JPS6355131B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a composite magnetic head having a core made of different types of magnetic materials bonded together, and a method for manufacturing the same.

Conventionally, ferrite has generally been used as a magnetic head material for high frequencies. Ferrite not only has excellent electromagnetic properties at high frequencies, but also
It has the characteristic that there is little wear due to contact with the recording medium. However, the saturation magnetic flux density B _S is about 5500 Gauss for ferrite that can actually be used, so when recording on a high coercive force recording medium with a narrow gap magnetic head, the gap part becomes magnetically saturated. , there is a problem that recording efficiency decreases. In addition, magnetic heads using ferrite materials inherently have a lot of noise and do not have good S/N.
There are limits to obtaining ratios.

On the other hand, metal magnetic materials such as Fe-Ni alloy,
Fe-Al-Si alloy (sendust) has a saturation magnetic flux density much higher than that of ferrite, and has a high initial magnetic permeability, so it is often used as a magnetic core for ordinary heads. In addition, recently developed amorphous metal magnetic materials are attracting attention as magnetic head materials for high-density magnetic recording.

However, since the magnetic head made of the above metal magnetic material alone has low electrical resistance, high frequency loss is large and magnetic permeability decreases at high frequencies. To prevent this, a magnetic core material made of thin plates and laminated is used, but the technique for laminating thin plates is difficult and the adhesive part spreads due to sliding with the recording medium. It was hot.

A magnetic head that eliminates the above-mentioned drawbacks is a composite magnetic head made of different materials, in which a material with good workability such as ferrite is used for the rear magnetic core of the magnetic head, and a metal magnetic material is bonded only to the tip facing the recording medium. is proposed. However, these magnetic heads were bonded with resin or the like, and were unreliable in terms of performance and strength. In other words, when an organic polymer material is used to join a rear magnetic core made of ferrite and a tip made of a metal magnetic material, (i) the mechanical bonding strength is low, and for example, when cutting into a desired shape, the joint (ii) The thickness of the adhesive layer is not uniform enough to easily cause variations in the characteristics of the magnetic head;
(iii) After bonding, the shape of the adhesive layer changes slightly due to changes in environmental temperature and humidity, causing slight fluctuations in the relative positional relationship between the bonded magnetic materials, which may cause variations in the characteristics of the magnetic head. There were some difficulties.

Also, attempts have been made to bond glass by melting it, but this requires high-temperature heating, and especially in the case of amorphous materials, crystallization occurs, resulting in deterioration of magnetic properties. On the other hand, it is difficult to bond sendust to ferrite using molten glass.

Therefore, it can be said that a highly reliable method for manufacturing a junction type magnetic head using different materials has not been obtained.

The purpose of the present invention is to solve the above-mentioned difficulties of the prior art,
The present invention provides a composite magnetic head with excellent characteristics and a method for easily manufacturing the same, especially when the front magnetic core is made of a ferromagnetic amorphous alloy or Fe-Al.
-The rear magnetic core is made of Si alloy (Sendust).
The object of the present invention is to provide a composite magnetic head with excellent characteristics made of Mn--Zn ferrite or Ni--Zn ferrite, and a method for easily manufacturing the same.

In order to achieve the above object, the composite magnetic head of the present invention has a magnetic core having a structure in which a front magnetic core and a rear magnetic core having a predetermined shape are in contact with each other. A magnetic core consisting of a magnetic core block in which both magnetic cores are joined by applying a voltage between the two magnetic cores at a high temperature within a range that does not soften either the magnetic cores or the intermediate film. It has the following.

Further, the method for manufacturing a composite magnetic head of the present invention includes: (i) on at least one surface of the front magnetic core body and the rear magnetic core body each having a predetermined shape to be joined to each other;
(ii) forming an intermediate film made of at least one material selected from the group consisting of an insulator and a conductor;
a step of juxtaposing the front magnetic core and the rear magnetic core in a state of surface contact with each other via the intermediate film on the surfaces to be joined, and (iii) bringing the front magnetic core into contact with each other; A step of joining the rear magnetic core and the intermediate film by applying a voltage between the two magnetic cores while heating the rear magnetic core to a high temperature that does not soften the two, and if necessary, After producing the left or right magnetic core block in the process up to (iii), further (') repeating steps (i) to (iii) to form the remaining right or left magnetic core block;
and (') joining the left and right magnetic core blocks at the surfaces to be joined to each other.

First, the principle of the method for joining magnetic materials used in the present invention will be explained with reference to FIG.

As shown in FIG. 1, a conductive material (metal) 10 and an insulating material (glass) 11 are butted against each other and heated, and a high voltage 12 is applied between the metal 10 and the glass 11.
Bonding is performed by adding .

