JP3176385B2 - Method for producing Ni-Fe-Cr soft magnetic alloy sheet - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a soft magnetic alloy suitable for a magnetic shield member and various iron core materials required to have a high magnetic permeability, and is a Ni-alloy having good magnetic properties even in magnetic annealing in a vacuum. The present invention relates to a method for producing an Fe—Cr soft magnetic alloy plate.

[0002]

2. Description of the Related Art Ni-Fe-Cr soft magnetic alloys have excellent magnetic properties close to 80Ni permalloy (JIS-PC) containing Mo, Cu, etc. and are inexpensive, so that magnetic shields are used. It is widely used as a member, for example, a cover material for a magnetic head, a magnetic shielding plate for a cassette tape, and various iron core materials, for example, a yoke for a timepiece and a core material for a small motor. These Ni-Fe-Cr soft magnetic alloys are subjected to a heat treatment called magnetic annealing after processing the final product in order to exhibit high magnetic properties such as high magnetic permeability and low coercive force. The purpose of magnetic annealing is to remove processing strains in the material and to reduce impurity elements such as C and B in the material, which are harmful to the magnetic properties, and to obtain high magnetic properties, and usually in a dry hydrogen gas atmosphere. 900
C. to 1300.degree. C. for about 0.5 to 2 hours. Conventionally, impurity elements such as C and B are reduced in a magnetic annealing step in a dry hydrogen gas atmosphere after processing of a final product. Therefore, no particular study has been made on a method of reducing the impurity elements in a material manufacturing step. When magnetic annealing is performed in a dry hydrogen gas atmosphere, high magnetic properties can be obtained because impurity elements can be reduced. However, when magnetic annealing is performed in a vacuum of 10 ⁻³ torr or more without using hydrogen gas, Cannot remove B, which is an impurity, so that only low magnetic characteristics can be obtained. Therefore, from the viewpoints of safety and economy, there is a strong demand for a method for producing a Ni-Fe-Cr-based soft magnetic alloy sheet exhibiting magnetic properties as high as magnetic annealing in a hydrogen gas atmosphere by magnetic annealing in vacuum even in magnetic annealing. ing.

[0003]

[Knowledge for solving the problem] The inventors have found that Ni-Fe-Cr
As a result of repeated studies on the effects of alloying elements and impurity elements on the magnetic properties of the base soft magnetic alloy sheet, Ni
2 wt%, Cr is 0.5 to 10 wt%, S ≦ 0.003
0 wt%, O ≦ 0.0050 wt%, and S +
For a Ni—Fe—Cr alloy with O ≦ 0.0060 wt%, if the B content mixed as an impurity from the refractory of the furnace wall during melting of this alloy is suppressed to 0.0020 wt% or less, The inventor of the present invention has found that the magnetic properties as high as those in a dry hydrogen gas atmosphere can be obtained by magnetic annealing in a vacuum, and provided the method of Japanese Patent Application No. 2-76600. On the other hand, as a result of continuing investigation on the B content, a hot-rolled material or a cold-rolled material of a Ni—Fe—Cr-based soft magnetic alloy having a B content of 0.030 wt% or less was placed in a dry hydrogen gas or It has been found that the B content can be reduced to 0.0020 wt% or less by performing the short-time finish annealing at 1050 ° C. or more once or more in an atmosphere of a mixed gas of inert gas and inert gas.

[0004]

Configuration of the Invention

Ni: 36 to 52 wt%, Cr: 0.5 to 10 wt%, B: 0.03 wt% or less, S: 0.003 wt% or less, O: 0.005 wt% or less, and the S + O content is 0. a less .006Wt%, the hot-rolled or cold-rolled soft magnetic alloy balance of Fe and unavoidable impurities, before being subjected to the magnetic <br/> gas annealing in vacuum beforehand, Used for normal magnetic annealing
0.002wt in dry substance hydrogen atmosphere of a gas or a mixed gas atmosphere of the dry substance hydrogen gas and an inert gas, by performing one or more times continuously annealed at 1050 ° C. or higher temperatures, the B content that % Or less , Ni
A method for producing a Fe-Cr soft magnetic alloy plate is provided.
According to the present invention, it is possible to provide a Ni—Fe—Cr soft magnetic alloy sheet having good magnetic properties even by magnetic annealing in a vacuum.

