JPS5947017B2 - Magnetic alloy for magnetic recording and playback heads and its manufacturing method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention has 70 to 86% nickel and more than 1% niopium.
% or less, hafnium 0.001 to 5 qb) High permeability magnetic alloy consisting of a small amount of impurities and the balance iron, or as a generated component Nickel 7 0 to 86%, more than 1% niobium and less than 14%, hafnium 0.001 to 5% , molybdenum 8% or less, chromium 7% or less, tungsten 10% as subcomponents.
The following: titanium 7% or less, vanadium 7% or less, manganese 10 or less, germanium 7% or less, zirconium 5% or less, rare earth elements 5% or less, tantalum 10 or less, beryllium 3% or less, boron 1% or less, aluminum 5% or less ,
One or two of silicon 5% or less, tin 5% or less, antimony 5% or less, cobalt 10% or less, and copper 10% or less
This relates to a high permeability magnetic alloy consisting of a total of 0.0.1 to 15% of iron, a small amount of impurities, and the balance iron. There is a magnetic alloy for easy magnetic recording and playback.

Currently, the magnetic material used for audio magnetic recording and playback heads is permalloy, which has high magnetic permeability and is easily molded.
Although Ni-Fe alloys (Ni-Fe alloys) are generally widely used, their hardness is as low as about 110 on the Vickers scale (Qlv), which causes severe wear due to the sliding of magnetic tapes, and it is important to improve this. This has become an issue. Previously, the present inventors published Ni-Fe-
It was disclosed that Nb alloy is a high magnetic permeability alloy with high hardness and excellent wear resistance.

Subsequently, the present inventors added hafnium to the Ni-Fe alloy at the same time as niobium.
As a result of various studies on the alloy, it was discovered that this alloy has high hardness and excellent wear resistance due to the synergistic effect of niobium and hafnium, and is suitable as a magnetic alloy for magnetic heads. Further, M
O. Cr. W. Ti. V. Mn, Ge. Zr) Rare earth element, Ta. Be, B. Al. Si. One or more of Sn, Sb, CO and Cu total 0.01
After conducting research with the addition of ~15% or less, we were finally able to find an alloy that has high magnetic permeability, high hardness, and is easy to forge. That is, the present invention consists of 70 to 86% nickel by weight, more than 1% to 14% niopium, 0.001 to 5% hafnium, a small amount of impurities and the balance iron, or as a main component by weight. Nickel 70-86
%, more than 1% niobium and less than 14%, hafnium 0.00
1 to 5%, as subcomponents molybdenum 8% or less, chromium 7% or less, tungsten 10q17 or less, titanium 7% or less, vanadium 7% or less, manganese 10% or less, germanium 7% or less, zirconium 5% or less, rare earth elements 5
% or less, tantalum 10% or less, beryllium 3% or less, boron 1% or less, aluminum 5% or less, silicon 5% or less, tin 5% or less, antimony 5% or less, cobalt 10% or less, and copper 10% or less. Or two or more types. A total of 0.01 to 15%, a small amount of impurities and the balance iron, the initial magnetic permeability is 3000 or more, the maximum permeability is 5000 or more, and the Vickers hardness is 130 or more. The present invention relates to a high permeability magnetic alloy that can be used for magnetic recording and playback heads, etc., which can be easily heat treated.

Further, a more preferable composition range of the alloy of the present invention is as follows.

That is, the main components are 73 to 84.8% nickel and 1 niobium.
% but less than 10%, hafnium 0.001 to 3%,
Minor components include molybdenum 6% or less, chromium 5% or less, tungsten 7% or less, titanium 5% or less, and vanadium 4C.
$ or less, manganese 7% or less, germanium 5% or less, zirconium 3% or less, rare earth elements 3% or less, tantalum 7
Q6 or less, beryllium 2% or less, boron 0.7% or less, aluminum 3% or less, silicon 3% or less, tin 3% or less, antimony 3% or less, cobalt 7% or less, and copper 7%
More preferred is an alloy consisting of one or more of the following, totaling 0.01 to 10% or less, with a small amount of impurities and the balance iron. The alloy having the above composition is heated at a high temperature above the recrystallization temperature, that is, above 600°C, especially above 800°C and below the melting point, in a non-oxidizing atmosphere or in vacuum for at least 1 minute or more.
After heating for an appropriate time corresponding to the composition at a high temperature to sufficiently remove processing strain and solutionizing to homogenize the structure, it is cooled to a temperature close to the regular-disorder lattice transformation point of approximately 600°C. , hold here for a short time until each part of the structure reaches a uniform temperature, and then increase the temperature to above the above transformation point (V) 100°C
/second to 1℃/hour to room temperature at an appropriate rate corresponding to the composition, or further cooled at a temperature below the ordered-disorder lattice transformation point (about 600℃) for 1 minute to about 100 hours. A magnetic alloy with high magnetic permeability and high hardness can be obtained by heating for an appropriate time depending on the composition and cooling.