By heating, the glass 11 starts to behave as an electrolyte, and the specific resistance becomes smaller.
Promotes the formation of a space charge layer. When a high voltage is applied to this, the mobile ions (M) move to the cathode side, and a depletion layer of mobile ions is created on the anode side, causing polarization. The electric field in the depletion layer is extremely large, 4×10 ⁶⁰ V/
cm, and the electrostatic attraction force acting between the metal electrode and the glass is 70Kg/ ^cm2 . Positive metal ions are supplied to the glass from the anode, and these positive ions drift through the depletion layer and neutralize fixed negative ions (O).
On the other hand, fixed negative ions (O) in the glass move toward the anode. This ion transport determines the bonding process and is dependent on the glass/metal combination and temperature.

The method according to the invention uses the above bonding principle to
After forming an intermediate film made of an insulator, a conductor, or both on the joint surfaces of two types of magnetic materials to be joined, the two types of magnetic materials are butted together and heated while being heated.
This method is characterized in that by applying a voltage between the two magnetic materials, the two can be easily joined.

The magnetic head manufactured by the method of the present invention is
The front magnetic core (the magnetic core closest to the recording medium during operation) is made of a magnetic material with high saturation magnetic flux density, such as a highly conductive magnetic material such as a ferromagnetic amorphous alloy or sendust, and the rear magnetic core (the one closest to the recording medium during operation) (Sometimes, the magnetic core that is far from the recording medium) is made of a low-conductivity magnetic material with excellent high-frequency characteristics, such as Mn-Zn ferrite or Ni-
The main type of head is a well-known composite magnetic head using Zn ferrite, but it is not limited to these magnetic materials. All magnetic heads use a core. In this way, a magnetic head that has a core made by using different magnetic materials for the front and rear parts and bonding them together can take advantage of the different characteristics of each material, allowing more freedom in the design of the magnetic head. Although it is expected that novel configurations will continue to appear in the future, the present invention can be applied to both existing and future composite magnetic heads.

The above-mentioned well-known composite magnetic head is described, for example, in Japanese Patent Publication No. 39-28374.

As mentioned above, the material constituting the front magnetic core is a material with high saturation magnetic flux density, and is generally Fe-Al.
-Si-based alloy (so-called sendust) or ferromagnetic amorphous alloy is used. The former is 3-10% by weight
(Hereinafter, only % indicates weight %) Al, 6~
It has a basic composition of 12% Si and the balance Fe, and it is currently known that various additive elements are added to this.
The amount of Al, the amount of Si, or both may be slightly different from the above composition. The latter is proposed, for example, in patent publications JP-A-51-65395 and JP-A-51-73920, namely, combinations of one or more elements of Fe, Ni, Co, and P, C, B, and Si. An alloy consisting of one or more elements, or having this as the main component,
Al, Ge, Be, Sn, In, Mo, W, Ti, Mn, Cr,
An alloy containing Zr, Hf, Nb, etc. is melted and rapidly quenched to form a tape with a thickness of about 20 to 100 μm. However, it goes without saying that other ferromagnetic amorphous alloys with high magnetic permeability and saturation magnetic flux density can also be used.

The high permeability material constituting the rear magnetic core is a low conductive magnetic material in order to improve high frequency characteristics and reduce eddy current loss. Although Mn--Zn ferrite or Ni--Zn ferrite is commonly used as such a material, other materials can be used as long as they have high magnetic permeability and low electrical conductivity.
The ferrite may be used in either a single crystal or polycrystal form.

As the intermediate film, an insulating film or a conductive film is used, or both can be used to form a multilayer structure. For example, glass or ceramics can be used as the insulating film. In particular, a glass containing Na, K, B, Ca, Mg, etc. that becomes a high electrolyte when heated is preferable, and a glass that causes polarization at a relatively low temperature when a high voltage is applied is preferable. For example, soda lime glass, carbonated soda lead glass,
Various types of borosilicate glasses are used. Examples of the conductive film used for the intermediate film include Al, Fe, Ni, Co,
Examples include Cu, Zn, Sn, In, Pb, Ti, Cr, Mo, Si, and alloys thereof.

Generally, the insulating film is formed by sputtering, and the metal film is usually formed by vacuum evaporation and sputtering.

The thickness of the intermediate film is preferably 0.1 to 3 μm.
If it is thinner than 0.1 μm, dielectric breakdown may be exceeded when a voltage is applied. If it exceeds 3 μm, the loss of magnetic flux during operation of the magnetic head will increase, which is not preferable.

