JP2636609B2 - Non-oriented electrical steel sheet with excellent magnetic properties - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a non-oriented electrical steel sheet having a low iron loss and a high magnetic flux density.

[0002]

2. Description of the Related Art It is important that non-oriented electrical steel sheets used as iron core materials for motors, transformers and the like have low iron loss and high magnetic flux density in order to save energy in electrical equipment. In particular, in recent years, in order to achieve miniaturization and high efficiency of equipment, there is an increasing demand for the development of a material having a higher magnetic flux density than ever before, while keeping iron loss low. Non-oriented electrical steel sheets are classified into grades according to the values of iron loss and magnetic flux density. Generally, high grade materials are S
Although the i content is increased to reduce the iron loss, the magnetic flux density decreases with the increase in the Si content. On the other hand, since the low-grade material has a low Si content, a decrease in the saturation magnetic flux density is suppressed, and although a relatively high magnetic flux density can be obtained, there is a problem that iron loss is high. Therefore, low iron loss and high magnetic flux density cannot be achieved simply by simply adjusting the amount of Si, and appropriate measures must be taken.

[0003] Improvements in the chemical composition, especially S
Some attempts have been made to improve iron loss or magnetic flux density by adding special elements such as b and Sn. For example, regarding Sb addition, JP-A-54-68717,
JP-A-58-147563, JP-A-61-44124
And the addition of Sn is disclosed in
No. 8252, JP-A-56-98420, JP-A-56-98420
No. 102520 has been proposed. In addition, Japanese Unexamined Patent Publication
-180014, JP-A-64-39348, JP-A-2-263952, and the like disclose techniques relating to the composite addition of Sn and Cu, which are described in JP-A-59-157259 and JP-A-63-159259.
No. 33518 and the like describe a technique relating to the combined addition of Sn and Mn, and Japanese Patent Application Laid-Open No.
Each of the techniques relating to the complex addition of n is disclosed.

[0004]

However, among the above proposals, those relating to the addition of Sb do not sufficiently reduce the iron loss because the main purpose is to improve the magnetic flux density, and conversely, those relating to the addition of Sn. However, there is a problem that the improvement of the magnetic flux density (especially the magnetic flux density in a high magnetic field region) is insufficient because the main purpose is to reduce the iron loss. In addition, both technologies Sb,
Long-time hot-rolled sheet annealing or intermediate annealing at two cold pressures to segregate Sn at the grain boundaries, and some technologies require strain relief annealing by the user, thus avoiding complicated processes and cost increases. Absent. In addition, Sn + Cu, Sn + Mn, Mn
In the technology of adding a complex such as + Ni, in order to sufficiently exert the effect, the complex addition amount of these elements is set to 1.0 to 1.0.
It is necessary to be 1.5 wt% or more, and as a result, the saturation magnetic flux density is inevitably reduced. As a result, the improvement of the magnetic flux density itself is not so large.

[0005] As described above, in the prior art, both the iron loss and the magnetic flux density cannot be simultaneously improved sufficiently, or a long-time hot-rolled sheet annealing, a double-cold pressure method, and a strain relief annealing by a user are required. In addition, there is a problem that a complicated process and an increase in cost cannot be avoided.

In response to such a problem, the present applicant firstly
Based on a new finding that the effect of improving magnetic properties can be obtained by adding Ge, a technique capable of avoiding the above-mentioned problems has been proposed as Japanese Patent Application No. 3-84691. That is, Ge
By adding an appropriate amount, the iron loss and the magnetic flux density are sufficient by simply using a normal manufacturing method without complicating the process and increasing the cost due to long-time hot-rolled sheet annealing, double cooling method, etc. Clarified that an improved steel sheet can be obtained.

The present invention is based on the technology for improving the magnetic characteristics by adding Ge, and further advances the technology so that the cost can be further reduced while maintaining the effect of improving the magnetic characteristics by adding Ge. It is intended to provide.

[0008]

Means for Solving the Problems The inventors of the present invention have again examined and considered the advantages and disadvantages of each element added to a steel sheet on the assumption that magnetic properties are improved by adding Ge. as a result,
When Sb and Sn are added alone or in combination with other elements which have been studied in the past, there is a problem in improving the magnetic properties as described above. However, when Sb and Sn coexist with Ge, Does not have such a problem, and can exhibit the same excellent effect of improving magnetic properties as Ge. Therefore, a part of Ge can be replaced with relatively inexpensive Sb and Sn.
As a result, it has been found that a sufficient improvement in magnetic properties equivalent to the case of adding Ge alone can be achieved while reducing the cost.

As will be described in detail later, the gist of the present invention is G
e or Sb or Sn or Sb and Sn in the presence of
However, even with the same composite addition, Sb and Sn
In addition, it was also confirmed that the same effect could not be obtained with the combination of Sb or Sn with other elements such as Cu and Mn in the related art. That is, the effect of improving the magnetic properties obtained by adding Sb and Sn in the coexistence with Ge is based on an effect that is clearly different from that of the prior art. It is clear.