From the above solution temperature to the ordered-disorder lattice transformation point (approximately 60
Cooling to a temperature of 0° C.) or higher does not significantly change the magnetism obtained whether the cooling is rapid or slow, but the cooling rate below this transformation point has a large effect on the magnetism.

That is, when cooled from a temperature above this transformation point to room temperature at an appropriate rate corresponding to the composition of 100°C/sec to 1°C/hour, the regularity is generally about 0.1 to 0.6, and the magnetism is excellent. be.
When rapidly cooled at a rate close to 100°C/sec among the above cooling rates, the degree of order decreases to around 0.1; if it is cooled any faster, order does not progress, and the degree of order decreases. b. Magnetism deteriorates. do. However, when an alloy with a low degree of order is reheated to a temperature of 200 to 600 degrees Celsius below its transformation point and cooled, ordering progresses and the degree of order becomes 0.1 to 0.6, which improves the magnetism. On the other hand, from the temperature above the above transformation point, for example 1
If it is slowly cooled at a rate of about 0.degree. C./hour, ordering will proceed too much and the degree of ordering will be about 0.6 or more, resulting in a decrease in magnetism. In short, the composition alloy of the present invention is sufficiently solutionized at a high temperature of 600°C or higher, particularly 800°C or higher and below the melting point,
Excellent magnetism can be obtained by cooling at an appropriate rate and setting the degree of order to an appropriate value in the range of 0.1 to 0.6. If the degree of order is too small due to cooling being too fast, cooling at an additional temperature of 200 to 600°C When reheated at a temperature below the transformation point between the two, the degree of order is adjusted and the magnetism is significantly improved.

Generally, the higher the heat treatment temperature, the shorter the heat treatment time, and the lower the heat treatment temperature, the longer the heat treatment time.

It goes without saying that if the mass of the alloy is large, the heat treatment time may be lengthened, and if the mass is small, the heat treatment time may be shortened. The cooling rate from about 600°C to room temperature to obtain the highest magnetic permeability for each alloy of the present invention varies considerably depending on its composition, but in general, the cooling rate is small and comparable to cooling in a furnace, that is, slow cooling. , which is convenient for application.
For example, when manufacturing a magnetic recording/playback device, heat treatment to remove processing distortion after molding is carried out in a non-oxidizing atmosphere to maintain the shape of the product as much as possible and to avoid the formation of oxides on the surface. Since it is desirable to carry out the process in a medium or vacuum environment, the alloy of the present invention, which exhibits excellent properties when slowly cooled, is well suited for this purpose. Next, the method for manufacturing the alloy of the present invention will be explained in detail in the order of steps.

To make the alloy of the present invention, first the main component is Nickel 70~
86q1), beyond niobium 1 (fl) 1401) and below,
After melting an appropriate amount of 0.001 to 5 (f) of funium and the balance iron in an appropriate melting furnace in air, preferably in a non-oxidizing atmosphere or in vacuum, manganese,
Add a small amount of silicon, aluminum, titanium, boron, calcium alloy, magnesium alloy, and other deoxidizing agents and desulfurizing agents to remove as much impurity as possible, or add molybdenum 8% or less, chromium 7(f) or less, and tungsten to this. 10% or less, titanium 7 (:f) or less, vanadium 7% or less, manganese 10% or less, germanium 7 (F)
f) or less, zircon 5 (11) or less, rare earth elements 5 (f
l) Below, tantalum 10 (f) below, beryllium 301
) below, a total of 0. A fixed amount of 01 to 15(f) is added and thoroughly stirred to produce a compositionally uniform molten alloy.

