JPS59582B2 - Amorphous alloy for magnetic heads with low magnetostriction and high wear resistance and its manufacturing method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an alloy for a magnetic head and a method for manufacturing the same, and particularly the present invention relates to an amorphous alloy for a magnetic head that has CO as a main component and has low magnetostriction and high wear resistance, and a manufacturing method thereof. It is about the method.

Conventionally, MO permalloy metals have been mainly used for magnetic heads, but these alloys have a problem in that when used for long periods of time, the recording characteristics deteriorate significantly due to wear caused by the magnetic tape, especially in video equipment and computer equipment. Since magnetic tape devices for machines and card readers are required to have high reliability, there has been a demand for materials for magnetic heads that have excellent electrical properties and wear resistance.

In addition to the above-mentioned permalloy, high-hardness materials such as ferrite, alperm, and centast are also used as magnetic alloys for magnetic heads.

Of these, ferrite exhibits excellent electromagnetic properties at high frequencies, has high hardness, and has low wear and deformation, but has low saturation magnetization, problems with recording distortion, and high noise, resulting in a signal-to-noise ratio. The inability to increase the S/N ratio is an essential defect.
Furthermore, although Alperm and Centast are excellent in terms of magnetic properties, they have the disadvantage that both hardness and abrasion resistance are not very high. Metal magnetic heads for high-frequency recording generally need to be made into thin plates to prevent deterioration of magnetism due to eddy current loss, but these materials have poor malleability, so it is difficult to make them into thin plates of the required thickness. However, it also has the disadvantage of very poor machinability.

As mentioned above, a magnetic material suitable for high-density recording magnetism has not yet been obtained. Recently, there has been a lot of research into amorphous metal magnetic materials, and in addition to the magnetic properties seen in conventional metal magnetic materials, this material has high electrical resistance, and because it can be obtained essentially in the form of a thin plate due to the manufacturing method, it can be used as a high-frequency magnetic core. It has been reported that it is promising.

That is, Fe, CO, Ni and others P, C, B, Si
Unlike ordinary crystalline magnetic materials, an amorphous metallic magnetic material having a component composition containing about 20 at.
It also has higher electrical resistance and higher hardness than crystalline materials. From this, it appears that amorphous metallic magnetic materials are ideal materials for magnetic head materials. However, as shown in Table 1, when comparing the hardness and wear rate of amorphous, crystalline alloys, and ferrite, conventional amorphous metal magnetic materials have relatively high hardness, but do not have sufficient durability as magnetic heads. Abrasion resistance was insufficient, and improvement in this respect was necessary.
The present invention has low magnetostriction and coercive force, good square hysteresis characteristics, is easy to become amorphous, has high crystallization and magnetic transformation temperatures, is high in hardness, has high wear resistance, and is moldable. The object of the present invention is to provide an amorphous alloy for a magnetic head that is suitable for high-density magnetic recording, and a method for manufacturing the same. The gist of the invention to achieve the above object is that Fe3-7% and Si2.5% in atomic ratio
Hereinafter, an amorphous alloy containing 7 to 30% B and the remainder substantially CO, or an amorphous alloy obtained by replacing a part of CO with the following (A) to (B), respectively, and the production thereof. It is about the method. (a) Ni, Pd, P
The atomic ratio of at least one selected from t is 20% or less.

(b) At least one of P or C in an atomic ratio of 1
Less than 5%.

(c) At least one selected from Cr, V, MO, W, Ti, Zr, and Nb in an atomic ratio of 10% or less.

(d) At least one of Ru and Rh is contained in an atomic ratio of 7% or less.

(e) Mn in atomic ratio of 5% or less.

(f) Cu content in atomic ratio of 5% or less.

(卜) At least two groups selected from the groups (a) to (f) above are present in an atomic ratio of 20% or less.

Next, the present invention will be explained in detail.