[0010] The present invention has been made based on the above findings, and has at least a structure comprising hot rolling and cold rolling.
And non-directional electromagnetic produced through each process of finish annealing
A steel sheet, C: 0.0050 wt% or less, Si:
0.1 wt% or more and 3.5 wt% or less, Mn: 0.1 wt%
% To 0.9 wt%, P: 0.2 wt% or less, S:
0.015 wt% or less, Al: 1.5 wt% or less, N:
0.0050 wt% or less, Ge: 0.0030 wt% or more and less than 0.0100 wt%, and one or two of Sb and Sn are added to the [Ge] eq. = 0.0100 to 0.1000 where [Ge] eq. =% Ge + (% Sb + % Sn) / 2% Ge: Ge content (wt%)% Sb: Sb content (wt%)% Sn: contained so as to satisfy the Sn content (wt%), the balance Fe and inevitable impurities
This is a non-oriented electrical steel sheet having excellent magnetic properties characterized by being made of a material.

[0011]

Next, the function and effect of the present invention will be described together with the reasons for the limitation. First, the component composition of the steel sheet of the present invention will be described.

(1) Ge amount A group of steel A to a group of steel D shown in Table 1 were melted and made into slabs. Among these steel group A to steel group D, group steel A is composed of Si:
0.14 wt%, Al: tr. , Si + Al ≒ 0.14
wt.% of the following steels containing tr.
(No addition) is added in various ways in the range of 0.0130 wt%. Sb, Sn not added (Steel A-1) Sb: 0.083 wt% addition (Steel A-2) Sn: 0.123 wt% addition (Steel A-3) Sb: 0.056 wt%, Sn: 0.025 wt% Addition (Steel A-4)

The steel B group contains Si: 1.42 wt%, Al:
The following steels containing 0.098 wt% and Si + Al ≒ 1.52 wt% were given a Ge content of tr. (Additive-free)~
It was added with various changes in the range of 0.0130 wt%. Sb, Sn not added (Steel B-1) Sb: 0.026 wt% addition (Steel B-2) Sn: 0.041 wt% addition (Steel B-3) Sb: 0.013 wt%, Sn: 0.030 wt% Addition (Steel B-4)

The steel group C is composed of 1.63 wt% of Si, Al:
The following amounts of steel containing 0.272 wt% and Si + Al ≒ 1.90 wt% were given a Ge content of tr. (Additive-free)~
It was added with various changes in the range of 0.0130 wt%. Sb, Sn not added (Steel C-1) Sb: 0.166 wt% addition (Steel C-2) Sn: 0.098 wt% addition (Steel C-3) Sb: 0.099 wt%, Sn: 0.063 wt% Addition (Steel C-4)

The steel D group is composed of 3.05 wt% of Si, Al:
The following steels containing 0.511 wt% and Si + Al ≒ 3.56 wt% were added with a Ge amount of tr. (Additive-free)~
It was added with various changes in the range of 0.0130 wt%. Sb, Sn not added (Steel D-1) Sb: 0.019 wt% addition (Steel D-2) Sn: 0.032 wt% addition (Steel D-3) Sb: 0.012 wt%, Sn: 0.024 wt% Addition (Steel D-4)

These slabs are subjected to hot rolling-cold rolling-finish annealing or hot rolling-hot rolled sheet annealing-cold rolling-finish annealing under the conditions shown in Table 2 to obtain a sheet thickness of 0.5 mm. A steel sheet was obtained. Thereafter, a ring-shaped test piece was punched from these steel sheets, and their magnetic properties were measured to evaluate the magnetic properties of the steel sheet as an average value in all directions.

FIG. 1 to FIG. 4 show the results arranged in Ge amounts for each of the steel group A to the steel D group. According to these drawings, not only the amount of Si and the amount of Al, but also C, M
In each of the steel group A to the steel group D having different contents of n, P, S and N, that is, regardless of the base component, furthermore, the presence or absence of hot-rolled sheet annealing, and annealing in the case of performing hot-rolled sheet annealing It can be seen that the effect of improving the magnetic properties of Ge can be partially replaced by Sb or Sn regardless of the length of time or the process conditions such as the finish annealing temperature. That is, regarding FIGS. 1 to 4 having different base components and process conditions, the following common results are recognized.

(A) When Sb and Sn are not added and only Ge is added (No. 1 steel of each steel group), Japanese Patent Application No. 3-84
As disclosed in No. 691, Ge: 0.0100 wt%
Above magnetic properties are significantly improved with (magnetic flux density B ₅₀ is increased, the iron loss W _15/50 drops).

