actively underway. The magnetic material of the magnetic head is mainly used for the magnetic core, and oxide magnetic materials such as ferrite are known as typical magnetic materials. This oxide magnetic material has a saturation magnetic flux density of about 5000 Gauss, so the coercive force is 10
There is a drawback that sufficient recording cannot be performed on a high retention force recording medium exceeding 0.00 erted.

Therefore, magnetic heads using metallic magnetic materials with high saturation magnetic flux density, such as Sendust, for the magnetic core have been considered, but when such metallic magnetic materials are used in magnetic heads, they suffer from eddy current loss in the high frequency region. However, there was a drawback that the reproduction sensitivity was reduced.

Since magnetic heads using a single magnetic material for the magnetic core have various drawbacks, a magnetic head using a composite magnetic material as shown in FIG. 5 has been proposed. This magnetic head uses a laminated composite magnetic material for the magnetic core, and a metal magnetic core 11 made of sendust is sandwiched between oxide magnetic cores 12 made of ferrite to compensate for magnetic properties in the high frequency range. , the configuration is designed to improve playback flexibility. The metal magnetic core 11 and the oxide magnetic core 12 are joined using a limited solder.

However, the magnetic material used for such a magnetic core requires a step of sandwiching and bonding the metal magnetic core 11 between a plurality of oxide magnetic cores 12, which has the disadvantage of reducing bonding strength and significantly hindering mass production.

[Purpose of the invention]

The present invention was made in view of the above circumstances, and its purpose is to improve the joint strength of a composite magnetic material made by joining a metallic material and an oxide magnetic material, and to improve mass production. The aim is to enhance sexuality.

[Embodiments of the invention]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a perspective view of a composite magnetic material according to the present invention. In FIG. 1, 1 is an oxide magnetic material block such as ferrite, 2 is a metal magnetic material block such as sendust, and 3 is a metal magnetic thin film such as sendust interposed between the oxide magnetic material block 1 and the metal magnetic material block 2. It is formed on the outer surface of the oxide magnetic material block 1 by thin deposition, sputtering, or other means. The metal magnetic thin film 3 and the metal magnetic material block 2 are joined by brazing, such as silver soldering, to form a composite magnetic material block consisting of the oxide magnetic material block 1 and the metal magnetic material block 2.

Next, to explain the manufacturing method of the above composite magnetic material (block), first, as shown in FIGS. 2(a) and (b), one side of the oxide magnetic material block 1 and the metal magnetic material block 2 is Process it to a mirror surface using dia polish, etc. Next, a metal thin film 3 having the same components as the metal magnetic material block 1 is formed on the mirror-finished surface of the oxide magnetic block 1, and this metal magnetic thin film 3 and the metal magnetic material block 2 are
A composite magnetic material block can be obtained by joining the mirror-finished materials by means such as brazing.

Generally, it is extremely difficult to bond sendust to ferrite and other dissimilar magnetic materials, but by forming a metal magnetic thin film on the oxide magnetic material that makes up the composite magnetic material, it is possible to bond the oxide magnetic material and the metallic material. It is possible to make the bond with high strength.

FIG. 4 is a perspective view of the composite magnetic material shown in FIG. 1 used in the magnetic core of a magnetic head. By applying this, a magnetic core can be obtained. This magnetic core includes a rear core 1a made of an oxide magnetic material and a front core 2a made of a metal magnetic material forming a magnetic gap.
It consists of By adopting such a configuration, eddy current loss in the high frequency region is reduced, and an increase in regeneration intensity can be expected.

In the above embodiment, the metal magnetic material (block) 2
Although it has been described that the material and the metal magnetic thin film 3 are made of the same material, any metal magnetic material may be used. That is, when the metal magnetic material 2 is Sendust, the metal magnetic thin film 3 can be made of a metal material such as Permalloy or Alperm as well as the same type of Sendust.

Furthermore, as an example of using the composite magnetic material of the present invention in the magnetic core of a magnetic head, the configuration of the magnetic core as shown in FIG. It is also possible to apply it to a magnetic core configuration (laminate core).

〔Effect of the invention〕

As explained above, according to the present invention, in a composite magnetic material in which a metal magnetic material is bonded to an oxide magnetic material, the metal magnetic material is bonded to the oxide magnetic material. The material and the metal magnetic material can be easily joined together, and the strength of the joint can be increased.

[Brief explanation of drawings]

FIG. 1 is a perspective view of a composite magnetic material according to the present invention, FIGS. 2 and 3 are diagrams explaining a method for manufacturing the composite magnetic material of the present invention, and FIG. 4 is a perspective view of a composite magnetic material according to the present invention. FIG. 5 is a perspective view of a magnetic core using a conventional composite magnetic material. 1... Oxide magnetic material, 2... Metal magnetic material, 3.
...Metal magnetic thin film. Patent applicant: Pioneer Corporation
Hideo Takino Figure 1 Figure 2 Figure 3

Claims (1)

[Claims] A composite magnetic material in which a metal magnetic material is bonded to an oxide magnetic material, characterized in that a metal magnetic thin film is formed on the oxide magnetic material, and the metal magnetic material is bonded to the metal magnetic thin film. Composite magnetic material.