The intermediate film may be a single layer, but it is also possible to have multiple layers. In the case of multiple layers, it may be only an insulating film or only a conductive film, but it is best to mix them and take advantage of their respective strengths. There are many things. That is, when the intermediate layer is an insulating film, it is deposited on the low conductive side, that is, the rear magnetic core made of ferrite, for example, and then the front part made of a high conductive magnetic material such as Fe-Al-Si alloy. Good results can be obtained by bonding the bonding surface of the magnetic core and the insulator film serving as the intermediate film by the method described above. This is because when attaching an insulating film, it is often better to use a low conductor as the other side, and when bonding by applying a voltage at high temperature, it is better to have one of the bonding surfaces be a high conductor. This is thought to be due to the fact that ions are easily supplied and bonding is often easy. In addition, when the intermediate film is a conductive film such as Al, it should be placed on the high conductive side, that is, for example
After adhering to the front magnetic core made of Fe--Al--Si alloy, the joint surface of the rear magnetic core made of a low-conductivity magnetic material such as ferrite and the conductive film as the intermediate film are bonded by the method described above. Conversely, if a conductor film is applied to the low conductor side, the bonding surface will be
It becomes a bond between conductors like Si alloy and Al,
This is because, as described above, even if a voltage is applied at high temperatures, the bonding surface does not become a polarized surface and the bondability is low. Considering these characteristics of each intermediate film, in the case of an intermediate film consisting of two layers, an insulator film and a conductor film, the former is deposited on the low conductive magnetic material side, that is, the rear magnetic core, and the latter It is generally desirable to adhere the material to the high conductive magnetic material side, that is, to the front magnetic core, and to bond the two together using the method described above (the method of bonding while applying a voltage at high temperature). Furthermore, by forming the interlayer film into multiple layers in this way, the degree of freedom in selecting materials with good compatibility increases, making it easier to obtain more favorable results.

Note that it is desirable to select a more appropriate intermediate film depending on the material constituting each magnetic core.

In step (ii), when both magnetic cores are juxtaposed in a state of surface contact at their joining surfaces, the next step (iii)
Since the electrostatic attraction force can be utilized, there is no need to use particularly high pressure to press the two surfaces together, and it is sufficient to simply maintain the state of surface contact. As shown in the embodiment described later, both magnetic cores may be held in surface contact by a jig that also serves as an electrode for voltage application.

The heating temperature in step (iii) is determined depending on the type of insulating film or the change in temperature characteristics of the magnetic material, but is generally in the range of 150°C to 800°C.

Magnetic materials that require special attention are amorphous metals, and bonding must be performed at a temperature below the crystallization temperature. Generally, the temperature is preferably 400°C or lower, and the insulating film used in combination with this is suitably soft glass, and the temperature is 150°C to 400°C. The applied voltage ranges from several hundred volts to one thousand volts.
Since the current density decreases as the bond progresses from a value ranging from 2 μA to 50 μA/mm ² or more to a very small value, no specific value can be stated. The higher the voltage and the corresponding current, the shorter the time required, and vice versa. In practice, the current density is generally 3 to 20 μA/mm ²
The time range is from several minutes to several tens of minutes. Including the time for raising and lowering the temperature, it takes about 20 minutes to 1 hour.

In addition, what is generally called solder glass is used as the above-mentioned soft glass. Its commonly used composition is PbO-containing;
SiO ₂ system, PbO−B ₂ O ₃ system, PbO−B ₂ O ₃ −SiO ₂ −
Al ₂ O ₃ system, PbO−B ₂ O ₃ −SiO ₂ system, PbO−B ₂ O ₃ −
There are ZnO series, ZnO-B ₂ O ₃ series, ZnO-B ₂ O ₃ -V ₂ O ₅ series, etc.

As mentioned above, when joining amorphous alloys,
Among the above types of glasses, the softening temperature is 600 to 650℃
The following glasses are suitable, and these glasses can be used at temperatures of 150 to 500℃ (however, in the case of joining amorphous alloys,
Bonding is performed by applying voltage at temperatures below 400°C.

On the other hand, in the case of Fe-Al-Si alloys or ferrites, the heating temperature range is wide, and high melting point glasses, ceramics, and metals can be used. For such materials, a heating temperature of 300°C to 700°C is suitable. However, in any case, the upper temperature limit is below the softening point of the glass film serving as the intermediate film, or below the melting point of the metal film (also referred to as the softening point). The applied voltage is preferably 300 to 3000V. The current density and bonding time are almost the same as in the case of the amorphous alloy described above.

Therefore, the bonding conditions in step (iii) are that the applied voltage is several hundred V to 1,000 V, the current density is 2 to 50 μA/mm ² ,
Generally, the bonding time is several minutes to several tens of minutes, and the required time including temperature rise and fall time is about 20 minutes to 1 hour, but depending on the material combination and heating temperature, appropriate voltage and current conditions (polarity and ), bonding times may vary slightly. If necessary, it is preferable to determine it by experiment with reference to the above numerical values.