(B) When Sb or Sn is added (No. 2 and No. 3 steels in each steel group) or when Sb and Sn are added simultaneously (No. 4 steel in each steel group), Ge:
Even if the content is less than 0.0100 wt%, the same improvement in magnetic properties as in (a) is achieved. However, in this case also Ge
Although the amount has a lower limit, that is, a necessary minimum amount, the lower limit is such that the added amount of Sb and Sn is Sb: 0.012-
0.166 wt%, Sn: 0.024 to 0.123 wt
%, That is, 0.0030 wt%, regardless of the added amount of Sb and Sn.

(C) When Ge is less than 0.0030 wt%, Sb is 0.166 wt% and Sn is 0.123 wt% at the maximum.
Even if it is added by weight% (Steel C-2 and Steel A-3) or Sb and Sn are added by 0.162 wt% as a sum of both (Steel C-4), the improvement in the magnetic properties is as described above ( Much smaller than a).

As described above, even if Ge is not added in an amount of 0.0100 wt% or more, if the amount of Ge added is ensured in an amount of 0.0030 wt% or more, the remainder is added with Sb or Sn or Sb.
It can be seen that the magnetic properties can be remarkably improved as in the case where 0.0100% by weight or more of Ge is solely added. As described above, the gist of the present invention allows a part of Ge to be replaced by relatively inexpensive S while maintaining the remarkable magnetic property improving effect of Ge.
In order to reduce the cost by substituting with b and Sn, the amount of Ge should be at least 0.0030 wt% as described above.
Is necessary, and this is set as the lower limit of the Ge amount of the present invention. On the other hand, if Ge: 0.0100 wt% or more, S
Even if b and Sn are not particularly added, the characteristics are remarkably improved only by adding Ge alone, and in addition, the margin of improvement of the characteristics by adding Sb and Sn is small. Therefore, in the present invention, the Ge amount is set to 0.01.
It was specified as less than 00 wt%.

One of the requirements of the present invention is that the S
b and Sn are added, and the most important requirement is G
e is required to be added. When considering the three of Ge, Sb, and Sn, the combination of multiple additions is a combination containing Ge defined in the present invention, that is, Ge + Sb,
In addition to Ge + Sn and Ge + Sb + Sn, a combination of Sb + Sn is also conceivable. This is No. 1 in each steel group described in Table 1. 4 Ge amount: tr. However, as is apparent from FIGS. 1 to 4, the magnetic properties of this steel are Sb or Sb.
n (Sb or Sn added to the extent corresponding to the amount of Sb + Sn), and there is no great difference.
It is much worse than the steels of the combination n or Ge + Sb.

Specifically, for example, FIG.
The results for 0.14 wt% steel are shown, but Sb:
0.056 wt%, Sn: 0.025 wt%, Sb + S
S containing 0.081 wt% of n and 0 wt% of Ge
b, Sn composite added steel: Ge: 0 wt%, Sb: 0.0
Sb containing 83 wt% (about the same amount as 0.081 wt% which is the Sb + Sn amount of the Sb and Sn composite added steel)
It shows only the same magnetic properties as those of the solely-added steel, and the value of the magnetic properties is Ge: 0.0030 wt% or more, and is remarkably inferior to steel containing Sb or Sn. In addition, the same results were obtained for the steels of FIGS. 2, 3 and 4 having different amounts of Si + Al. This means that the combined addition of Sb and Sn containing no Ge is essentially the same as the case where Sb or Sn is added alone in an amount substantially equal to the combined addition amount, and the two elements are particularly combined. Means no effect. Furthermore, the present inventors also conducted similar studies on steels to which elements such as Cu and Mn shown in the prior art and Sb or Sn were added in combination, and in these combinations,
It was confirmed that the composite addition had no special significance and effect. On the other hand, in the combination of Ge, Sb, and Sn defined in the present invention, the magnetic properties are remarkably improved as described above, and the presence of Ge is indispensable. Only by adding Sn, remarkable improvement in magnetic properties has been achieved. This means that the addition of Sb and Sn in the coexistence with Ge has a distinctly different effect from the composite addition without Ge.

(2) Sb and Sn Amount The gist of the present invention is that a part of Ge is relatively inexpensive Sb and Sn while maintaining an excellent effect of improving magnetic properties by adding Ge.
Is to substitute. In this case, the Sb and Sn amounts naturally have their appropriate ranges.

A group of steels A to D shown in Table 3 were melted to form slabs. Among these Steel Group A to Steel Group D, Steel Group A is:
Si: 0.14 wt%, Al: tr. , Si + Al ≒
0.14 wt%, Ge: 0.0030 to 0.0080 w
It is a steel containing t% and containing Sb and Sn in the following ranges: Sb: tr. ~ 0.2300 wt% (Steel A-5) Sn: tr. (Steel A-6) Sb and Sn were each added at tr. Add within the range of -0.1500 wt% (Steel A-7)

The steel B group contains Si: 1.42 wt%,
Al: 0.098 wt%, Si + Al ≒ 1.52 wt
%, Ge: 0.0030 wt% to 0.0080 wt%, and Sb and Sn are added in the following ranges. Sb: tr. ~ 0.2300 wt% (Steel B-5) Sn: tr. Sb and Sn were added in an amount of tr. Add within the range of ~ 0.1500 wt% (Steel B-7)