The present inventors have previously invented and applied for a patent on a high permeability amorphous amorphous alloy (Japanese Patent Application No. 1510-1982) and a method for modifying the magnetic properties of a high-permeability amorphous alloy (Japanese Patent Application No. 1510-1989).
No. 1509), we conducted various studies to further improve the magnetic properties and wear resistance to make the alloy suitable for magnetic heads.As a result, we developed a molten alloy having the composition of the present invention by ultra-quenching. , by becoming amorphous,
Or by further applying a prescribed heat treatment,
Alternatively, by performing the prescribed heat treatment in a magnetic field, it is possible to impart extremely excellent magnetic properties, and this amorphous alloy has extremely low wear during high-speed contact with a magnetic tape. Magnetic heads using amorphous magnetic materials with this composition exhibit excellent magnetic properties as well as excellent wear resistance, which was not known with conventional amorphous magnetic materials. I newly learned that it is excellent for density recording.

In addition to the above features, the magnetic head alloy of the present invention also has the following features.

Its magnetic properties are hardly degraded by machining. For example, magnetic permeability, coercive force, residual magnetic flux density, etc. remain almost constant even when tension is applied to the alloy, and are insensitive to external stress.
Therefore, the fact that the magnetic properties of the alloy of the present invention hardly deteriorate when subjected to machining such as cutting or punching is very advantageous in manufacturing magnetic heads. Furthermore, another feature of the alloy of the present invention is that the electrical resistance of the alloy is 140 μΩ-? Moreover, since it can be manufactured in the form of a thin plate with a thickness of about 20 to 40 .mu.m, it is an alloy that is very suitable for use in magnetic heads with good high frequency characteristics, that is, magnetic heads for high-density recording. Next, the reason for limiting the composition range of the alloy of the present invention will be described.

When Fe is less than 3% and when it is more than 701), magnetostriction increases and magnetic permeability decreases, making it impossible to obtain sufficient characteristics for magnetic heads, so it is necessary to keep it within the range of 3 to 7%. be.

Sl is an element that helps make the alloy structure amorphous and contributes to increased wear resistance, but if it exceeds 25%, it is difficult to form an amorphous alloy and the alloy becomes brittle.
It is necessary to keep it below 5%.

Note that alloys that do not contain Si can also be used as the amorphous alloy for the magnetic head of the present invention. Like Si, B is an element that helps make the alloy structure amorphous, and when it is less than 7% or more than 30%, it is difficult to form an amorphous alloy and the alloy becomes brittle. 7-30
It must be within the range of %. Note that Si6-25%, B
Within the component range of 8 to 10%, there is even less wear with the magnetic tape, especially Sll 5 to 25% and B 8 to 10%.
Within this range, an amorphous alloy with the best wear resistance, high saturation magnetic flux density, and low coercive force can be obtained.

Nl, Pd, and Pt are all metals belonging to Group 8 and increase magnetic permeability, but if at least one selected from these exceeds 20 (Ff), the saturation magnetic flux density decreases. % or less. P and C help make the alloy structure amorphous, and the higher the amount, the higher the magnetic permeability, but at least one of P and C is 15(f).
1501) since the higher the content, the lower the saturation magnetic flux density.
It is necessary to do the following.

If the content of at least one selected from Cr, V, MO, W, Ti, Zr, and Nb is increased by more than 10%, the hardness and electrical resistance will increase, but the coercive force will also increase, and the magnetic permeability will decrease, resulting in poor high frequency characteristics. It gets significantly worse, so 10(:Ff
) must be as follows. If the amount of at least one of Ru and Rh is more than 7 (fl), the magnetic permeability will increase but the hardness will decrease, so it is necessary to make it 701) or less. M
n is an element that has the effect of increasing electrical resistance and decreasing coercive force, but if it is greater than 5(:F6), the saturation magnetic flux density will be significantly lowered, so it needs to be 5(f) or less.

Cu is an element that does not impair magnetic permeability and coercive force and improves wear resistance, but if it exceeds 5%, the saturation magnetic flux density will drop significantly, so it must be kept at 5% or less.