Note that in most cases, the power source is a DC power source, but it may also be a pulsating DC power source, or in some cases, a low frequency AC power source.

Through the process including each step up to step (iii) described above, a block corresponding to half of the core of the composite magnetic head (core half), that is, a block in which the core is divided into left and right parts with the working gap forming surface as the border, is produced. One of the left and right magnetic core blocks is completed. In step ('), the same blocks as steps (i) to (iii) are repeated to produce a magnetic core block corresponding to the remaining half of the core. In reality, there are steps of mirror-finishing the surface including the gap surface and forming coil winding grooves for either the left or right block.

In step ('), the left and right magnetic core blocks are joined at the surfaces to be joined together, that is, the surfaces including the working gap forming surface;
Fabricate the core of the composite magnetic head. Further, a coil is wound around the winding window to form a composite magnetic head. If necessary, cylindrical polishing is performed on the surface facing the magnetic recording medium.

The left and right magnetic core blocks may be joined by a method used in the prior art, but it is more preferable to provide an intermediate layer between the joining surfaces, as in the case of joining the front and rear magnetic cores. Then, both surfaces are brought into contact via an intermediate layer, and a voltage is applied between the left and right magnetic core blocks at high temperature to join them together. The details are the same as the explanation for joining the front magnetic core and the rear magnetic core, but since the joining in step (') is a joining between the same type of materials, the intermediate layer can be attached to either the left or right magnetic core block. It is not a particular problem as to the bonding technique whether it should be adhered or not, and it may be applied in a manner convenient for the work. It should be noted that since the joining in step (') is performed at the same time as the formation of the working gap, part of the joining surfaces will be joined via the working gap. It is usually convenient for this working gap to also serve as the joining intermediate layer.

However, the most characteristic part of the present invention lies in the joining of the front magnetic core and the rear magnetic core, and the parts corresponding to the above steps (') and (') are as follows:
Any other suitable process may be used, and the effects of the present invention can also be expected in that case. If there is a method for producing the core of a composite magnetic head without using a core semiconductor, that method may be used. In short, it can be said that the essence of the present invention is to use the above-described joining method of the present invention for joining different magnetic materials of a composite magnetic head.

The composite magnetic head of the present invention disclosed above has the following features:
Since the bonding between the magnetic cores is done at a low temperature, there is no disadvantage due to exposure to high temperatures, and the bonding strength is sufficient.
This is an excellent product with very little variation in characteristics, and an excellent composite magnetic head can be easily manufactured by the method of the present invention.

Hereinafter, the present invention will be explained in more detail with reference to Examples.

Example 1 Magnetic head configuration block 1 as shown in FIG.
3, 14 and the interlayer film 15 as a composite unit. Block 13 corresponds to the front magnetic core, and block 14 corresponds to the rear magnetic core. Block 13 is an Fe--Al--Si metal magnetic material, and block 14 is Mn--Zn ferrite. Fe-Al-Si alloy (sendust) contains 85% Fe, 5.4% Al, and Si.
A composition of 9.6% was used, and the Mn-Zn ferrite contained 54 mol% of Fe ₂ O ₃ , 27 mol% of MnO,
A composition containing 19 mol% of ZnO was used.
The Mn-Zn ferrite used in the present invention usually has a composition of 40 to 66 mol % Fe ₂ O ₃ , 10 to 50 mol % MnO, and 5 to 35 mol % ZnO.

The thickness of the block 13 made of sendust is approximately 1
mm, and was ground in a later step so that the thickness near the operating gap was approximately 50 μm. usually,
This thickness is in the range of 10 to 100 .mu.m, which is often approximately the same as the working gap depth, and may be bonded to the ferrite block 14 using a thin magnetic material from the beginning. The thickness of the front magnetic core near the operating gap is generally 10 to 100 .mu.m even in the case of materials other than sendust. If it is less than 10 μm, the life will be shortened due to wear caused by sliding with the magnetic recording medium, and if it exceeds 100 μm, loss due to eddy current will increase, and high frequency characteristics, especially
High frequency characteristics deteriorate at frequencies above 4MHz.

When joining the above two blocks to each other,
A glass film 15 of about 0.5 μm is deposited as an intermediate insulating film on the joint surface of the Mn--Zn ferrite block 14 by sputtering. Naturally, the abutting surfaces of the blocks 13 and 14 are mirror polished. Such constituent blocks are arranged as shown in FIG. In other words, the constituent blocks are a conductive block (metallic magnetic material) 13 and an insulating film (glass film) 15.
and a ferrite block 14 having relatively low conductivity. Blocks 13, 14 are heated so that glass membrane 15 becomes more conductive.