The steel group C contains 1.63 wt% of Si and Al:
0.272 wt%, Si + Al ≒ 1.90 wt%, G
e: Steel containing 0.0030 to 0.0080 wt% and Sb and Sn added in the following ranges: Sb: tr. (Steel C-5) Sn added in the range of 0.2 to 0.2300 wt%. Sb and Sn were added in an amount of tr. Add within the range of 0.1500 wt% (Steel C-7)

The steel D group contains: Si: 3.05 wt%, Al:
0.511 wt%, Si + Al ≒ 3.56 wt%, G
e: Steel containing 0.0030 to 0.0080 wt% and Sb and Sn added in the following ranges: Sb: tr. ~ 0.2300 wt% (Steel D-5). Sb and Sn were added in an amount of tr. Add within the range of ~ 0.1500 wt% (Steel D-7)

These slabs were subjected to hot rolling-cold rolling-finish rolling or hot rolling-hot rolled sheet annealing-cold rolling-finish annealing under the conditions shown in Table 4 to obtain a sheet having a thickness of 0.5 mm. A steel plate was obtained. Thereafter, a ring-shaped test piece was punched from these steel sheets, and their magnetic properties were measured to evaluate the magnetic properties of the steel sheet as an average value in all directions. At this time, the present inventors study to formulate a Ge equivalent (hereinafter referred to as [Ge] eq.) On the assumption that Ge is partially replaced by Sb or Sn, which is the gist of the present invention. Was done. As a result, [Ge] eq. =% Ge + (% Sb +% Sn) / 2 where% Ge: Ge content (wt%)% Sb: Sb content (wt%)% Sn: Sn content (wt%) The magnetic properties of this [Ge] eq. , And in addition, this [Ge] eq. It has been found that by controlling the temperature to an appropriate range, the same magnetic properties as those of the previously disclosed single Ge-added steel can be obtained. This means that, when an appropriate amount of Ge coexists, Sb and Sn become [Ge] eq. Has the effect of improving the magnetic properties defined by the [Ge] eq. Need to be defined by Hereinafter, this will be described in detail.

FIGS. 5 to 8 show the magnetic characteristics of the above-mentioned steel group A to steel group D in [Ge] eq. According to these drawings, Ge: 0.0030 to 0.0080 w
Within the range of the present invention of t%, the steels A to which the contents of C, Mn, P, S, and N as well as the amounts of Si and Al are different from each other.
In any of the steel D groups, that is, regardless of the base component, furthermore, regardless of the process conditions such as the presence or absence of hot rolled sheet annealing, the length of the hot rolled sheet annealing, and the finish annealing temperature, etc. Or Sn or both, and adding [Ge] eq. The With 0.0100 wt% or more, increases significantly Ge added alone like the steel flux density B ₅₀ disclosed above, and the iron loss W _15/50 is seen to be reduced dramatically.

Incidentally, as one of the effective means for improving the magnetic properties, there is a hot rolled sheet annealing, but [Ge] e
q. ≒ 0% and [Ge] eq. ≧ 0.0100wt
% In [Ge] eq. The margin of improvement of the magnetic properties by the addition of the hot-rolled sheet annealing at 0% is equal to or higher than that of [Ge] eq. Is 0.01
It is possible to quantitatively understand how much the effect of improving the magnetic properties by setting the content to 00 wt% or more is enormous.

Now, regarding the magnetic flux density, [Ge] e
q. In the region of ≧ 0.0100 wt%, the [Ge] e
q. The dependence is relatively small, from 0.0400 to 0.060
At 0 wt% or more, it gradually decreases. On the other hand, regarding the iron loss, in the range of 0.0100 to 0.1000 wt%, [Ge] eq. Shows a very low value almost independent of the [Ge] eq. Exceeds 0.1000 wt%, the grain growth is inhibited and the iron loss tends to increase significantly.
Therefore, [Ge] eq. In order to improve the magnetic characteristics by appropriate control of [Ge] e, considering the above-mentioned study on the magnetic flux density and the iron loss, especially considering the rise of the iron loss, [Ge] e
q. Must be set to 0.0100 to 0.1000 wt%, which is defined as the range of the present invention.