In the amorphous alloy for a magnetic head according to claim 10 of the present invention, (a), (h), (c), (d), (
At least two selected from the group e) and (f)
If the number of groups is more than 20%, the saturation magnetic flux density will be significantly lowered, so it is necessary to make it 20% or less.

A method for producing an amorphous alloy for magnetic heads according to the present invention will be explained.

By ultra-quenching the molten alloy having the composition of the present invention from the molten state at a cooling rate of at least 104°C/sec to amorphize it, the thin plate-shaped magnetic head of the present invention with low magnetostriction and high wear resistance can be manufactured. Amorphous alloys can be produced.

Since the ultra-quenching cannot be completely amorphized at a cooling rate of less than 104°C/sec, it is necessary to carry out the cooling at a cooling rate of 104°Q/sec or more.

For example, an apparatus as schematically shown in FIG. 1 can be used to ultra-quickly cool the molten state to make it amorphous.

In the figure, reference numeral 1 denotes a quartz tube having a nozzle 2 at its lower end that ejects water in a horizontal direction, into which a raw material alloy 3 is charged and melted. 4 is a heating furnace for heating the raw material alloy 3, and 5 is a heating furnace for heating the raw material alloy 3;
r. p. This is a rotating drum that is rotated at m, in order to minimize the centrifugal force load due to the rotation of the drum.
It is made of a lightweight metal with good heat conductivity, such as an aluminum alloy, and the inner surface is further lined with a metal with good heat conductivity, such as a copper plate 7.

8 is an air piston for supporting the quartz tube 1 and moving it up and down.

The raw material alloy is first charged through the inlet port 1a of the quartz tube 1 by fluid conveyance, etc., and heated and melted in the heating furnace 4. Then, the raw material alloy is heated and melted by the air piston 8 so that the nozzle 2 faces the inner surface of the rotating drum 5. The tube 1 is lowered to the position shown in the figure,
Then, almost at the same time as it starts to rise, gas pressure is applied to the molten alloy 3, and the alloy is jetted toward the inner surface of the rotating drum. In order to prevent the alloy 3 from oxidizing, an inert gas such as argon gas 9 is constantly fed into the quartz tube to create an inert atmosphere. The alloy jetted onto the inner surface of the rotating drum is brought into strong contact with the inner surface of the rotating drum due to the centrifugal force caused by the high-speed rotation, thereby being cooled at an ultra-high speed and can be turned into an amorphous alloy. At least 1
Ultra-quenching at a cooling rate of 0.4 DEG C./second can be carried out by using, for example, a rolling quenching means and apparatus in addition to the centrifugal quenching means and apparatus described above.

In this way, the amorphous alloy of the present invention in the form of a thin ribbon having a thickness of, for example, about 20 μm can be produced.

Ultra-quenching the molten alloy of the present invention has the effect of making it amorphous and eliminating the crystal anisotropy of the alloy.

Furthermore, the amorphous alloy for magnetic heads of the present invention can be obtained by annealing the ultra-quenched amorphous alloy at a temperature below the crystallization temperature of the alloy and then rapidly or slowly cooling it. In this case, it is advantageous for the annealing to be performed in a non-oxidizing atmosphere or in a vacuum. The crystallization temperature of the alloy of the present invention varies depending on its component composition, but is generally within the range of 380 to 550°C, and when annealed at a temperature higher than the crystallization temperature, it recrystallizes and becomes anisotropic. This leads to deterioration of the magnetic properties necessary for use as a magnetic head.

The annealing and the subsequent rapid cooling or slow cooling have the effect of removing processing strain and improving soft magnetism. The alloy of the present invention having excellent properties can be obtained especially when the annealing is carried out at a temperature ranging from 150° C. to below the crystallization temperature.

Note that the retention time in this case is approximately 1 minute to 500 hours. As yet another method for producing the alloy of the present invention, the alloy of the present invention can be obtained by annealing the ultra-quenched and amorphous alloy in a magnetic field and then rapidly or slowly cooling it.