Next, this is poured into a mold of an appropriate shape and size to obtain a sound ingot, which is then subjected to forming processes such as forging or hot and cold rolling at room temperature or high temperature to form the desired shape. For example, a thin plate with a thickness of 0.3 mm is made. Next, punch out the desired shape and size from the thin plate,
This is heated in hydrogen, other suitable non-oxidizing atmosphere, or vacuum to a temperature above the recrystallization temperature, that is, above about 600°C, particularly above 800°C and below the melting point, for 1 minute to about 100 hours, and then heated according to the composition. For example, 1
Cooling is performed between 00°C/sec and 1°C/hour, in particular between 10°C/sec and 10°C/hour. Depending on the composition of the alloy, this can be further increased to about 600
C. or lower (temperature below the regular lattice-irregular lattice transformation point), particularly 200 to 600.degree. C., for 1 minute or more and about 100 hours or less, and then cooled. Next, examples of the present invention will be described. Example 1 Alloy number 25 (composition Ni=79.5%, Fe=13.1
%, Nb = 7.0%, Hf = 0.4%) alloy raw materials include 99.8% pure electrolytic nickel, 99.9% pure electrolytic iron, 99.8% pure niobium, and 99.8% pure electrolytic iron. %
High purity hafnium was used.

To make a sample, put the total weight of 800' into an alumina crucible,
After melting in vacuum in a high-frequency induction electric furnace, the mixture was thoroughly stirred to obtain a homogeneous molten alloy. Next, add this to a diameter of 25 l.
) The ingot was poured into a mold having holes with a height of 1701 cm, and the resulting ingot was forged at about 1000°C to form a plate with a thickness of about 7 m. Further, it was hot rolled at about 600 to 900°C to a thickness of 1 inch, then cold rolled at room temperature to form a thin plate of 0.1 nm, and then an annular plate with an outer diameter of 44 mm and an inner diameter of 36 mm, and a magnetic head. punched out the core. Next, these were subjected to various heat treatments shown in Table 1, and the annular plate was used to improve magnetic properties and hardness, and the core was used to manufacture a magnetic head, and a Talysurf surface roughness meter was used to measure wear after 300 hours of running with magnetic tape. The amount was measured and the results shown in Table 1 were obtained. Example 2 Alloy number 50 (composition Ni=79.5%, Fe=11.4
%, Nb=6.0%, Hf=0.6%, MO=2.5C
As the alloy raw materials for f)), nickel, iron, niobium, mono-fnium with the same purity as in Example 1 and molybdenum with a purity of 99.501) were used.

The method of manufacturing the sample was the same as in Example 1. The samples were subjected to various heat treatments and the properties shown in Table 2 were obtained. Next, Table 3 shows that after heating in hydrogen at 1250°C for 2 hours,
The properties of representative alloys measured at room temperature are shown by cooling from 00°C to room temperature at various rates, or by further heating at temperatures below 600°C.

Next, the relationship between hafnium, magnetic permeability, hardness and wear amount of the alloy of the present invention will be described in detail with reference to the drawings.

Figure 1 shows 79.5(f)Ni-Fe-7#Nb-Hf
For alloys, the relationship between the amount of mono-funium, hardness, and amount of wear is shown. In general, as the amount of hafnium increases, the hardness increases significantly, and at the same time, the amount of wear decreases significantly, and it can be seen that the effect is particularly large when a small amount of hafnium is added. Figure 2 shows the relationship between the amount of hafnium and the initial magnetic permeability, maximum magnetic permeability, and effective magnetic permeability of the same alloy as in Figure 1. It has the effect of increasing magnetic permeability, and its effect is particularly large in terms of effective magnetic permeability in an alternating current field, which is important for special characteristics of magnetic heads. However, if the hafnium content exceeds 5%, forging and processing become difficult, and the magnetic properties become unsuitable as a magnetic alloy for magnetic heads.
Figure 3 shows 79.5% Ni-Fe-Nb alloy and 79.5% Ni-Fe-0.4% containing 0.4% hafnium.
This figure shows the relationship between the amount of niobium and the hardness of the Hf-Nb alloy, and it can be seen that as the amount of niobium increases, the effect of adding hunium increases significantly. The high hardness of the alloy of the present invention is due to the solid solution hardening of the N1-Fe alloy base due to the effect of niobium, and the fine precipitation of Nb-Hf intermetallic compounds with extremely high hardness in the base due to the addition of hafnium. It is considered that the effect of significantly increasing the hardness is achieved.

