JPH04358045A - Ni-cr-fe soft magnetic alloy - Google Patents

Abstract

PURPOSE:To obtain an inexpensive Ni-Cr-Fe soft magnetic alloy having magnetic properties equal to those of high Ni 'ermalloy' JIS-PC and in which the content of Ni is reduced. CONSTITUTION:In an Ni-Cr-Fe alloy contg., by weight, 30 to 55% Ni and <=14% Cr, the content of S and O as impurities is controlled so as to be <=0.0010% S and <=0.0024% O as well as <=0.0032% (S+O). Furthermore, for obtaining stable magnetic properties, the content of Si is controlled to <=0.30%, Mn to <=0.80%, P to <=0.03% and Al to <=0.30%. By controlling the content of the impurities of S and O and that of Si, Mn, Al or the like required for deoxidation and desulfurization, the growth of crystals is promoted at the time of annealing, and the movement of a magnetic domain wall in the magnetic field is facilitated. As a result, its magnetic properties such as initial permeability ui and maximum permeability un are improved.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention is directed to high Ni permalloy (J
Ni-Cr- with magnetic properties comparable to IS-PC)
This invention relates to a Fe-based soft magnetic alloy.

0002

2. Description of the Related Art Ni--Fe alloys are widely used as case materials for magnetic heads, magnetic shielding members such as magnetic shielding materials for cassette tapes, and iron core materials for various electrical devices. Typical materials belonging to this family include Mo, Cr,
There is a high Ni permalloy (JIS-PC) containing Cu and the like. Although high Ni permalloy exhibits high magnetic permeability and high corrosion resistance, it is expensive because it contains more than 70% by weight of Ni and Mo. Therefore, the use of high Ni permalloy is economically constrained.

[0003] Also, instead of expensive high Ni permalloy,
Low Ni with a relatively low Ni content of about 45% by weight
Permalloy (JIS-PB) is used. Low Ni
Although permalloy has a high saturation magnetic flux density B10 of 15,000 G, its effective magnetic permeability μe is extremely inferior to that of high Ni permalloy. Therefore, high Ni permalloy must still be used for applications requiring high magnetic properties.

[0004] For these reasons, there is a desire to develop a soft magnetic alloy that has magnetic properties comparable to high Ni permalloy, and is low cost or lower than that of low Ni permalloy. In order to meet this demand, the present inventors have developed a soft magnetic alloy with improved saturation magnetic flux density and effective magnetic permeability by containing Ni and Cr in a specified ratio, The patent application was filed as Japanese Patent Application No. 2-78215.

[0005]

[Problems to be Solved by the Invention] In Ni-Cr-Fe alloys, impurities have a greater influence on magnetic properties than in Ni-Fe alloys. In order to prevent the deterioration of magnetic properties caused by these impurities, Japanese Patent Application No. 1-22745 proposes
The content of impurities such as , B, and O was regulated.

[0006] The present invention further develops the improvement of magnetic properties by controlling impurities, and stably achieves a maximum magnetic permeability μm ≧1.
The object of the present invention is to provide a Ni-Cr-Fe based soft magnetic alloy with a weight of 0.00,000.

[0007]

[Means for solving the problems] Ni-Cr-F of the present invention
In order to achieve this purpose, e-based soft magnetic alloys are
In a Ni-Cr-Fe alloy containing 55% by weight of Ni and 14% by weight or less of Cr, S≦0.0010% by weight and O≦0.0024% by weight, and S+O≦0.0
S and O are regulated to 032% by weight, and Si
≦0.30% by weight, Mn≦0.80% by weight, P≦0.0
3% by weight and Al≦0.30% by weight,
It is characterized by regulating Mn, P and Al.

[0008] Ni- containing 35 to 40% by weight of Ni
In Cr-Fe based soft magnetic alloy, 3×(Ni%)
5 to 14 wt% Cr under the condition of -5×(Cr%)≦80
It is preferable to contain. Also, 40 to 52% by weight
In the Ni-Cr-Fe soft magnetic alloy containing Ni, it is preferable to contain 5% by weight or less of Cr under the condition of 50≦(Ni%)+4×(Cr%)≦60.

[0009]

[Function] According to research by the present inventors, Ni-Cr
- Impurities such as S and O contained in the Fe-based soft magnetic alloy are
Together with elements such as Si, Mn, Al, and P, they form sulfides, oxides, etc., and are dispersed in the matrix as nonmetallic inclusions. These nonmetallic inclusions act as an inhibitor when a crystal with a target orientation is grown through heat treatment or the like, and also inhibit the movement of domain walls when a magnetic field is applied to the obtained soft magnetic alloy. As a result, magnetic properties such as maximum magnetic permeability μm and initial magnetic permeability μi are reduced.