In this case, the conditions for amorphousization by ultra-quenching and the conditions for annealing can be the same as in the other methods of the present invention described above.

In this method, rapid cooling or slow cooling after annealing in a magnetic field has the effect of removing machining strain and aligning the magnetic domain shape in the easy magnetization direction, improving soft magnetism compared to annealing in a non-magnetic field. can. In the method of the present invention, it is usually sufficient for the magnetic field strength to be 5000 e or less, and since magnetization is saturated at 5000 e or more, magnetization cannot be achieved with a stronger magnetic field.

The magnetic properties of the ribbon-like thin plate thus obtained are Gi
Coercive force is 0 when measured with an Offi type B-H loop integrator.
．． 0060e1 An excellent high permeability amorphous alloy with a maximum permeability of 950,000 is obtained.

The ultra-quenching described above has the effect of eliminating crystal anisotropy, and the heating and cooling performed in a non-magnetic field or in a magnetic field after the above-mentioned quenching is for the removal of processing strain, and especially the heating and cooling in a magnetic field has the effect of eliminating crystal anisotropy. It has the effect of aligning the magnetic domain shape in the direction of easy magnetization and improves soft magnetism, and it has been found that this effect is particularly great when heated at a temperature of 150° C. or higher and lower than the crystallization temperature. Next, the relationship between heat treatment and magnetic properties of the alloy of the present invention will be explained.

For example, the Fe-CO-Si-B amorphous alloy of the present invention contains 4.7% of Fe, 5% of Sil, and % of BIO, with the remainder substantially consisting of CO (hereinafter, to simplify the display of the composition of the alloy, Fe4. As a result of measuring coercive force, residual magnetic flux density, and maximum magnetic permeability after various heat treatments using ribbon-shaped samples of 7cO7O.3si, 5BIO),
Characteristic values as shown in Table 2 were obtained.

In particular, sample number 2-4 in the same table is 400℃ in vacuum at 200℃
It is heated in a magnetic field of 0e for 30 minutes and then slowly cooled, and has excellent properties with a coercive force of 0.0060e and a maximum permeability of 950,000 μm, as well as a high hardness of Vickers hardness (H) of 870, making it suitable for magnetic heads. It can be suitably used. Figure 2 shows Fe4.7cO7O. 3Si
FIG. 3 is a diagram showing the results of measuring the hysteresis loop of an alloy having a composition of 15B1O (Alloy No. 1 in Table 3) which was ultra-quenched into a ribbon shape and then wound into a coil.

In the figure, 1 is the case of rapid cooling, 2 is the case of annealing at 200℃ for 120 minutes, and 30 is the case of annealing at 200℃ in a magnetic field of 4000e.
The state of cooling at a rate of 20 C/Hr after heating for minutes is indicated by 3. The coercive force in the rapidly cooled state is 0.0110e1, and the maximum magnetic permeability is 130,000, which can also be used sufficiently for magnetic heads, but when annealed, it becomes 0.0170e1170,000, and it is difficult to use only by annealing. As a result, the squareness increases, and the Vickers hardness, which is an indispensable characteristic for magnetic heads, is 870, and the wear amount (when ferrite is 1) is 3. Conventional products other than ferrite shown in the bottom row of Table 3 It can be seen that it is more suitable for use in magnetic heads because it has less wear compared to the previous one. On the other hand, when the alloy ribbon is annealed in a magnetic field and then rapidly cooled, the coercive force decreases to 0.0060e and the maximum permeability decreases to 950.
,000, the squareness is large, and the Vickers hardness is 8701, and the wear amount is 3 (when ferrite is 1), and it has high magnetic permeability and less wear amount than conventional products. That is, the above-mentioned properties are major features of the amorphous alloy for magnetic heads of the present invention. The influence of tension on the coercive force and residual magnetic flux density of the alloy of the present invention, such as alloy No. 1 in Table 3, which was rapidly cooled was studied, and the results shown in FIG. 3 were obtained.