[0005]

FIG. 1 shows the alloy Fe-46Ni of the present invention.
110 for -1Cr system and Fe-39Ni-8Cr system
B content and maximum when magnetic annealing at 0 ° C. and soaking for 1 hour was performed in a dry hydrogen gas atmosphere (open white mark) and when performed in a vacuum of 10 ⁻³ torr or more (black null mark). This shows the relationship with the magnetic permeability μm. As is clear from FIG. 1, in the magnetic annealing in a dry hydrogen gas atmosphere, a large change in the maximum magnetic permeability μm due to the B content before the magnetic annealing was not observed. It can be seen that in the magnetic annealing in the middle, when the B content before the magnetic annealing exceeds 0.0020 wt%, the maximum magnetic permeability sharply decreases. Therefore, in order to obtain good magnetic properties by magnetic annealing in a vacuum, it is necessary to make the B content 0.0020 wt% or less. FIG. 2 shows an alloy of the present invention having a B content of 0.025 wt% in a dry hydrogen gas atmosphere (open white mark) and in a mixed gas atmosphere of dry hydrogen gas (50 vol%) and dry nitrogen gas (50 vol%) (black The relationship between the finish annealing temperature and the annealing time, which affects the B content in (Nuri mark), is shown. FIG. 3 shows an alloy of the present invention having a B content of 0.025 wt% in a dry hydrogen gas atmosphere (open white mark) and in a mixed gas atmosphere of dry hydrogen gas (50 vol%) and dry nitrogen gas (50 vol%) ( The influence of the number of times of annealing on the B content after finish annealing for 1 minute in soaking in the range of 900 ° C. to 1100 ° C. is shown. As is clear from FIGS. 2 and 3, the B content is 0.0
3% by weight or less of the alloy of the present invention is annealed in an atmosphere of dry hydrogen gas or an inert gas such as dry hydrogen gas and dry nitrogen gas at a finishing temperature of 1050 ° C. or more for an annealing time of 10 minutes or more, or an annealing time of 1 minute 2 By performing the annealing treatment more than once, the B content can be reduced to 0.0020 wt% or less. Next, the reasons for limiting the composition will be described. Ni is a component that greatly affects the magnetic permeability of the alloy. However, if the Ni content is less than 36 wt%, the maximum magnetic permeability decreases. On the other hand, if the Ni content is too large, the magnetic permeability decreases and the price increases, which is disadvantageous. Therefore Ni
The content is 36 to 52 wt%. Cr is an element that contributes to the improvement of the magnetic permeability and coercive force of the alloy, and its effect requires the content of 0.5 wt% or more. However, if it is too large, the magnetic permeability and the saturation magnetic flux density decrease. . Therefore C
The range of the r content is 0.5 to 10 wt%. S and O greatly affect the magnetic permeability of the alloy and, in order to express sufficient magnetic permeability, the S content is 0.0030 wt% or less, the O content is 0.0050 wt% or less, and the sum of the S + O contents is 0.0060 wt%. % Or less. B can be reduced by annealing in dry hydrogen gas or in a mixed gas atmosphere of dry hydrogen gas and inert gas. However, if the content is too large, the content becomes 0 by short-time annealing such as continuous annealing. In order to reduce the content to 0.0020 wt% or less, the number of times of annealing increases, which is disadvantageous in cost. Therefore, the B content at the time of smelting is set to 0.030 wt% or less. In addition, it is advantageous to use Si or Al as a deoxidizing agent at the time of melting this alloy. It is also advantageous to use Mn as a desulfurizing agent. There is no particular problem with respect to Si and Al used as such a deoxidizing agent and Mn used as a desulfurizing agent as long as their total content is 2% by weight or less. 2w in total content
It also contains t% or less.