[Ge] eq. If the value of
As in the case of the steel with single e added, in the component system of Si + Al <1.7 wt%, the hot rolled sheet annealing can be omitted. As is generally known, when magnetic properties are considered, the presence or absence of γ / α transformation is one branch point. In the case of the present invention, [Ge] eq. The effect of optimization is divided, γ / α
In the case of a component system with transformation, that is, in the above example, S
Group A of steels having an i + Al content of less than 1.7 wt% (Si + Al ≒
0.14 wt%) and group B of steel (Si + Al ≒ 1.52)
wt%), [Ge] eq. It can be seen that, if it is within the range of the present invention, even if the rolled sheet is not added with the hot-rolled sheet annealing, the same magnetic flux density and iron loss as the case where the hot-rolled sheet annealing is added can be obtained. On the other hand, in the case of a component system having no γ / α transformation, that is, in the above example, the amount of Si + Al is 1.7 w.
In the steel C group (Si + Al ≒ 1.90 wt%) and the steel D group (Si + Al ≒ 3.56 wt%) of t% or more,
[Ge] eq. The effect of hot-rolled sheet annealing is recognized even in those optimized within the scope of the present invention, and the additional material of the hot-rolled sheet annealing has a higher magnetic flux density than the unrolled hot-rolled sheet annealing omitted material,
Iron loss is lower.

By the way, in the present invention, a very small amount of Ge (0.0030 wt.
% Or more), the remaining amount of Ge added is Sb, Sn
It has been clarified that the effect of improving the magnetic properties equivalent to that of the steel containing only Ge can be obtained even if the addition is carried out, but this is considered to be due to the following reasons.

The magnetic property improving effect of Ge is Sb, Sn
Similarly to the above, this is due to segregation at the crystal grain boundaries to suppress the development of {111} texture, which is undesirable in terms of magnetic properties. However, in the case of Ge, the atomic radius is smaller than that of Sb, Sn, and the like, so that Ge is easily diffused.
As compared with b and Sn, segregation is more rapidly and more segregated at the grain boundaries, and the development of {111} texture is remarkably suppressed.
And, due to such a high Ge diffusion speed,
Long-term hot-rolled sheet annealing and intermediate annealing at two cold pressures, which were indispensable for Sb, Sn, etc., are not particularly required, and only short-time hot-rolled sheet annealing is added, or hot-rolled sheet annealing is added. Even if it is wound without being wound, a sufficient effect of improving magnetic properties can be obtained.

It is considered that the effect of improving the magnetic properties due to Ge is caused not only by the above-mentioned diffusion rate but also by the segregation of Ge at the grain boundaries, thereby lowering the grain boundary interface energy. Can be In order to lower the interface energy to some extent, a predetermined amount of Ge must naturally undergo grain boundary segregation. However, the minimum necessary amount of Ge for this purpose is the lower limit of the Ge amount specified by the present invention. 0030
wt%.

From the above points, in the case of the Ge-added steel disclosed above, in addition to the rapid diffusion of Ge, a small amount of Ge firstly segregates at the grain boundaries, thereby lowering the interface energy upon segregation. As a result, the subsequent segregation of Ge is further accelerated. For this reason, with a small amount of addition compared to Sb, Sn, etc., more rapid and more grain boundary segregation occurs, and
It is considered that the development of the 11｝ texture is significantly suppressed. In addition, in the present invention in which Sb and Sn are added in the coexistence of Ge, by adding 0.0030 wt% or more of Ge, prior to the segregation of Sb and Sn at the grain boundary, first,
Ge, which has a high diffusion rate, segregates at the grain boundaries, which lowers the interfacial energy with respect to segregation, and subsequently accelerates the segregation of Sb and Sn as compared with the steel without Ge. It is considered that the development of {111} texture is suppressed. However, since the diffusion speed of Sb and Sn is lower than that of Ge, the degree of grain boundary segregation is not equal to that of Ge, and [Ge] eq. Ge 1 as seen in
/ 2.

When Ge is contained in an amount of 0.0030 wt% or more, Sb and Sn also have a half effect of Ge in suppressing {111} texture. The present invention relates to [Ge] eq. By defining the amounts of Sb and Sn to be added, the addition of Sb and Sn is made equivalent to the addition of Ge, whereby an effect of improving magnetic properties equivalent to that of steel containing only Ge can be obtained.

On the other hand, in the conventional techniques such as single addition of Sb, Sn, and the like, and combined addition of Sb and Sn, in addition to the slow diffusion speed of these elements, when these elements undergo grain boundary segregation. As described above, since effective lowering of the grain boundary interface energy such as Ge and acceleration of segregation do not occur, as described above, unless these elements are added in a large amount or a long-time segregation treatment is added. , {111} texture cannot be effectively suppressed.

(3) Other components C: an element that deteriorates magnetic properties and also has a detrimental effect on magnetic aging.
An extremely low C of 050 wt% is essential. Si: an element that increases the specific resistance and lowers the iron loss, but it is necessary to add 0.1 wt% or more to obtain this effect. On the other hand, if it exceeds 3.5 wt%, the steel becomes extremely brittle and cracks occur during cold rolling. Therefore, Si is 0.1
To 3.5 wt%.

Mn: 0.1 wt% or more must be added to prevent hot brittleness. On the other hand, when the content exceeds 0.9 wt%, the magnetic flux density deteriorates remarkably. Therefore, Mn is 0.1 to
The range is 0.9 wt%. P: In order to increase hardness and improve punchability,
An appropriate amount can be added. However, if the content exceeds 0.2 wt%, not only these effects are saturated, but also the magnetic properties are rapidly deteriorated, so the upper limit is 0.2 wt%.