Glass film 15 is commercially available soda lime glass.
For #0800 (#0800 is a trade name of Corning Glass Works, USA), the preferred heating temperature range is 300°C to 650°C. For soft glass,
This temperature ranges from approximately 150°C to 500°C, and for quartz glass this temperature is in the higher range of 600°C to 1000°C. In all cases, the upper limit is below the softening point of this particular glass. Heating may be performed in any suitable manner, for example via a support 16 made of stainless steel. The support base 16 is also an electrically conductive piece that becomes an electrically resistive heating piece connected to a power source via terminals 22,23. Other means may also be used, such as electric induction or insertion into the furnace.

The composition of the above glass #0800 is 72.5% _SiO2 ,
Al ₂ O ₃ 4.7%, CaO 7.0%, MgO 2.3%,
It consists of 11.5% Na ₂ O and 2.1% K ₂ O.

A voltage is then applied across this composite unit. That is, by means of a power source 24 having terminals 21 connected to the metal support 16 at portions 19 . power supply 2
The other terminal 20 of 4 is connected to the metal magnetic block 13 via the terminal 18 of the upper metal support 17 made of stainless steel. The terminal 18 may be brought into direct contact with the metal magnetic block 13. In most cases the power source is a direct current power source, but it may also be a pulsating direct current power source or, in some cases, an alternating current power source, particularly at low frequencies. When using a DC power source, it is preferable to make the terminal 18 positive.

The applied voltage, current density and time are not limited and may be varied within a wide range. Generally from 500V
A range of 1200V is preferred. Current density is 2~
The range is 50 μA/mm ² and the time is between 5 and 30 minutes.

Specifically, FIG. 8 shows the relationship between time and current density when an experiment was conducted using soda lime glass #0800 as an interlayer film, heating temperature was 400° C., and applied voltage was 600V and 900V. Curve 34 shows the case when the test was performed at 600V, and curve 35 shows the case when the test was performed at 900V. Bonding is completed in a shorter time when performed at a higher voltage, and the current density is also slightly higher.

The time required for bonding is the time to the bending point at which the current density decreases gradually in FIG. 8, that is, approximately 22 minutes for curve 34 and approximately 22 minutes for curve 3.
In the case of 5, approximately 16 minutes is quite sufficient. However, in practice, the time to the maximum point of each curve, that is, approximately 13 minutes for curve 34, and approximately 13 minutes for curve 3
In the case of No. 5, bonding is possible even in about 4 minutes. Further, although there is no particular problem in applying the voltage at a high temperature beyond the time required to reach the bending point, it may not be preferable in terms of cost to make the voltage application time too long.

The composite unit block joined as described above is then processed according to the magnetic head processing process. First, as shown in FIG. 5, two rectangular parallelepiped blocks 26 and 27 are made, and the surfaces 29 and 30, which include the working gap forming surfaces of the magnetic head, are mirror-polished. Then, a coil winding groove 28 is formed in at least one of the rectangular parallelepiped blocks. At this time, in the rectangular parallelepiped blocks 26 and 27 (these correspond to the left and right magnetic core blocks), the metal magnetic body 13 side is made to be the surface facing the recording medium, and the Mn-Zn ferrite block 14 side is made to be the rear magnetic circuit. I will make it happen.

Next, an insulator that will become the intermediate layer 31 is deposited on one of the surfaces 29 and 30 of the rectangular parallelepiped blocks 26 and 27 including the working gap forming surface by sputtering to a thickness equal to the working gap (approximately 0.5 μm). .
The insulating film may be the same as the intermediate insulating film 15 used for the bonding shown in FIG. 2, or may be made of a different material depending on the case. Preferably, a material having a softening temperature equal to or lower than that of the intermediate insulating film 15 used for the bonding shown in FIG. 2 is used. at least,
The intermediate film 15 is heated at the temperature used to form the working gap.
Preferably, the material does not soften or melt.

In this example, ZnO; 27%, Na ₂ O; 8
%, BaO; 8%, SiO ₂ ; 16%, Al ₂ O ₃ ; 4%, and B ₂ O ₃ ; 37%. This glass has a softening temperature of 600°C and a coefficient of thermal expansion of 74×10 ^-7 deg ^-1 .

Next, the rectangular parallelepiped blocks 26 and 27 are butted and the sixth
Arranged as shown, the composite units are heated in a manner similar to that described in FIG. 3 and bonded together by applying an electrical potential to form the working gap. At this time,
Connect the side on which the insulator film is formed to the negative power supply.