In the above experiments, all high-purity metal raw materials were used, but commercially available ferro alloys or various master alloys may also be used for each of these materials.

In this case, the alloy becomes somewhat brittle, so when melting, especially manganese, silicon, aluminum, titanium, boron, etc.
Appropriately use calcium alloys, magnesium alloys, and other deoxidizing and desulfurizing agents to fully deoxidize and desulfurize, giving the alloy good forgeability, hot workability, cold workability, malleability, and free machinability. It is necessary. Magnetic alloys for magnetic heads are required to have an effective magnetic permeability of 3000 or more and a saturation magnetic flux density of 3000G or more at 1 KHz from the viewpoint of magnetic recording and playback sensitivity, but the alloy of the present invention has an effective magnetic permeability of 3000 or more and a saturation magnetic flux density of 3000 G or more at 1 KHz. Since it is 3000G or more, it is suitable as a magnetic alloy for magnetic heads.

In short, the alloy of the present invention is N! An alloy consisting of FeNb and Hf or NOCrWTi999V, Mn
, Ge, Zrl rare earth elements, Ta, Be, B, AlS! One or nine of SnSbCO and Cu
● 99 is a total of two or more types of 0.01 to 1
The alloy with 5% added has very high initial magnetic permeability, maximum magnetic permeability, and effective magnetic permeability, high hardness, and good workability, so it is very suitable as a magnetic alloy especially for magnetic recording and playback snakes. It is also very suitable as a magnetic material for use in electric porcelain.

Next, in the present invention, the composition of the alloy is changed to Nickel 70-86 (
fl), niobium (1#) and 14% or less,...fnium 0.001 to 5 (fl) and the balance iron, and the elements added to this are molybdenum (8#) or less, chromium% or less, tungsten 10 % or less, titanium 7% or less, vanadium 7% or less, manganese 10#) or less, germanium 7 (
f) or less, zirconium 5 (f) or less, rare earth element 5q
1) or less, tantalum 10 (f) or less, beryllium 3 (:
i) The total of one or more of the following: boron 1% or less, aluminum 5% or less, silicon 5(:f) or less, tin 5% or less, antimony 501) or less, cobalt 10% or less, and copper 10% or less The reason for limiting it to 0.01-15% is
As is clear from Table 3 and the drawings, the magnetic permeability and hardness within this composition range are extremely high, and the workability is also good, but when the composition is outside this range, the magnetic permeability and hardness values become low. This is because it is unsuitable as a material for D-magnetic recording and playback devices, which require a lot of force and are difficult to process.

That is, niobium is 1(i) or less and hafnium is 0.0
If the hardness is less than 01#), the hardness will be as low as 130 or less, and the niobium will be less than 1
This is because if the hafnium content exceeds 4% and the hafnium content exceeds 5(f), the hardness is too high, making forging and processing difficult, and the force permeability decreases. In addition to this, the subcomponents are 8% molybdenum, 7% chromium, 10% tungsten, 7% titanium, and 1 vanadium.
0 (f), manganese 10 (fl), germanium 7%,
Rare earth elements 5 (:f), cobalt 10 (I) and copper 1
When added in excess of 0%, the initial permeability increases to 3000.
5% zirconium, 10(f) tantalum, 3(f) beryllium, 1qf boron), 5% aluminum, 5% silicon, 5% tin, and antimony. This is because if each addition exceeds 5%, forging or processing becomes difficult. Furthermore, as is clear from Table 4, Ni-Fe
- When any of the subcomponents is added to a Nb-Hf alloy, the maximum magnetic permeability, the effective magnetic permeability is a large force, the coercive force is a small force,
Since the hardness is large and the wear resistance is improved, the addition of these subcomponents has the same effect in terms of improving magnetic properties and improving hardness and wear resistance, so they are considered to be components with the same effect. It is possible.

If it is desired to improve the corrosion resistance or machinability of the alloy of the present invention depending on the intended use, noble metal elements, lead, phosphorus, tellurium, sulfur, A small amount of calcium may be added.