S: If it exceeds 0.015 wt%, the grain growth is deteriorated and the iron loss increases. Al: Similar to Si, it is an element that increases specific resistance and lowers iron loss, so that it can be added as necessary up to 1.5 wt%, but if it exceeds this, it becomes extremely brittle and impairs cold rolling properties. The upper limit is 1.5 wt%. N: An element that degrades magnetic properties. To avoid this, it is necessary to set the content to 0.0050 wt% or less. Less than
The balance other than the above elements consists of Fe and unavoidable impurities.
You.

Next, preferred process conditions for obtaining the steel sheet of the present invention will be described. Non-directional electromagnetic of the present invention
The steel sheet is at least hot rolled, cold rolled and finish annealed
The magnetic steel sheet is manufactured through the above steps. By optimizing the component composition as described above, excellent magnetic properties can be obtained regardless of the process conditions. Therefore, there is no particular need to consider the process conditions, and known conditions may be used. However, if known process conditions are applied at random without considering the amounts of Si and Al, for example, there occurs a problem that sufficient grain growth does not occur, and as a result, iron loss deteriorates. Therefore, even when known conditions are applied, there are preferable ranges as described below.

Hot rolling conditions: If the heating temperature of the hot rolling is unnecessarily high, the surface quality is degraded due to scale generation and the yield such as scale loss is reduced. Therefore, the upper limit of the heating temperature is about 1250 ° C. It is desirable to do. Regarding the lower limit, if the heating temperature is extremely low, the rolling temperature during rolling is inevitably lowered, which causes an increase in rolling load.
It is desirable that the lower limit be the degree. The finishing temperature is preferably in the range of about 900 to 700 ° C. in consideration of the heating temperature, the amount of temperature decrease until the finish rolling, and the rolling load.

Regarding the winding temperature, if the hot rolled sheet annealing is not performed as the next step, it is necessary to promote recrystallization of the hot rolled sheet or coarsening of the crystal grains at this stage due to the magnetic properties. It is desirable to set the winding temperature in the following range according to the amount of Si + Al. 0.1 wt% ≦ Si + Al <1.0 wt% ... 630 ° C. or more 1.0 wt% ≦ Si + Al <1.7 wt% ... 670 ° C or more 1.7 wt% ≦ Si + Al <3.0 wt% … 700 ° C or more 3.0 wt% ≦ Si + Al …… 720 ° C or more

On the other hand, when performing hot-rolled sheet annealing, it is sufficient that recrystallization progresses and crystal grains become coarse during hot-rolled sheet annealing.
For this reason, the winding temperature is desirably set to a low temperature of 550 ° C. or less from the viewpoint of preventing an increase in scale and deterioration of surface properties.

Hot rolled sheet annealing conditions: Si + Al <1.7 wt.
%, It is possible to obtain almost the same magnetic properties as in the case where hot-rolled sheet annealing is added as it is wound up without adding hot-rolled sheet annealing, so there is no particular need for hot-rolled sheet annealing. There is no problem in performing hot-rolled sheet annealing in order to improve the coil end property as it is, or to at least slightly improve the magnetic properties.

On the other hand, when Si + Al ≧ 1.7 wt%, the magnetic properties are improved by the addition of hot rolled sheet annealing.
It is desirable to perform hot-rolled sheet annealing as needed. The annealing temperature in the case of performing hot-rolled sheet annealing has a desirable lower limit temperature in order to promote recrystallization of the hot-rolled sheet or to coarsen crystal grains and obtain required magnetic properties. There is a desirable upper limit temperature for preventing the grains from becoming too coarse and deteriorating the surface properties. That is, it is desirable that the annealing temperature be in the following range according to the amount of Si + Al. 0.1 wt% ≦ Si + Al <1.0 wt% ... 700-950 ° C. 1.0 wt% ≦ Si + Al <1.7 wt% ... 725-1000 ° C 1.7 wt% ≦ Si + Al <3.0 wt% ... 750-1050 ° C 3.0 wt% ≦ Si + Al ... 800-1100 ° C The annealing time is desirably 30 seconds or more in order to sufficiently obtain the annealing effect.

Cold rolling conditions: There is no particular limitation, and either normal single rolling or two or more cold rollings with intermediate annealing may be used.

Finish Annealing Conditions: The finish annealing temperature has a desirable lower limit for sufficiently growing crystal grains and obtaining required magnetic properties. On the other hand, the crystal grains become too coarse, and the surface properties are reduced by oxidation. There is a desired temperature as an upper limit to prevent deterioration. That is, it is desirable that the annealing temperature be in the following range according to the amount of Si + Al. 0.1 wt% ≦ Si + Al <1.0 wt% ... 650 to 900 ° C. 1.0 wt% ≦ Si + Al <1.7 wt% ... 700 to 950 ° C. 1.7 wt% ≦ Si + Al <3.0 wt% ... 750 to 1000 ° C 3.0 wt% ≦ Si + Al 850 to 1050 ° C Note that the annealing time is desirably 30 seconds or more in order to sufficiently obtain the annealing effect.