Example

[Table 1] 200 kg of Ni-Fe-Cr alloy having the composition shown in Table 1
An ingot is manufactured and subjected to forging, hot rolling, and cold rolling to form a plate having a thickness of 0.6 mm, which is wound into a coil shape, and thereafter, the coil is subjected to finish annealing for dry hydrogen gas or dry hydrogen gas. 100 in a mixed gas atmosphere of
One or more bright continuous finish annealing was performed at a temperature of 0 ° C. to 1100 ° C. for a soaking time of 1 minute. Outer diameter 4 from plate after finish annealing
A ring having a diameter of 5 mm and an inner diameter of 33 mm was cut and subjected to magnetic annealing at 1100 ° C. for 1 hour in dry hydrogen gas or in a vacuum of 10 ⁻⁴ torr, followed by cooling. The maximum permeability μm and coercive force Hc of each of the samples thus obtained were determined according to JISC
The results were shown in Table 2 together with the B content of each sample after finish annealing.

[Table 2] As is evident from Table 2, the Ni-Fe-Cr soft magnetic alloy of the present invention showed high magnetic properties with a maximum magnetic permeability of 100,000 or more in any of the samples by magnetic annealing in dry hydrogen gas. On the other hand, in magnetic annealing in a vacuum, only a sample which has been subjected to finish annealing at 1050 ° C. or more once a minute or more in dry hydrogen gas or a mixed gas atmosphere of dry hydrogen gas and dry nitrogen gas as a pre-process is performed only for one minute. B content is 0.002
Since the content was 0% by weight or less, good characteristics equivalent to magnetic annealing in dry hydrogen gas could be obtained.

[0007]

According to the present invention, Ni-Fe-Cr soft magnetic materials frequently used as a magnetic shield member and various iron core members are harmful to magnetic properties such as magnetic permeability and coercive force.
Can be removed in a short time and simply by adjusting the finish annealing temperature, the soaking time and the atmosphere at the time of finish annealing using a continuous brightening facility or the like. Therefore, since hydrogen gas, which is problematic in safety and economy, is not required at the time of magnetic annealing, it can be manufactured cheaply and safely, and this alloy can greatly contribute to general use of this alloy.

[0008]

[Brief description of the drawings]

FIG. 1 is a graph showing the relationship between the case where the magnetic annealing of the alloy of the present invention is performed in a dry hydrogen gas atmosphere and the case where the magnetic annealing is performed in a vacuum.

FIG. 2 is a graph showing the relationship between the finish annealing temperature and the annealing time on the B content of the alloy of the present invention in dry hydrogen gas and in a mixed gas atmosphere of dry hydrogen gas and dry nitrogen gas.

FIG. 3 is a graph showing the effects of the finish annealing temperature and the number of times of annealing on the B content of the alloy of the present invention after the finish annealing in dry hydrogen gas and in a mixed gas atmosphere of dry hydrogen gas and dry nitrogen gas.

────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Hiroshi Kawai 4976 Nomura Minamicho, Shinnanyo-shi, Yamaguchi Nisshin Steel Co., Ltd. Inside the Steel Research Laboratory (56) References -252756 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) C21D 6/00 C21D 8/12 C21D 9/46 501 C22C 19/00-19/07 C22C 38/00-38 / 60

Claims (1)

(57) [Claims] 1. Ni: 36 to 52 wt%, Cr: 0.5 to 10 wt%, B: 0.03 wt% or less, S: 0.003 wt% or less, O: 0.005 wt% or less, and S + O content is equal to or less than 0.006 wt% of a hot-rolled or cold-rolled soft magnetic alloy balance of Fe and unavoidable impurities, subjected to magnetic <br/> gas annealing in vacuum Before, used in advance for normal magnetic annealing
0.002wt in dry substance hydrogen atmosphere of a gas or a mixed gas atmosphere of the dry substance hydrogen gas and an inert gas, by performing one or more times continuously annealed at 1050 ° C. or higher temperatures, the B content that % Or less , Ni
-A method for producing an Fe-Cr-based soft magnetic alloy plate.