[Brief explanation of the drawing]

Figure 1 is a characteristic diagram showing the relationship between the hafnium content and hardness and wear amount of a 79.5%Ni-Fe-7%Nb-Hf alloy, and Figure 2 is a characteristic diagram showing the relationship between the hafnium content and the initial magnetic permeability of the same alloy. , is a characteristic diagram showing the relationship between maximum magnetic permeability and effective magnetic permeability at 1 KHz. Figure 3 shows the relationship between maximum magnetic permeability and effective magnetic permeability at 1 KHz. FIG. 2 is a characteristic diagram showing the relationship between the amount of niobium and hardness of an alloy.

Claims (1)

[Claims] 1. A magnetic alloy for magnetic recording and reproducing heads consisting of 70 to 86% nickel, more than 1% niobium and less than 14% niobium, 0.001 to 5% hafnium, a small amount of impurities, and the balance iron. . 2 Consisting of 70-86% nickel, more than 1% niobium and less than 14% niobium, 0.001-5% hafnium, a small amount of impurities and the balance iron in terms of weight ratio, initial magnetic permeability 3000 or more, maximum permeability 5000 or more, and Vickers. The magnetic alloy for magnetic recording and reproducing heads according to claim 1, characterized in that it has a hardness of 130 or more. 3 A composition consisting of 70-86% nickel, more than 1% niobium but less than 14% niobium, 0.001-5% hafnium, a small amount of impurities and the balance iron in a weight ratio is non-oxidized at a temperature of 600°C or more and less than the melting point. After heating in a neutral atmosphere or vacuum for an appropriate time corresponding to the composition for at least 1 minute to 100 hours, it corresponds to the composition from 100℃/sec to 1℃/hour from the temperature above the regular-disorder lattice transformation point. A method for producing a magnetic alloy for magnetic recording and reproducing heads, which comprises cooling to room temperature at an appropriate rate. 4. Non-oxidizing composition consisting of 70-86% nickel, more than 1% niobium but less than 14% niobium, 0.001-5% hafnium, a small amount of impurities and the balance iron at a temperature above 600℃ and below the melting point. After heating in an atmosphere or vacuum for an appropriate time corresponding to the composition for at least 1 minute and up to 100 hours, the temperature is increased from the regular-irregular lattice transformation point to 10
Cool to room temperature at an appropriate rate corresponding to the composition of 0°C/second to 1°C/hour, and then cool for 1 minute or more in a non-oxidizing atmosphere or in vacuum at a temperature below the regular-disorder lattice transformation point. A method for producing a magnetic alloy for magnetic recording and reproducing heads, characterized by heating and cooling for an appropriate time corresponding to the composition within hours. 5 The main components by weight are 70-86% nickel, more than 1% niobium and less than 14%, and 0.001-5% hafnium.
%, as subcomponents molybdenum 8% or less, chromium 7% or less, tungsten 10% or less, titanium 7% or less, vanadium 7% or less, manganese 10% or less, germanium 7% or less, zirconium 5% or less, rare earth elements 5% or less , tantalum 10% or less, beryllium 3% or less, boron 1% or less, aluminum 5% or less, silicon 5% or less, tin 5% or less, antimony 5% or less, cobalt 10% or less, and copper 1
0% or less of one type or two or more types total 0.01-15%
, a magnetic alloy for magnetic recording and playback heads consisting of a small amount of impurities and the balance iron. 6 The main components by weight are 70-86% nickel, more than 1% niobium and less than 14%, and 0.001-5% hafnium.
%, as subcomponents molybdenum 8% or less, chromium 7% or less, tungsten 10% or less, titanium 7% or less, vanadium 7% or less, manganese 10% or less, germanium 7% or less, zirconium 5% or less, rare earth elements 5% or less , tantalum 10% or less, beryllium 3% or less, boron 1% or less, aluminum 5% or less, silicon 5% or less, tin 5% or less, antimony 5% or less, cobalt 10% or less, and copper 1
0% or less of one type or two or more types total 0.01-15%
, consisting of a small amount of impurities and the remainder iron, with an initial magnetic permeability of 3000 or more, a maximum magnetic permeability of 5000 or more, and a Vickers hardness of 13.
6. The magnetic alloy for magnetic recording and reproducing heads according to claim 5, which is patented to have a magnetic recording and reproducing head of 0 or more.