Skin pass rolling conditions: A semi-process material that is subjected to skin pass rolling after finish annealing, punched into a predetermined shape, and then subjected to strain relief annealing. In this case, in order to sufficiently generate grain growth during strain relief annealing, it is desirable that the rolling reduction in the skin pass is 2% or more. On the other hand, if the rolling reduction is excessively large, the crystal grains are rather fine-grained and the magnetic properties deteriorate, so the upper limit is desirably about 12%.

Incidentally, when the skin pass rolling is performed, the crystal grains are coarsened and the iron loss can be reduced, but the magnetic flux density is also lowered at the same time. Semi-process materials of the type that reduce the iron loss to some extent without significantly lowering the magnetic flux density by being subjected to strain relief annealing are also often used. Since the steel sheet of the present invention has both high magnetic flux density and low iron loss at the stage of finish annealing, it is subjected to strain relief annealing after punching as it is, and when the above type of semi-processed material is used, the magnetic flux density is reduced. Iron loss can be further reduced while maintaining a high level, and it becomes possible to provide a semi-process material having more excellent magnetic properties than ever before.

[0053]

【Example】

[Example 1] Steels E to J shown in Tables 5 to 7 were melted and made into slabs, and then hot-rolled, cold-rolled and finish-annealed under the conditions shown in Tables 8 to 10. (No hot rolled sheet annealing) to obtain a steel sheet having a sheet thickness of 0.5 mm. Tables 8 to 10 also show the results of punching ring-shaped test pieces from these steel sheets and measuring the magnetic properties.

As is clear from the table, the contents of C, Mn, P, S and N differ from the contents of Si and Al.
That is, in any of the steel groups E to J having different base components, regardless of the difference in process conditions such as the hot rolling conditions and the finish annealing conditions, the Sb,
Sn, or both of them, and [Ge] eq. Was adjusted to the range of the present invention (N of each steel group)
o. No. 2 steel-No. 4 steel: the steel of the present invention) were all Ge,
Base steel containing no Sb or Sn (No. 1 of each steel group)
Steel) significantly lower magnetic flux density and lower iron loss.

On the other hand, steels having a Ge content below the range of the present invention (No. 5 steel of each steel group: comparative steel) and [Ge] eq. However, the magnetic properties of steels below the range of the present invention (No. 6 steel of each steel group: comparative steels) are not so different from those of the Base steels, and the magnetic flux density and iron loss are significantly inferior to those of the steels of the present invention. Also, [Ge] eq. However, in the case of steel exceeding the range of the present invention (No. 7 steel of each steel group: comparative steel), the magnetic flux density is improved in some cases, but the iron loss is almost the same as or rather increased with the Base steel. Excellent magnetic properties have not been achieved.

[Example 2] Steel group E shown in Tables 5 to 7
The steel J group was subjected to hot rolling, short-time hot-rolled sheet annealing, cold rolling, and finish annealing under the conditions described in Tables 11 to 13 to a sheet thickness of 0.5
mm steel plate was obtained. Tables 11 to 13 also show the results of punching a ring-shaped test piece from these steel sheets and measuring the magnetic properties. According to the same table, Example 1 in the case of as-wound
Similarly, even when a short-time hot-rolled sheet annealing is added, regardless of the components and process conditions, the steel of the present invention has significantly higher magnetic flux density-lower iron loss than Base steel,
It can be seen that the magnetic properties of the comparative steel were not much improved, and were significantly inferior to those of the steel of the present invention.

Example 3 Steel H shown in Tables 6 and 7
Group to Steel J group were subjected to hot rolling, long-time hot-rolled sheet annealing, cold rolling, finish annealing under the conditions described in Tables 14 and 15,
A steel sheet having a thickness of 0.5 mm was obtained. Table 14 shows the results of punching a ring-shaped test piece from these steel sheets and measuring the magnetic properties.
And Table 15 together. According to the table, even when a long-time hot-rolled sheet annealing is added, regardless of the components and process conditions, the steel of the present invention has significantly higher magnetic flux density-lower iron loss than Base steel, and It can be seen that the magnetic properties of the comparative steel are significantly inferior to those of the steel of the present invention.

Example 4 The steels E and F shown in Table 5 were hot-rolled under the conditions shown in Tables 16 and 17.
After subjecting to cold rolling, finish annealing (without hot-rolled sheet annealing), or hot rolling, short-time hot-rolled sheet annealing, cold rolling, and finish annealing, a part is subjected to skin pass rolling and another The part was a steel sheet having a sheet thickness of 0.5 mm without skin pass rolling. A ring-shaped test piece was punched from these steel sheets and
The properties as a semi-process material were evaluated by measuring the magnetic properties after subjected to strain relief annealing at 0 ° C. × 2 hours. The results are shown in Tables 16 and 17.

