JPH05279826A - Production of 'permalloy(r)' excellent in impedance relative magnetic permeability - Google Patents

Abstract

PURPOSE:To produce a 'Permalloy(R)' excellent in impedance relative magnetic permeability by subjecting a sheet of 'Permalloy(R)' containing specific amounts of Mo or further Cu to magnetic annealing and to rapid cooling under respective ly specified conditions. CONSTITUTION:An ingot of a 'Permalloy(R)' which has a composition consisting of, by weight, 75-85% Ni, 4-6% Mo, and the balance Fe or further containing 4-6% Cu is hot-rolled, or a molten 'Permalloy(R)' is formed into a sheet by a direct continuous casting process. After hot rolled sheet annealing is done at >=900 deg.C, metal oxides are removed from the surface. This 'Permalloy(R)' sheet is cold-rolled once or cold-rolled twice or more while process-annealed between the cold rolling stages and worked to the final sheet thickness. Then, a separation agent at annealing, such as alcohol slurry of alumina, is applied and magnetic annealing is done in a hydrogen-containing atmosphere at >=1000 deg.C. The cooling rate in the range between 600 and 300 deg.C in the latter stage of this annealing is controlled to (100 to 400) deg.C/hr, by which the 'Permalloy(R)' sheet excellent in magnetic properties, particularly in impedance relative magnetic permeability, can be produced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a Ni-Fe alloy, particularly a high Ni-Fe alloy, so-called JIS-PC permalloy. More specifically, the present invention relates to a method for manufacturing permalloy having improved magnetic characteristics and impedance relative permeability.

[0002]

2. Description of the Related Art Ni-Fe magnetic alloys are called permalloys and are used in many fields as soft magnetic materials such as magnetic shields and magnetic heads. The characteristics required for the materials used for these applications are the initial relative permeability at direct current, the maximum relative permeability, or the inductance relative permeability at high frequencies. However, recently, as the use of permalloy expands to zero-phase current transformers, new characteristics are required,
It is a new memory that the impedance relative permeability at commercial frequencies has recently been specified in JIS.

Although many attempts have been made in the past to improve the magnetic characteristics of permalloy, most of them are related to the improvement of direct current relative permeability or inductance relative permeability, and no improvement of impedance relative permeability is found. Absent. As a result of studies by the inventors, the conventional DC relative permeability and the inductance relative permeability in the high frequency range and the commercial frequency impedance relative permeability which is a new required characteristic are not necessarily related to each other, and the conventional characteristic value is the maximum. It was often found that the products manufactured under the conditions described above had a poor impedance relative permeability. Thus, it has been desired to establish a manufacturing method of permalloy that can improve the impedance relative permeability.

[0004]

SUMMARY OF THE INVENTION It is an object of the present invention to provide means for manufacturing permalloy having the best impedance relative permeability.

[0005]

The features of the present invention are as follows.

1)% by weight, Ni: 75% or more, 85%
In the following, Mo: 4% or more and 6% or less, balance: Fe and an alloy consisting of unavoidable impurities are melted and cast into an ingot, which is hot-rolled into a thin plate or a molten alloy is cast directly. To obtain a thin plate by a rapid solidification method, and then to remove the oxide on the surface of the thin plate, and then to obtain the final plate thickness by one or two or more cold rolling steps with intermediate annealing interposed, and thereafter, Applying annealing separator, 1000 ℃
When performing magnetic annealing in the above temperature range, the cooling rate between 600 ° C. and 300 ° C. in the latter stage of the magnetic annealing step is 100 ° C. /
A method for producing permalloy having an excellent impedance relative permeability, which is characterized by controlling at least h and at most 400 ° C./h.