Note that the conditions such as heating temperature, applied voltage, and current density in this case are as described in block 13 and block 1 above.
This is the same as when joining 4.

The magnetic head component block thus produced is cut into magnetic head core units to obtain a composite magnetic head core 33 shown in FIG. The composite magnetic head core has a coil wound around the coil winding window 32 to form a magnetic head. (The diagram shows only the core and omits the coil.) If necessary, the magnetic tape sliding surface is polished into a cylindrical shape.

The composite magnetic head manufactured in this manner does not cause peeling of the bonded portion even when cut, the thickness of the adhesive layer is uniform, there is almost no variation in characteristics, and there is no change in characteristics after manufacturing. This is completely unacceptable, and is extremely superior to conventional composite magnetic heads.
Further, by the manufacturing method of the present invention, this excellent composite magnetic head could be easily manufactured.

In the above embodiment, two bonding steps are used, but depending on the type of magnetic material, a composite magnetic head can be made by performing one of the bonding steps using a different bonding method.

Embodiment 2 In FIG. 2, an amorphous metal magnetic material is used as the magnetic head constituting block 13, and a block 14 combined therewith is made of Mn--Zn ferrite. In this case, care must be taken when joining at a temperature below the temperature at which the amorphous metal magnetic material crystallizes. The crystallization temperature of amorphous metal magnetic materials varies depending on the material composition, but for example, in the Fe-Co-Si-B system, it is approximately 400
The limit is ℃. Therefore, it is necessary to select an intermediate insulating film that can be bonded by applying a voltage at a heating temperature of 400° C. or lower. The material chosen for the glass is a material that has a relatively low softening temperature of 700°C or less and easily becomes an electrolyte when heated.

In this example, an amorphous metal magnetic material (Fe _0.06
Co _0.94 ) ₇₄ Cr ₂ Si ₁₆ B ₈ was used, and the molar composition ratio Fe ₂ O ₃ ; 53%, MnO; 28%, as Mn-Zn ferrite.
Using ZnO; 19%, SiO ₂ 53% as glass,
_Al2O3 ; 0.8% _, CaO; 21%, PbO; 30%,
Na ₂ O; 3.5%, K ₂ O; 10.3%, softening temperature: 620°C,
A material with a coefficient of thermal expansion of 98×10 ^-7 /°C was selected. This intermediate glass film was deposited to a thickness of about 1 μm on the Mn-Zn ferrite side by sputtering. After the above composite units were butted and arranged as shown in FIG. 3, heating and potential application were carried out as in Example 1. In this case, the amorphous metal magnetic body 13 side was connected to the positive terminal of the power source 24, and the Mn--Zn ferrite block 14 side was connected to the negative terminal. The heating temperature was approximately 350°C, and the applied voltage was 600V. Current density is 3~5μA/
It was warm in ^mm2 . The bonding time in this case was approximately 20 minutes.

Furthermore, it was possible to bond in several hours at a temperature of 150°C, and in a few minutes at a temperature of 400°C.

The composite magnetic head manufactured in this way has a front magnetic core made of an amorphous alloy, which takes advantage of the characteristics of an amorphous alloy. A composite magnetic head using a crystalline alloy could be easily manufactured.

Example 3 In FIG. 4a, block 13 is made of Fe-Al-
A Si-based metal magnetic material is used, and the block 14 is made of Ni-
Zn ferrite was used. In this case, the joint surface of one block 13 (i.e., metal magnetic material) is
Al was deposited to a thickness of 0.5 μm by vacuum evaporation, and the blocks 14 were bonded. Block 13 Fe-Al
-Si alloy has the same composition as used in Example 1. The Ni-Zn ferrite used in block 14 had a composition of 17.5 mol% NiO, 32.4 mol% ZnO, and 50.1 mol% Fe ₂ O ₃ .

The purpose of this example is to provide a metal intermediate layer 2 on the metal magnetic material side.
5 increases the bonding strength and is also useful in lowering the bonding temperature. The joining method was the same as in Example 1, and the heating temperature was 400°C.
The voltage applied between both blocks was 800 V, the current density was 10 μA/mm ² , and the bonding time was 20 minutes. The interlayer film is not particularly limited, but may include Al, Ni, Fe,
Good results were obtained with Co, Cu, Ti, Cr, Mo, and Si.
The other steps were the same as in Example 1 to produce a composite magnetic head. The composite magnetic head produced in this way had the same benefits as in Example 1, and was significantly superior to the conventional one.

Furthermore, when an amorphous alloy magnetic material is used as the front magnetic core, Al, Cu, Zn, Sn, In, and alloys thereof are suitable. Also in this case, the magnetic head manufacturing process is the same as described above. In this case as well, the same benefits as in Example 2 were obtained.