As is clear from the table, in both the steel E group and the steel F group, that is, regardless of the composition, regardless of the presence or absence of hot-rolled sheet annealing, the presence or absence of skin pass rolling, and other process conditions, The steel of the present invention has remarkably high magnetic flux density and low iron loss as compared with the Base steel and the comparative steel, and the steel of the present invention is either a semi-process material of a type that performs skin pass rolling or a semi-process material of a type that does not perform skin pass rolling. It can be seen that the present invention is also applicable.

[0060]

As described above, according to the present invention, the [Ge] eq. Defined by the component composition, particularly the Ge amount and the Ge, Sb, and Sn amounts. By substituting some of the superior magnetic property improvement effects of Ge with Sb and Sn, the long-time hot-rolled sheet annealing and intermediate annealing at two cold pressures, etc., as in the case of Ge-only steel It is possible to provide a non-oriented electrical steel sheet having a high magnetic flux density and a low iron loss that can be manufactured by a simple process without performing the same.

Such a steel sheet of the present invention can reduce the cost by substituting a part of Ge with inexpensive Sb and Sn, and does not require a complicated process for its manufacture. Therefore, it is possible to reduce the manufacturing cost and shorten the delivery time of the product. Further, the steel sheet of the present invention has a great feature that it has no severe restrictions on process conditions, is easy to manufacture, and can be applied not only to full-process materials but also to semi-process materials, and its application range is wide. As described above, according to the present invention, there is an effect that a full-process material or a semi-process material of a non-oriented electrical steel sheet having excellent magnetic properties can be manufactured at low cost, easily, and with a short delivery time.

[0062]

[Table 1]

[0063]

[Table 2]

[0064]

[Table 3]

[0065]

[Table 4]

[0066]

[Table 5]

[0067]

[Table 6]

[0068]

[Table 7]

[0069]

[Table 8]

[0070]

[Table 9]

[0071]

[Table 10]

[0072]

[Table 11]

[0073]

[Table 12]

[0074]

[Table 13]

[0075]

[Table 14]

[0076]

[Table 15]

[0077]

[Table 16]

[0078]

[Table 17]

[Brief description of the drawings]

FIG. 1 is a drawing showing the influence of the amount of Ge added on the magnetic properties of Si + Al ≒ 0.14 wt% steel (Steel A group).

FIG. 2 is a graph showing the influence of the amount of Ge added on the magnetic properties of Si + Al ≒ 1.52 wt% steel (Steel B group).

FIG. 3 is a drawing showing the effect of the amount of Ge added on the magnetic properties of Si + Al ≒ 1.90 wt% steel (steel C group).

FIG. 4 is a graph showing the influence of the amount of Ge added on the magnetic properties of Si + Al ≒ 3.56 wt% steel (steel D group).

FIG. 5 shows the effect of [Ge] eq. On the magnetic properties of Si + Al ≒ 0.14 wt% steel (Steel A group). Drawing showing the effect of

FIG. 6 shows the effect of [Ge] eq. On the magnetic properties of Si + Al ≒ 1.52 wt% steel (Steel B group). Drawing showing the effect of

FIG. 7 shows the effect of [Ge] eq. On the magnetic properties of Si + Al ≒ 1.90 wt% steel (steel C group). Drawing showing the effect of

FIG. 8 shows the effect of [Ge] eq. On the magnetic properties of Si + Al ≒ 3.56 wt% steel (steel D group). Drawing showing the effect of

 ──────────────────────────────────────────────────続 き Continuation of front page (72) Inventor Akihiko Nishimoto 1-2-1, Marunouchi, Chiyoda-ku, Tokyo Inside Nippon Kokan Co., Ltd. (56) References JP-A-56-133446 (JP, A)

Claims (1)

(57) [Claims] At least hot rolling, cold rolling and finishing
Non-oriented electrical steel sheet manufactured through each step of upper annealing
I, C: 0.0050wt% or less, Si: 0.1wt
% Or more and 3.5 wt% or less, Mn: 0.1 wt% or more and 0.1 wt% or less.
9 wt% or less, P: 0.2 wt% or less, S: 0.015
wt% or less, Al: 1.5 wt% or less, N: 0.005
0 wt% or less, Ge: 0.0030 wt% or more, 0.01
Less than 00 wt%, and containing one or two of Sb and Sn in [Ge] eq. = 0.0100 to 0.1000 [wt%] where [Ge] eq. =% Ge + (% Sb + % Sn) / 2% Ge: Ge content (wt%)% Sb: Sb content (wt%)% Sn: contained so as to satisfy the Sn content (wt%), the balance Fe and inevitable impurities
Non-oriented electrical steel sheet having excellent magnetic properties, characterized in that it consists of things.