According to this result, almost no effect of tension was observed;
Another feature of the present invention is that the magnetism of the alloy of the present invention is hardly deteriorated by machining such as cutting or punching. As a result of measuring the high frequency characteristics of the alloy of the present invention, for example alloy number 2-1 in Table 2, the effective magnetic permeability did not change up to a frequency of around 100 KHz, as shown in Fig. 4.
It can be seen that it exhibits excellent properties within the audible frequency range.

The alloy has a resistance of 140μΩ-? as shown in the electrical resistivity column of Alloy No. 1 in Table 3. Since it is easy to manufacture a thin plate of about 20 to 40 .mu.m, the sensitivity of the magnetic head can be improved. On the other hand, in FIG. 4, the effective magnetic permeability of the conventional product (album) is shown by a broken line for comparison, and it can be seen that the product of the present invention far exceeds this characteristic value than the conventional product. As shown in Figures 5 and 6, the wear resistance of the alloy of the present invention is far superior to that of the conventional Centast product, and is almost comparable to that of ferrite.

The measurement shown in Figure 5 has a thickness of 0.07m77! , width 2m
V using an amorphous alloy piece adjusted to m1 length 3 mm
Make a TR magnetic head, set the width of the head track surface in contact with the tape to 0.07 m, the length to 2 mm, and set the relative speed to 1.
1m/SO) CrO2 magnetic tape was rubbed against it to determine the amount of wear. Also, as shown in Figure 6, Fe-CO
-The wear resistance of the Si-B amorphous alloy is such that the wear rate varies between 3 and 5 in the region where it can become amorphous, and the
Although an alloy having an arbitrary wear rate can be obtained by changing the B content, it is clear that an alloy with excellent wear resistance can be obtained in the region surrounded by 8 to 12% B and 5 to 25% Sil. The results of research on the properties of the alloy of the present invention, Alloy No. 1 in Table 3, have been described above, but the trends in these properties are common to all alloys of the present invention.

Next, the present invention will be described with reference to several other embodiments listed in Table 3. Example 1 Table 3 Alloy No. 7 Fe5cO7Osi, 5BlO+W
The results obtained by subjecting the amorphous alloy having the component composition No. 2 to various heat treatments will be explained with reference to Tables 3 and 4.

For example, according to number 3-4 in the same table, 40
After heating in a magnetic field of 00e for 30 minutes, it was slowly cooled. 1 has a maximum magnetic permeability μ771310,000 and a Vickers hardness Hv
86O, and is found to be extremely excellent for use in magnetic heads. Example 2 Table 3 Alloy No. 10 Fe5CO7OSil5BlO+
Tables 3 and 5 explain the results obtained by subjecting an amorphous alloy having a component composition of (Ni+M)2 to various heat treatments.

For example, according to number 4-5 in the same table, 40
The material which was heated for 30 minutes in a magnetic field of 00e and then slowly cooled had a maximum magnetic permeability of μM25O and an OOOl Vickers hardness of Hv85O, which indicates that it is extremely excellent for use in magnetic heads.

Examples 1 and 2 above, and F of alloy number 1 in Table 3
e4.7cO7O. The excellent soft magnetic properties observed in the 3sil5BlO alloy are due to the fact that the amorphous alloy has no crystal anisotropy and has a compositional magnetostriction of 1×1′6 or less.

The magnetic and mechanical properties of the alloys of the present invention having other compositions as well as the alloys of the present invention described above are shown in comparison with conventional products.

As is clear from Table 3, the high magnetic permeability alloy of the present invention has magnetic properties equivalent to or better than conventional products, and has an electrical resistivity that is more than twice that of conventional products, and a significantly higher wear rate. It's going up. It can be seen that although the coercive force of the rapidly cooled amorphous alloy of the present invention is reduced by low-temperature annealing, the magnetic properties can be further improved by annealing in a magnetic field.