Embodiment 4 Another embodiment of the present invention is implemented using the configuration shown in FIG. 4b. A Fe-Al-Si metal magnetic material is used for the block 13, a Mn-Zn ferrite is prepared for the block 14, and a metal film 25 (here,
A glass film (SiO ₂ , 63.1%, Al ₂ O ₃ ; 0.3%, CaO; 0.9%,
PbO; 20.2%, _Na2O ; 7.6%, _K2O ; 5.5%,
About 0.9% Mn ₂ O ₃ was added by sputtering method.
Deposit 0.5 μm. These were butted against each other and joined according to the process of Example 1 to produce a composite magnetic head. Furthermore, as a Fe-Al-Si alloy,
A composition having a composition of Fe: 85%, Al: 6.5%, and Si: 8.5% was used, and the same Mn--Zn ferrite as in Example 1 was used. In the bonding step, the heating temperature was 500° C., the voltage applied between both blocks was 600V, the current density was 5 μA/mm ² , and the bonding time was 15 minutes. A composite magnetic head was produced in the same manner as in Example 1 in other respects. The thus obtained composite magnetic head and its manufacturing method had the same benefits as in Example 1.

Similarly to this embodiment, suitable bonding conditions can be selected from a wide range even if the combination of magnetic materials changes.

Although typical examples of the present invention have been shown above, the shape of the composite type may be different, and it is also possible to join magnetic materials of the same type. The intermediate film may be formed by methods other than sputtering and vapor deposition. Further, the intermediate film may be a multilayer film.

As explained above, according to the present invention, low-temperature bonding is possible without melting or softening an insulating material such as glass, and in particular, by bonding through an intermediate film, the crystal temperature of an amorphous metal magnetic material can be lowered. Since bonding can be performed in the following steps, a magnetic head capable of high-density magnetic recording can be easily manufactured without deteriorating performance.

In addition, with composite magnetic heads that use sendust or the like on the recording medium side, it is now possible to bond using glass films, etc., which were conventionally considered impossible to bond, without using polymeric resin bonding materials, which have many problems. It has now become possible to manufacture composite magnetic heads with stable and good characteristics without any variation.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram showing the principle of joining magnetic materials in the present invention, FIG. 2 is a bird's-eye view showing the front magnetic core, rear magnetic core, and deposited intermediate film in an embodiment of the present invention, and FIG. 3 4 is an explanatory diagram showing the process of joining both magnetic cores via an intermediate film in an embodiment of the present invention, and FIG. 4a and FIG. FIG. 5 is a bird's-eye view of the left and right magnetic core blocks in an embodiment of the present invention, and FIG. 6 is a side view showing the left and right magnetic core blocks in an embodiment of the present invention joined through an intermediate layer. Explanatory diagram showing the process, No. 7
The figure is a bird's-eye view of a composite magnetic head according to an embodiment of the present invention, and FIG. 8 is a graph showing the relationship between current density and time when magnetic cores are joined. 10... Conductive material, 11... Insulating material, 13...
... Front magnetic core block, 14 ... Rear magnetic core block, 15 ... Intermediate film (glass film), 16 ... Metal support, 17 ... Upper metal support, 22, 23
... Heating power supply terminal, 24 ... Power supply, 25 ... Intermediate film (metal film), 31 ... Intermediate layer, 32 ... Coil winding window, 33 ... Composite magnetic head, 34 ...
When the applied voltage is 600V, 35...the applied voltage is
For 900V.

Claims (1)

