JPS61194611A - Manufacture of magnetic head - Google Patents

Abstract

PURPOSE:To eliminate such necessity that silver brazing filler metal being nonmagnetic material is used by diffusion-jointing two core bodies made of 'Sendust(R)' alloy by HIP processing so as to manufacture a magnetic head. CONSTITUTION:A coil window 3 is formed at the joint surface side of either one of the core bodies 1 and 2 made of 'Sendust(R)' alloy, and at some part of the core body an SiO2 film 4 is formed. Two core bodies 1 and 2 are contained in a can 5 made of soft steel in the state where their joint surfaces are batted, covered by vacuum packing, set to an HIP processor and subjected to the HIP processing, which is hot static pressure pressurizing processing. It employs an inert gas such as argon as a pressure medium and executes the pressurizing processing by utilizing the synergistic effects of high temperature and high pressure. For instance, the core bodies 1 and 2 are placed on a specimen stand 11 in the state where they are sealed in the can 5 made of soft steel. Then a compressor 14 and a heater 13 are driven to keep a hermetically sealed space A in such an atomosphere as several hundreds of atmospheric pressure and about 1,200 deg.C, which is maintained about 1hr.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of manufacturing a magnetic head made of a centast alloy mainly used for recording and reproducing metal tapes.

As for differential skin delta skin direct magnetic heads, those using conventional ferrite cores are not compatible with metal tapes that achieve high recording densities. A magnetic head made of an alloy is used.

By the way, a magnetic head is formed by joining two core bodies to form a magnetic gap and a coil, but when the core body is made of centast alloy, it has poor compatibility with glass.
Unlike ferrite heads, it cannot be bonded with glass, so currently silver solder is used for bonding.

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However, since silver solder is a diamagnetic material, when two core bodies are joined using silver solder, the silver solder diffuses into the joint surface of the core bodies, causing the following problem.

That is, the magnetic circuit of the magnetic head consists of two core bodies, a back gap which is a joint surface between both core bodies, and a tape recording area.
Since it is composed of a series circuit of four magnetic resistances with the front gap, which plays the main role in reproduction, the diffusion of diamagnetic silver solder into the front gap and pack gap greatly increases the magnetic resistance of the magnetic circuit. There is a problem in head performance that the good hysteresis characteristics such as high magnetic permeability and high saturation magnetic flux density characteristics of the centast alloy cannot be utilized, and the magnetic characteristics of the head deteriorate.

Therefore, in order to solve this problem, the present invention provides a new and useful method for manufacturing a magnetic head that can bond a core body made of centast alloy without using any silver solder, which causes deterioration of the magnetic properties of the head. is intended to provide.

In order to achieve the above object, the method for manufacturing a magnetic head according to the present invention involves HIPing two core bodies made of a centast alloy.
It is characterized by expansion bonding through processing.

Takumi Ushiki FIG. 1 shows a core body 1.2 made of Centast alloy.

Each core body 1.2 is a centast alloy block with winding grooves, winding windows, etc. processed, and after joining these core bodies 1.2, it can be sliced into a piece with a thickness of about 0.15 mm. Cores used in magnetic heads are obtained. A winding window 3 is formed on one side of the core body on the joint surface side, and
A 5i02 film 4 is formed in a part. This film 4 is a gap spacer for forming a front gap at a predetermined distance when the two core bodies 1.2 are joined.

The above-mentioned two core bodies 1.2 are housed in a mild steel can 5 with their joint surfaces butted and in contact as shown in FIG. 2, covered with a vacuum backing, and subjected to HIP treatment as shown in FIG. It is set in the device and subjected to HIP processing. Here, HIP processing refers to Hot Is.

5tatic Pressing (hot isostatic pressing)
Abbreviation for processing, using an inert gas such as argon as a pressure medium,
This is a pressure treatment technology that utilizes the synergistic effect of high temperature and high pressure.

The H[P processing apparatus shown in FIG. It consists of a sample heating heater 13 provided in a space A within the space A, and a compressor 14 for introducing a pressure medium such as argon gas into the space A. Although not shown, the upper lid 10a and the lower lid 10c are held from the outside by a press frame.

To join two core bodies 1.2 with this HIP device,
The core body 1.2 is sealed in a mild steel can S and placed on the sample stage 11, and the compressor 14 and heater 13 are driven to maintain the inside of the closed space A at several hundred atmospheres and an atmosphere of about 1200°C. , and maintain this for about 1 hour.

If the core bodies 1.2 are placed under the above conditions, the two core bodies 1.2 are pressed under high pressure and simultaneously heated to a high temperature, which increases the movement of atoms, so that atoms are removed from the joint surface. Interdiffusion takes place and the two core bodies 1.2 are directly joined.

When the bonding is completed, the magnetic head core is taken out from the HIP processing equipment, the mild steel coating 5 is removed, and the magnetic head core base with the two core bodies 1.2 bonded is sliced thinly to a thickness of about 0.15 mm. obtain.

As explained above, according to the present invention, since a magnetic head is manufactured by diffusion bonding two core bodies made of centast alloys by HIP processing, silver, which is a diamagnetic material, is There is no need to use wax at all, so the magnetic resistance of the magnetic circuit of the magnetic head is reduced, and the excellent properties of Centast alloy, such as high magnetic permeability and high saturation magnetic flux density, are effectively utilized, resulting in effective magnetization. This has the remarkable effect of making it possible to obtain a magnetic head with unique characteristics.

[Brief explanation of drawings]

Figure 1 is a perspective view showing two core bodies, Figure 2 is a diagram showing the two core bodies housed and covered in a mild steel can prior to HIP processing, and Figure 3 is a view of the HIP processing equipment. It is a figure showing a schematic structure. 1.2... Core body, 10... HIP processing device. Figure 1 Figure 2 Figure 3

Claims (1)

[Claims] A method of manufacturing a magnetic head, characterized in that two core bodies made of a centast alloy are diffusion bonded by HIP processing.