In addition, by annealing in a magnetic field, the saturation magnetic flux density of 6800G, 50
Initial permeability of 00, maximum permeability of 950,000 and 0.0
A coercive force of 060e was obtained, but this property was obtained by annealing at a relatively low temperature and has the advantage of not easily deteriorating. Furthermore, in addition to having high electrical resistivity, high hardness, and high wear resistance, it is possible to easily manufacture thin plate samples due to their inherent amorphous properties, and it is also easy to cut and punch. Because it has these great features, it can be very suitably used as a core material for magnetic heads for computers, video recorders, card readers, etc.

[Brief explanation of drawings]

Figure 1 is a schematic diagram showing an example of an apparatus used to ultra-quench the alloy of the present invention from a molten state, and Figure 2 is a
Figure 3 is a diagram showing the hysteresis loop of the Si-B amorphous alloy, Figure 3 is a diagram showing the relationship between coercive force and saturation magnetic flux density with respect to tension in the Fe-CO-Si-B amorphous alloy, and Figure 4 is a diagram showing the relationship between the coercive force and saturation magnetic flux density of the Fe-CO-Si-B amorphous alloy.
- A diagram showing the relationship between frequency and effective magnetic permeability of the CO-Si-B amorphous alloy, FIG. 5 is a diagram showing the relationship between the wear amount and time of the Fe-CO-Si-B amorphous alloy, Figure 6 shows Fe-C
FIG. 3 is a diagram showing the relationship between the amount of wear and composition of an O-Si-B amorphous alloy.

Claims (1)