2)% by weight, Ni: 70% or more, 80%
Below, Mo: 3% or more, 5% or less, Cu: 4% or more, 6
%, Balance: Fe and inevitable impurities are melted and cast to form an ingot, which is hot-rolled to form a thin plate, or a molten alloy is cast to directly obtain a thin plate by a rapid solidification method. After making a thin plate, and then removing the oxide on the surface of the thin plate, the final plate thickness is obtained by one or two or more cold rolling steps involving intermediate annealing, and then an annealing separator is applied and the temperature is 1000 ° C or more. When the magnetic annealing is performed at the temperature of, the cooling rate between 600 ° C. and 300 ° C. in the latter stage of the magnetic annealing process is controlled to be 50 ° C./h or more and 400 ° C./h or less. A method for producing permalloy having excellent magnetic permeability. In the present invention, the material can be annealed in a temperature range of 900 ° C. or higher before the oxide on the surface of the thin plate is removed.

The details of the present invention will be described below. The present inventors, conventionally, as a result of reviewing the cooling rate of the material in the magnetic annealing from a viewpoint different from the conventional one, with respect to the point that Permalloy was not necessarily manufactured under the manufacturing conditions that maximize the impedance relative magnetic permeability, By finding the optimum cooling rate, it is possible to obtain a product with extremely excellent impedance relative permeability.

The reasons for limiting the component composition in the present invention will be described. Ni is a basic component of the magnetic alloy of the present invention.
In the case of the Ni-Mo-Fe alloy of the invention, that is, the JIS-PC type 2 alloy, if it is less than 75%, a product having excellent impedance relative permeability cannot be obtained. On the other hand, when the Ni content exceeds 85%, not only the saturation magnetic flux density of the product decreases but also the impedance relative permeability decreases.

In the Ni-Mo-Cu-Fe alloy of the second invention, namely JIS-PC1 type alloy, less than 70% of Ni is contained.
With the content, a product having an excellent impedance relative permeability cannot be obtained. On the other hand, when the Ni content exceeds 80%, not only the saturation magnetic flux density of the product decreases but also the impedance relative permeability decreases.

Mo is an important element that controls the magnetic anisotropy constant and influences the magnetic properties in PC permalloy, and is the Ni-Mo-Fe alloy of the first invention, namely JIS.
-In PC2 type alloy, 4% or more and 6% or less are added. If the Mo content is less than 4%, the desired magnetic properties cannot be exhibited in the product, while if the Mo content is more than 6%, the effect corresponding to the cost increase cannot be obtained.

In the Ni-Mo-Cu-Fe alloy of the second invention, that is, JIS-PC type 1 alloy, 3% or more and 5% or less are added for the same reason as in the first invention.

Cu is related to the magnetic properties through the magnetostriction constant, and is a Ni-Mo-Cu-Fe alloy of the second invention, that is, JIS.
-In PC1 type alloy, 4% or more and 6% or less are added. If the addition amount is out of this range, the magnetic properties of the product will deteriorate. The balance is Fe.

C, S, N, and O are impurity elements, and the smaller the content, the better. Further, it is preferable that there are few inclusions, and a small amount of Si, Al, Mn or the like may be added as a deoxidizing agent for that purpose.

Next, the manufacturing process will be described. Although the melting method is not particularly limited, it is preferable to apply the AOD refining method or the vacuum induction heating melting method in order to reduce impurities and inclusions. The cold-rolled original plate can be produced by a process of casting a molten alloy into an ingot and hot-rolling the ingot to form a hot-rolled plate, or a process of directly obtaining a ribbon by the rapid solidification method of the molten alloy. ..

The hot-rolled sheet or cast ribbon thus obtained is annealed in a temperature range of 900 ° C. or higher, if necessary, and then pickled or mechanically descaled, for example, by jetting sand iron mixed with high-pressure water. The surface oxide removal treatment is performed according to the method used. 1 strip thus obtained
The final plate thickness is obtained by two or more cold rolling steps with intermediate or intermediate annealing.

