JPS63210237A - Manufacture of non-oriented silicon steel sheet having high magnetic flux density - Google Patents

Abstract

PURPOSE:To obtain a silicon steel sheet excellent in characteristic such as iron loss, magnetic flux density, etc., by hot-rolling a steel stock in which respective contents of C, Si, Mn, P, S and SolAl are specified under specific conditions, by winding the hot-rolled plate at low temp., and by applying descaling, coil rolling, and annealing to the above. CONSTITUTION:The steel stock consisting of <=0.005% C, 0.1-1.0% Si, <=0.20% Mn, 0.050-0.200% P, <=0.005% S, <0.003% SolAl, and the balance Fe with inevitable impurities is hot-rolled by regulating rolling-finishing temp. to a temp. at and above 700 deg.C and within a ferritic range. Successively, the hot-rolled plate is wound up at 600-680 deg.C, descaled, and then subjected to cold rolling and annealing. In this way, a highly homogeneous non-oriented silicon steel sheet reduced in iron loss, improved in magnetic flux density, and having magnetic properties stabilized in the longitudinal direction of the steel strip can be obtained. Further, in order to bring out effectiveness against iron loss and also to eliminate adverse effect of AlN, the additive quantity of SolAl is regulated to 0.150-1.0%.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a method for manufacturing a non-oriented electrical steel sheet with excellent magnetic properties, particularly a high magnetic flux density.

[Conventional technology]

Energy conservation is an important issue regardless of field.

In recent years, in the field of electrical equipment, there has been a call for reducing power consumption, and there has been an increasing demand for improvements in equipment characteristics, miniaturization of equipment, etc.

Non-oriented electrical steel sheets are mainly used as core materials for transformers, ballasts, motors, generators, etc., but in order to meet the demands for improved characteristics and miniaturization of such equipment, it is necessary to A non-oriented electrical steel sheet with a high magnetic flux density is required.

By the way, the so-called -fold cold rolling method is well known as a method for manufacturing non-oriented electrical steel sheets. In this method, a hot rolled steel strip is cold rolled once at a relatively large reduction rate, specifically about 70 to 80%, and then annealed.

However, the conventional one-shot cold rolling method cannot meet the recent high demands.

Regarding iron loss, there are countermeasures to reduce eddy current loss by adding elements that increase specific resistance such as Si or Ap2, but Sl and Ap have the side effect of reducing magnetic flux density, so this kind of Even with these measures, it is impossible to achieve both low iron loss and high magnetic flux density at a high level.

For this reason, various studies have been carried out on non-oriented electrical steel sheets in order to achieve both low iron loss and high magnetic flux density, and various proposals have been made regarding the manufacturing method thereof. For example, in Special Publication No. 57-52410, C0,0
5% or less, total amount of St or Si and Ap, 5% or less, Mn 0.1-1%, 2002% or less A
A method has been proposed in which hot rolling is completed at a temperature between the center temperature of point r and 750°C, and further winding is performed at a temperature of 680°C or higher.
i less than 1.5%, So7! , ApO,0O less than 10%,
Mn0.1-1.0%, less than 9012%, 30.010
A method has been proposed in which a material containing less than 35% NO and OO is hot rolled under the same temperature conditions as the previous proposal.

[Problem that the invention seeks to solve]

In the former method, the temperature is 680°C or higher (preferably 700°C or higher)
It is necessary to wind the material under high temperature conditions.
Furthermore, in order to obtain excellent magnetic properties for the latter, high-temperature winding similar to the above is also required. In these methods, high-temperature winding is required to completely recrystallize the crystal structure of the hot rolled steel sheet and obtain coarse grains.

However, when such high-temperature winding is carried out, a large amount of scale is generated and the descaling performance of the hot-rolled sheet becomes poor.
Decrease in pickling efficiency becomes a problem. In addition, even if the coil is wound at a high temperature, the innermost and outermost parts of the coil are quickly cooled down.
The high temperature holding time is very short at the top and bottom of the coil. As a result, the effect of high-temperature winding cannot be fully expected at the top and bottom parts of the coil, and the magnetic properties of these parts are significantly inferior to those of the middle part, making it impossible to obtain a product with uniform magnetic properties.

In view of the above, the present invention makes it possible to efficiently produce a highly homogeneous non-oriented electrical steel sheet with excellent iron loss and magnetic flux density, and with stable properties over the entire length of the copper strip, without performing high-temperature winding. The purpose is to provide a method that can be used.

[Means for solving problems]

Generally, high-temperature winding causes recrystallization to occur at the stage of hot rolling (hot-rolled sheet) and coarsens crystal grains. This is effective in improving the magnetic properties, as shown in the example of Japanese Patent Publication No. 57-52410 mentioned above, for example.

From this, in general, for non-oriented electrical steel sheets, if recrystallization and grain growth are allowed to occur in the hot-rolled sheet stage, the crystal grains and texture in the finished product after annealing will be affected. , it is thought that improvements in magnetic properties (iron loss, magnetic flux density) will be brought about.