[Scope of Claims] 1. In a magnetic head having a magnetic core having a structure in which a front magnetic core and a rear magnetic core of a predetermined shape are in contact with each other, both magnetic cores are brought into close contact with each other via an intermediate film, and both magnetic cores and A composite type characterized by having a magnetic core consisting of a magnetic core block in which both magnetic cores are joined by applying a voltage between the two magnetic cores at a high temperature within a range in which neither of the intermediate films softens. magnetic head. 2. The composite magnetic head according to claim 1, wherein the front magnetic core is made of a highly conductive magnetic material, and the front and rear magnetic cores are made of a low conductive magnetic material. 3 The front magnetic core is made of a ferromagnetic amorphous alloy or
2. The composite magnetic head according to claim 1, wherein the magnetic head is made of a Fe--Al--Si alloy, and the rear magnetic core is made of Mn--Zn ferrite or Ni--Zn ferrite. 4. The composite magnetic head according to claim 1, 2, or 3, wherein the intermediate film is an insulating film. 5. The composite magnetic head according to claim 1, 2, or 3, wherein the intermediate film is a conductive film. 6. The composite magnetic head according to claim 1, 2 or 3, wherein the intermediate film comprises at least one insulating film and at least one conductive film. 7. The composite magnetic head according to claim 6, wherein the insulating film is on the rear magnetic core side and the conductive film is on the front magnetic core side. 8. Claim 4, wherein the insulating film is made of glass or ceramics.
7. The composite magnetic head according to item 6 or 7. 9 The conductor film is Al, Fe, Ni, Co, Cu,
The composite type according to claim 5, 6 or 7, characterized in that it is made of at least one element selected from the group consisting of Zn, Sn, In, Pb, Ti, Cr, Mo and Si. magnetic head. 10 The magnetic core brings the left and right magnetic core blocks into close contact with each other via an intermediate layer, and maintains a temperature between the two magnetic core blocks at a high temperature within a range where neither the magnetic core blocks nor the intermediate layer soften. Claims 1, 2, 3, and 4 are characterized in that both magnetic core blocks are joined by applying a voltage to
A composite magnetic head according to item 1, 5, 6, 7, 8 or 9. 11 (i) Forming an intermediate film made of at least one material selected from the group consisting of insulators and conductors on at least one surface of the front magnetic core body and rear magnetic core body having a predetermined shape to be joined to each other. (ii) a step of arranging the front magnetic core and the rear magnetic core on the surfaces to be joined so as to be in surface contact with each other via the intermediate film, and (iii) A step of joining the two magnetic cores by applying a voltage between the two magnetic cores while heating the front magnetic core, the rear magnetic core, and the intermediate film to a high temperature within a range that does not soften them. A method for manufacturing a composite magnetic head characterized by: 12. The method of manufacturing a composite magnetic head according to claim 11, wherein the front magnetic core is made of a highly conductive magnetic material, and the rear magnetic core is made of a low conductive magnetic material. 13 Claims characterized in that the front magnetic core is made of a ferromagnetic amorphous alloy or a Fe-Al-Si alloy, and the rear magnetic core is made of Mn-Zn ferrite or Ni-Zn ferrite. 12. A method for manufacturing a composite magnetic head according to item 11. 14. The method of manufacturing a composite magnetic head according to claim 12 or 13, wherein the intermediate film is an insulating film. 15. The method of manufacturing a composite magnetic head according to claim 14, wherein in the step (i), the insulating film is adhered to the rear magnetic core. 16. The method of manufacturing a composite magnetic head according to claim 12 or 13, wherein the intermediate film is a conductive film. 17. The method for manufacturing a composite magnetic head according to claim 16, wherein in step (i), the conductive film is adhered to the front magnetic core. 18. Claim 12 or 13, characterized in that the intermediate film comprises at least one insulating film and at least one conductive film.
A method for manufacturing a composite magnetic head as described in 2. 19. The composite magnet according to claim 18, wherein in step (i), the insulating film is attached to the rear magnetic core, and the conductive film is attached to the front magnetic core. Head manufacturing method. 20 Claim 1, wherein the insulating film is made of glass or ceramics.
A method for manufacturing a composite magnetic head according to item 4, 15, 18 or 19. 21 The conductor film is Al, Fe, Ni, Co, Cu,
Claims 16 and 17 consist of at least one element selected from the group consisting of Zn, Sn, In, Pb, Ti, Cr, Mo and Si.
A method for manufacturing a composite magnetic head according to item 1, item 18, or item 19. 22 (') Forming an intermediate film made of at least one material selected from the group consisting of insulators and conductors on at least one surface of the front magnetic core body and rear magnetic core body having a predetermined shape to be joined to each other. (') a step of arranging the front magnetic core and the rear magnetic core on the surfaces to be joined in a state of surface contact with each other via the intermediate film, and (') bringing the front magnetic core and the rear magnetic core into contact with each other; The front magnetic core, the rear magnetic core, and the intermediate film are heated to a high temperature within a range that does not soften them, and a voltage is applied between both magnetic cores to join the two magnetic cores, and then the left or right magnetic core is connected. (') repeating steps (') to (') to form the remaining right or left magnetic core blocks, and (') mutually repeating the left and right magnetic core blocks. 1. A method for manufacturing a composite magnetic head, comprising the step of joining via an actuating gap on the surfaces to be joined. 23 In the step ('), ( ₁ ') a predetermined material made of at least one material selected from the group consisting of an insulator and a conductor is applied to at least one surface of the left and right magnetic core blocks to be joined to each other. ( ₂ ') bringing the left and right magnetic core blocks into contact with each other on the surfaces to be joined; and ( ₃ ') forming an intermediate layer with a thickness of 23. The composite magnetic head according to claim 22, further comprising the step of applying a voltage between the left and right magnetic core blocks while heating them to a high temperature at which neither of them softens, thereby joining them together. manufacturing method.