Next, an annealing separator is applied to the material, and magnetic annealing including a cooling process of heating the material in a temperature range of 1000 ° C. or higher in hydrogen or a hydrogen-containing atmosphere is performed. According to the present invention, in the process of this magnetic annealing step, the temperature from 600 ° C. to 3 ° C.
It is characterized in that the cooling rate between 00 ° C is controlled.

In PC permalloy type 1 and type 2,
For example, in order to maximize the direct current relative permeability, the cooling rate of the material in the magnetic annealing step is 20 ° C. in order to control the degree of ordered lattice transformation and make the magnetic anisotropy constant and magnetostriction constant moderate.
It is considered appropriate to perform slow cooling of about / h. In fact, as will be described in the examples, the maximum DC relative permeability has a maximum value when the material is cooled at a cooling rate of 20 ° C./h. However, under these conditions, the inventors found that the impedance relative permeability, which is the object of the present invention, does not take the maximum value, and that there is an optimum condition at a higher cooling rate unlike the usual concept. Completed the invention.

The component system in the first invention, that is, JIS-P
For C2 type alloys, 100 ° C / h or more, 400 ° C / h
The material is cooled at the following cooling rates. At a cooling rate of less than 100 ° C./h, the impedance relative permeability deteriorates.
On the other hand, in order to cool the material at a cooling rate of over 400 ° C./h, equipment for cooling becomes unsuitable for mass production. Further, in the component system in the second invention, that is, in the JIS-PC type 1 alloy, the material is cooled at a cooling rate of 50 ° C./h or more and 400 ° C./h or less. Impedance relative permeability deteriorates at a cooling rate of less than 50 ° C./h.

The cooling rate of the material in the magnetic annealing for producing the PC permalloy showing the maximum value of the impedance relative permeability at the commercial frequency is the same as the cooling rate for obtaining the product showing the maximum DC maximum relative permeability. Although it is not always clear whether they are different, the present inventors consider that the optimal degree of regularity is related to the magnetization mechanism.

[0021]

【Example】

(Example 1) Ni: 79.8%, Mo: 5.13%, balance Fe and alloy components consisting of unavoidable impurities were melted in a vacuum induction heating melting furnace, cast into a slab, and subjected to breakdown, heat treatment. A hot rolled sheet having a thickness of 5.1 mm was produced by rolling. After removing the surface oxide by surface grinding, it was cold rolled to 0.5 mm, degreased after cold rolling, subjected to intermediate annealing at 900 ° C. for 2 minutes, pickled and cold rolled to 0.1 mm.

JI with outer diameter of 45 mm and inner diameter of 33 mm from a cold rolled sheet
An S-ring test piece was processed, and an alcohol slurry of alumina was applied as an annealing separator, and the S-ring test piece was subjected to 1 in a dry hydrogen atmosphere.
Magnetic annealing was performed at 100 ° C. for 3 hours. At that time 600 ° C
To 300 ° C, cooling rate from 10 ° C / h to 400 ° C
/ H was changed. The results obtained are shown in Table 1.

[0023]

[Table 1]

As shown in Table 1, the maximum DC relative permeability has an optimum point in the vicinity of a cooling rate of 20 ° C./h, but the impedance relative permeability at the commercial frequency has an optimum point for a cooling rate of 100 ° C./h or more. It can be seen that an extremely excellent product having a value of 55,000 or more can be obtained.

(Example 2) Ni: 77.1%, Mo:
An alloy having a composition of 3.92%, Cu: 5.08%, balance Fe and unavoidable impurities is melted in a vacuum induction heating melting furnace, cast into a slab, and broken down and hot rolled to a thickness of 5.1 mm. A hot rolled plate was produced. After removing the surface oxide by surface grinding, cold rolling to 0.5 mm, degreasing after cold rolling, 90
Intermediate annealing was performed at 0 ° C. for 2 minutes, pickling and cold rolling to 0.1 mm.