In order to eliminate the adverse effects of nonmetallic inclusions, impurity elements such as S and O contained in the alloy and Si,
It is necessary to reduce the content of Mn, Al, etc. as much as possible. However, in the actual melting process, these elements cannot be completely eliminated. The present inventors have determined that the upper limit of the S content, the upper limit of the O content, and the upper limit of the Si, Mn, Al, and P The upper limit of the content was found through numerous experiments.

That is, S≦0.0010% by weight and O
S and O are regulated to be ≦0.0024% by weight and S+O≦0.0032% by weight, Si≦0.30% by weight, Mn≦0.80% by weight, P≦0.03% by weight and A
When regulating l≦0.30% by weight, the maximum magnetic permeability μm
≧100,000, it becomes possible to stably obtain a Ni-Cr-Fe based soft magnetic alloy.

The components and content of the Ni-Cr-Fe based soft magnetic alloy of the present invention will be explained below. Ni: An alloying element necessary to improve magnetic permeability. When the Ni content is less than 35% by weight, the maximum magnetic permeability μm
A high magnetic permeability of 100,000 or more cannot be obtained. In addition, if the Ni content exceeds 55% by weight,
Not only does this increase the cost of the alloy, but it also tends to decrease the saturation magnetic flux density and maximum magnetic permeability. From such a thing,
In the present invention, the Ni content is set in the range of 35 to 55% by weight.

Cr: An important alloying element for improving magnetic permeability, and a Cr content of 14% by weight or less is required. In order to make the maximum magnetic permeability μm 100,000 or more, when Ni is in the range of 35 to 40% by weight, 5 to 14% by weight is required.
of Cr is required, and 3×(Ni
%)-5×(Cr%)≦80. Also,
When Ni is in the range of 40 to 52 wt%, 0.5 to 5 wt% of Cr is required, and 5≦(Ni%) is required between Cr and Ni.
)+4×(Cr%)≦60 is maintained.

[0014] S and O: from the viewpoint of improving magnetic properties,
It is preferable to lower it as much as possible. In particular, since magnetic annealing tends to reduce magnetic permeability, S≦0.001
It is necessary to regulate it to 0% by weight and O≦0.0024% by weight. Further, when satisfying S+O≦0.0032% by weight, the initial magnetic permeability μi is significantly improved as shown in FIG.

Si: An element necessary for deoxidation, but excessive Si content lowers the maximum magnetic permeability μm as shown in FIG. Therefore, the upper limit of the Si content was set to 0.30% by weight.
stipulated.

Mn: An element necessary for deoxidation and desulfurization, but excessive Mn content reduces the maximum magnetic permeability μ as shown in FIG.
m and saturation magnetic flux density B10. Therefore, in the present invention, the upper limit of the Mn content is defined as 0.80% by weight.

Al: An element necessary for deoxidation, but when excessive Al is contained, the maximum magnetic permeability μm and the saturation magnetic flux density B10 decrease as shown in FIG. Therefore, the Al content was set to 0.30% by weight or less.

P: An element mixed in from raw materials, etc. Excessive P content lowers the maximum magnetic permeability μm as shown in FIG. Therefore, in the present invention, the P content is set to 0.03
It was limited to % by weight or less.

[0019] The inventors of the present invention have disclosed the above-mentioned patent application No.
No. 227445 introduces a method of improving the magnetic properties of a Ni-Cr-Fe based soft magnetic alloy by regulating S+O+B to 0.008% by weight or less. B is an element added to improve castability, hot workability, etc., but it has an adverse effect on the magnetic properties of the soft magnetic alloy. Therefore, in Japanese Patent Application No. 1-227445, B≦0
．． 0.005% by weight and S+O+B≦0.008% by weight. However, B is an element that is inherently easy to diffuse, and can be completely removed by selecting annealing conditions during magnetic annealing performed in a hydrogen atmosphere. In this respect, the present invention also has the advantage of relaxing the restrictions regarding B.

[0020]

[Examples] The present invention will be specifically explained below with reference to Examples.

Example 1: An alloy having the composition shown in Table 1 was vacuum melted and cast into an ingot. This ingot was hot rolled and cold rolled to produce a cold rolled plate having a thickness of 0.5 mm. From the obtained cold-rolled sheet, an outer diameter of 45 mm and an inner diameter of 3
A 3 mm circular test piece was cut out. For each specimen, 110
Magnetic annealing was performed by heating in a hydrogen atmosphere at 0° C. for 1 hour.

[0022]

[Table 1]

[0023] When the structure of each test piece was examined after annealing, it was found that
The crystal grain size changed significantly after the (S+O) content reached 0.0032% by weight. That is, for test pieces with (S+O) content exceeding 0.0032% by weight, it is 120 to 1
Comparatively fine crystal grains of 40 μm were formed, whereas comparatively large crystal grains of 200 to 220 μm were formed in the test piece with an (S+O) content of 0.0032% by weight or less.