[Claims] 1. Fe 3 to 7%, Si 25% or less, B7 to atomic ratio
An amorphous alloy for a magnetic head having high magnetic permeability, low magnetostriction, and high wear resistance, comprising 30% and the remainder being substantially Co. 2. The amorphous alloy for a magnetic head having high magnetic permeability, low magnetostriction, and high wear resistance as claimed in claim 1, wherein the atomic ratio is 6 to 25% Si and 8 to 10% B. 3. The amorphous alloy for a magnetic head having high magnetic permeability, low magnetostriction, and high wear resistance as claimed in claim 2, wherein the atomic ratio is 15 to 25% Si. 4 Atomic ratio Fe3~7%, Si25% or less, B7~
An amorphous alloy for a magnetic head having high magnetic permeability, low magnetostriction, and high wear resistance, comprising 30% and 20% or less of at least one selected from Ni, Pd, and Pt, and the remainder being substantially Co. 5 Atomic ratio Fe3~7%, Si25% or less, B7~
At least one selected from 30%, P, and C
An amorphous alloy for a magnetic head, which has high magnetic permeability, low magnetostriction, and high wear resistance, and contains 15% or less of seeds and the remainder is substantially Co. 6 Atomic ratio Fe3~7%, Si25% or less, B7~
30%, 10% or less of at least one selected from Cr, V, Mo, W, Ti, Zr, and Nb, and the remainder substantially consists of Co. High magnetic permeability, low magnetostriction, and high wear resistance. Amorphous alloy for magnetic heads. 7 Atomic ratio Fe3~7%, Si25% or less, B7~
An amorphous alloy for a magnetic head having high magnetic permeability, low magnetostriction, and high wear resistance, comprising 30% or less of at least one selected from Ru, Rh, and 7% or less of any one selected from Ru and Rh, and the remainder being substantially Co. 8 Atomic ratio Fe3~7%, Si25% or less, B7~
An amorphous alloy for a magnetic head having high magnetic permeability, low magnetostriction, and high wear resistance, comprising 30% Mn and 5% or less and the remainder substantially Co. 9 Atomic ratio Fe3~7%, Si25% or less, B7~
An amorphous alloy for a magnetic head having high magnetic permeability, low magnetostriction, and high wear resistance, comprising 30% Cu, 5% or less Cu, and the remainder substantially Co. 10 Atomic ratio Fe3-7%, Si25% or less, B7
~30% and at least two of the following selected from the following groups (a), (b), (c), (d), (e), and (f).
The remainder is substantially C.
An amorphous alloy for magnetic heads that has high magnetic permeability, low magnetostriction, and high wear resistance. (a) At least one selected from Ni, Pd, and Pt in an atomic ratio of 20% or less. (b) At least one of P or C in an atomic ratio of 15
%below. (c) At least one selected from Cr, V, Mo, W, Ti, Zr, and Nb in an atomic ratio of 10% or less. (d) At least one of Ru and Rh is contained in an atomic ratio of 7% or less. (e) Mn in atomic ratio of 5% or less. (f) Cu content is 5% or less in terms of atomic ratio. 11 Atomic ratio Fe3-7%, Si25% or less, B7
~30% and one group selected from the following groups (a) to (g) as necessary, and the remainder substantially consists of Co at a cooling rate of at least 10^4°C/sec. A manufacturing method for an amorphous alloy for magnetic heads that features high magnetic permeability, low magnetostriction, and high wear resistance, characterized by ultra-rapid cooling (
b) At least one selected from Ni, Pd, and Pt in an atomic ratio of 20% or less. (b) At least one of P or C in an atomic ratio of 15
%below. (c) At least one selected from Cr, V, Mo, W, Ti, Zr, and Nb in an atomic ratio of 10% or less. (d) At least one of Ru and Rh is contained in an atomic ratio of 7% or less. (e) Mn in atomic ratio of 5% or less. (f) Cu content is 5% or less in terms of atomic ratio. (G) The atomic ratio of at least two groups selected from the groups (A) to (F) above is 20% or less. 12 Atomic ratio Fe3-7%, Si25% or less, B7
~30% and one group selected from the following groups (a) to (g) if necessary, and the remainder substantially consists of Co at a cooling rate of at least 10^4°C/sec. Production of an amorphous magnetic head alloy with high magnetic permeability, low magnetostriction, and high wear resistance, which is characterized by rapid cooling to make it amorphous, then heating to a temperature below the crystallization temperature of this alloy, and then cooling. Method. (a) At least one selected from Ni, Pd, and Pt in an atomic ratio of 20% or less. (b) The atomic ratio of at least one of P and C is 15% or less. (c) At least one selected from Cr, V, Mo, W, Ti, Zr, and Nb in an atomic ratio of 10% or less. (d) At least one of Ru and Rh is contained in an atomic ratio of 7% or less. (e) Mn in atomic ratio of 5% or less. (f) Cu content is 5% or less in terms of atomic ratio. (G) The atomic ratio of at least two groups selected from the groups (A) to (F) above is 20% or less. 13 Atomic ratio Fe3-7%, Si25% or less, B7
~30% and, if necessary, one group selected from the following groups (a) to (g), and the remainder is substantially Co.
A molten alloy consisting of the following is ultra-quenched at a cooling rate of at least 10^4°C/sec to become amorphous, then heated in a magnetic field to a temperature below the crystallization temperature of the alloy, and then cooled. A method for producing an amorphous alloy for magnetic heads that has high magnetic permeability, low magnetostriction, and high wear resistance. (a) At least one selected from Ni, Pd, and Pt in an atomic ratio of 20% or less. (b) At least one of P or C in an atomic ratio of 15
%below. (c) At least one selected from Cr, V, Mo, W, Ti, Zr, and Nb in an atomic ratio of 10% or less. (d) At least one of Ru and Rh is contained in an atomic ratio of 7% or less. (e) Mn in atomic ratio of 5% or less. (f) Cu content is 5% or less in terms of atomic ratio. (G) The atomic ratio of at least two groups selected from the groups (A) to (F) above is 20% or less. 14. A non-metallic material for a magnetic head having high magnetic permeability, low magnetostriction and high wear resistance as claimed in claim 12 or 13, characterized in that the heating temperature is within a range of 150° C. or higher and lower than the crystallization temperature of the alloy. Method for manufacturing crystalline alloys.