JI with an outer diameter of 45 mm and an inner diameter of 33 mm from a cold rolled sheet
An S-ring test piece was processed, and an alcohol slurry of alumina was applied as an annealing separator, and the S-ring test piece was subjected to 1 in a dry hydrogen atmosphere.
Magnetic annealing was performed at 100 ° C. for 3 hours. At that time 600 ° C
To 300 ° C, cooling rate from 10 ° C / h to 400 ° C
/ H was changed. The obtained results are shown in Table 2.

[0027]

[Table 2]

As shown in Table 2, the maximum DC relative magnetic permeability has an optimum point in the vicinity of the cooling rate of 20 ° C./h, but the impedance relative magnetic permeability at the commercial frequency has an optimum point in the condition of 50 ° C./h or more. It can be seen that an extremely excellent product having a value of 55,000 or more can be obtained.

[0029]

According to the magnetic annealing method of the present invention, a product having an extremely excellent impedance relative magnetic permeability can be obtained, which is an industrially useful manufacturing method.

[Procedure amendment]

[Submission date] April 30, 1992

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] Claim 2

[Correction method] Change

[Correction content]

[Procedure Amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0007

[Correction method] Change

[Correction content]

2)% by weight, Ni: 70% or more, 80%
Below, Mo: 3% or more, 5% or less, Cu: 4% or more, 6
%, Balance: Fe and inevitable impurities are melted and cast to form an ingot, which is hot-rolled to form a thin plate, or a molten alloy is cast to directly obtain a thin plate by a rapid solidification method. and a thin plate, and then after removal of the oxide of the thin plate surface, to a final thickness by one or intermediate annealing the interposing two or more cold rolling steps, and thereafter, the applied 1000 ° C. or higher annealing separator When the magnetic annealing is performed at the temperature of, the cooling rate between 600 ° C. and 300 ° C. in the latter stage of the magnetic annealing process is controlled to be 50 ° C./h or more and 400 ° C./h or less. A method for producing permalloy having excellent magnetic permeability. In the present invention, the material can be annealed in a temperature range of 900 ° C. or higher before the oxide on the surface of the thin plate is removed.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Toshihiro Shimizu 3434 Shimada, Komitsu-shi, Nippon Steel Co., Ltd.

Claims (3)

[Claims] 1. An alloy consisting of Ni: 75% or more and 85% or less, Mo: 4% or more and 6% or less, balance: Fe and unavoidable impurities in a weight percentage, and cast to form an ingot. Hot-rolled into a thin plate, or a molten alloy is cast to directly obtain a thin plate. A thin plate is obtained by a rapid solidification method, and then oxides on the surface of the thin plate are removed, followed by one or two intermediate annealing. Final plate thickness is obtained by cold rolling process more than once, and after that, an annealing separator is applied and 1000 ℃
When performing magnetic annealing in the above temperature range, the cooling rate between 600 ° C. and 300 ° C. in the latter stage of the magnetic annealing step is 100 ° C. /
A method for producing permalloy having excellent impedance relative permeability, which is characterized by controlling at least h and at most 400 ° C./h. 2. By weight%, Ni: 70% or more and 80% or less, Mo: 3% or more, 5% or less, Cu: 4% or more, 6%
Hereinafter, the balance: an alloy consisting of Fe and unavoidable impurities is melted and cast into an ingot, which is hot rolled into a thin plate, or a molten alloy is cast to directly obtain a thin plate by a rapid solidification method. Then, after removing the oxide on the surface of the thin plate, the final plate thickness is obtained by one or two or more cold rolling steps involving intermediate annealing. When performing magnetic annealing at a temperature, the cooling rate between 600 ° C. and 300 ° C. in the latter stage of the magnetic annealing step is controlled to be 50 ° C./h or more and 400 ° C./h or less, the impedance relative permeability. A method for producing permalloy having excellent magnetic susceptibility. 3. The method for producing permalloy having excellent impedance relative permeability according to claim 1 or 2, wherein the material is annealed in a temperature range of 900 ° C. or higher prior to removing the oxide on the surface of the thin plate.