[0024] Also, the magnetic properties of the test piece were determined according to JIS C2.
531, and the initial magnetic permeability μi and maximum magnetic permeability μm were measured. Then, the initial magnetic permeability μi is (S
When examined in relation to the +O) content, as shown in Figure 1, when (S+O) = 32ppm (0.0032% by weight), the initial magnetic permeability is as high as approximately 20,000 when (S+O)≦32ppm. It was found that it shows μi. It was found that the maximum magnetic permeability μm shows a similar tendency when (S+O)≦32 ppm. Further, in this region, the crystal grain size was as large as 200 to 220 μm.

On the other hand, in the region of (S+O)>32 ppm, the crystal grain size is critically fine to 120 to 140 μm, and the initial magnetic permeability μi also decreases to 10,000 or less. In addition, in addition to test numbers 1 to 7 listed in Table 1, FIG. 1 also lists tests with different S and O contents.

Example 2: An alloy having the basic composition shown in Table 2 was vacuum melted and cast into an ingot. This ingot was hot rolled and cold rolled to produce a cold rolled plate having a thickness of 0.5 mm. An annular test piece having an outer diameter of 45 mm and an inner diameter of 33 mm was cut from the obtained cold-rolled sheet. For each specimen, 11
Magnetic annealing was performed by heating in a hydrogen atmosphere at 00°C for 1 hour.

[0027]

[Table 2]

In the basic composition of Table 2, Si, Mn, A
Materials with various contents of l and phosphorus were prepared, and the influence of the contents of these elements on the magnetic properties was investigated. Note that the magnetic properties were investigated based on JIS C2531. As a result, as shown in Figures 2 to 5, Si = 0.30% by weight
, Mn=0.80% by weight, Al=0.30% by weight and P
A change in magnetic properties was observed at a concentration of 0.03% by weight. That is, Si≦0.30% by weight, Mn≦0.80
wt%, Al≦0.30 wt% and P≦0.03 wt%
Good magnetic properties were obtained with Si>0.
30% by weight, Mn>0.80% by weight, Al>0.30% by weight, or P>0.03% by weight, the magnetic permeability or saturation magnetic flux density decreases.

[0029] It is presumed that the reason why the magnetic permeability changes greatly depending on the element content is mainly due to the influence of nonmetallic inclusions on crystal growth and domain wall movement during annealing. be done. Therefore, by reducing S and O contained in the alloy as much as possible and regulating Si, Mn, Al and P, the influence of non-metallic inclusions can be virtually eliminated, and the maximum magnetic permeability can be as high as 100,000 or more. μ
It has become possible to stably produce a soft magnetic alloy exhibiting m.

[0030]

Effects of the Invention As explained above, the Ni-
In Cr-Fe based soft magnetic alloys, magnetic properties such as initial magnetic permeability μi and maximum magnetic permeability μm are improved by regulating the S and O contents as well as the Si, Mn, Al and P contents. . Since a soft magnetic alloy exhibiting a high maximum magnetic permeability of 100,000 μm or more can be stably obtained with a low Ni content, it is a promising magnetic material as an alternative to the conventional expensive high Ni permalloy.

[Brief explanation of the drawing]

[Figure 1] Graph showing the relationship between (S+O) content and initial magnetic permeability μi

[Figure 2] Graph showing the influence of Si content on magnetic properties

[Figure 3] Graph showing the influence of Mn content on magnetic properties

[Figure 4] Graph showing the influence of Al content on magnetic properties

[Figure 5] Graph showing the influence of P content on magnetic properties

Claims (3)

[Claims] Claim 1: In a Ni-Cr-Fe alloy containing 30 to 55% by weight of Ni and 14% by weight or less of Cr, S≦0.0010% by weight, O≦0.0024% by weight, and S+O≦ S and O are regulated to be 0.0032% by weight, and Si≦0.30% by weight, Mn≦0.
A Ni-Cr-Fe based soft magnetic alloy, characterized in that Si, Mn, P and Al are regulated so that they are 80% by weight, P≦0.03% by weight, and Al≦0.30% by weight. [Claim 2] 3×(Ni%)−5×(Cr%)≦8
35-40 wt.% Ni and 5-14 wt.% under conditions of 0.
In the Ni-Cr-Fe alloy containing Cr, S
S and O are regulated so that ≦0.0010% by weight, O≦0.0024% by weight, and S+O≦0.0032% by weight, and further Si≦0.30% by weight, Mn≦0.80% by weight. , P≦0.03% by weight and Al≦0.30% by weight. [Claim 3] 50≦(Ni%)+4×(Cr%)≦
In the Ni-Cr-Fe alloy containing 40 to 52 wt% Ni and 5 wt% or less Cr under the conditions of
S and O are regulated so that ≦0.0010% by weight, O≦0.0024% by weight, and S+O≦0.0032% by weight, and further Si≦0.30% by weight, Mn≦0.80% by weight. , P≦0.03% by weight and Al≦0.30% by weight.