Therefore, the inventors of the present invention conducted various experiments and studies, particularly from the viewpoint of the raw material steel composition, in order to find a countermeasure that can be expected to have the same effect as high-temperature coiling on the crystal structure of hot-rolled sheets. I found out.

○ By restricting S and Mn in the material to below specific amounts, recrystallization and grain growth in the hot-rolled sheet will be accelerated, and recrystallization will proceed sufficiently at the hot-rolled sheet stage even when the sheet is wound at a relatively low temperature. This makes it possible to effectively coarsen the crystal grains.

In this case, the hot rolling finishing temperature must be the ferrite region temperature.

If such a method is adopted, the magnetic properties of the top and bottom parts of the steel strip will be particularly improved compared to when conventional high-temperature winding is applied, and good magnetic properties will be achieved over the entire length of the steel strip. . Moreover, the descaling properties of the hot rolled sheet are improved, and it becomes possible to pickle the hot rolled sheet efficiently.

The present invention is based on the above findings, and is based on CO,00
5% or less, SiO, 1-1.0%, MrO, 20% or less, P0.050-0.200%, s0. o o s%
Below, Sob and All are less than 0.002% or 0.15
A steel material consisting of 0% to 1.0% Fe and unavoidable impurities is hot rolled at a rolling end temperature of 700°C or higher and within the ferrite range, and then heated to 600°C to 680°C.
The gist is a patented manufacturing method characterized by winding at a temperature of °C, followed by descaling, cold rolling, and annealing.

FIG. 1 shows experimental data showing the relationship between the amount of Mn in steel, iron loss, and magnetic flux density under low S conditions.

This is C0. 0 0 3%, 340.5%, Po.
0 8 5%, 30.002%, Soj! ．． ．． Al0
．． ferrite region temperature (8
Hot rolling was carried out with the rolling end temperature set at 20℃) to obtain a plate thickness of 2.

3N, then coiled at 650°C, descaled by pickling, cold rolled to a thickness of 0.5 mm, and then continuously annealed at 750°C for 20 seconds. This is the result of investigating the middle part of the steel strip.

In the figure, it is observed that the magnetic flux density tends to improve as the Mn content in the steel decreases, especially when the MnO content decreases. This tendency is remarkable at 2% or less. This MnO. At 2% or less, the magnetic flux density reaches a level equivalent to that of conventional high-temperature winding material (copper band middle part).

On the other hand, iron loss is MnO. O O 5 ~0. 50%
It shows a constant value in the range of , regardless of the Mn content.

This constant value level is lower than that of a normal once-cold-rolled material, and is comparable to that of a material to which high-temperature coiling is applied (steel strip middle section).

As described above, under low S conditions, the iron loss shows a good level even in the low M range where the Mn content exceeds the range of the present invention (50.2%), but this can be considered as follows.

Under high S conditions, a large amount of MnS etc. precipitates (continuous annealing makes the crystal grains finer and the iron loss is higher). However, when reducing S, Mn
The amount of S precipitated is also reduced and the crystal grain size is large during continuous annealing, and the increase in Mn contributes to an increase in specific resistance, resulting in a good level of iron loss.

However, an increase in Mn tends to decrease the magnetic flux density.

In any case, by reducing S and Mn to satisfy the conditions of the present invention, it is possible to achieve both low iron loss and high magnetic flux density, and at the same time, stabilize the magnetic properties over the entire steel strip.

Incidentally, conventionally, Mn in steel is necessary to suppress hot embrittlement of steel due to S, and Mn inclusions in steel are
It is said to be necessary to coarsen S, improve grain growth during annealing, and reduce iron loss, and it was customary to add at least 0.2%. Regarding hot embrittlement. The present inventors have confirmed that under low S conditions, even if the amount of Mn is reduced, there is no problem in practice.

The method of the present invention will be explained in more detail below.

O First, the reasons for limiting the composition of the steel material used are as follows.

C: From the viewpoint of reducing iron loss, it is better to have less C.

C is 0. If it exceeds 0.05%, the increase in iron loss due to magnetic aging becomes particularly significant. O O 5%
was set as the upper limit. Note that the lower limit is not particularly limited because it is preferable to have less C.

Si: Si is an element that increases specific resistance and effectively contributes to reducing iron loss, but on the other hand, it causes a decrease in magnetic flux density. If it exceeds 1%, the magnetic flux density decreases significantly, making it impossible to achieve the high magnetic flux density that is the object of the present invention. 0 again
．． If it is less than 1%, a sufficient effect in terms of iron loss cannot be expected. Therefore, 0.1-1.

The range was 0%.

Mn: This is the most important element in the present invention. As mentioned above, in the past, it was common to add more than 0.2% from the viewpoint of preventing hot embrittlement caused by S and iron loss, but in the present invention, the amount is reduced to 0.2% or less.

Under low S conditions, if the Mn content is 0.2% or less, as explained in Figure 1 above, the magnetic properties (low iron loss, low iron loss, high magnetic flux density)
will be realized. This is because recrystallization and coarsening of crystal grains in the hot rolled sheet are promoted. In addition, low S
The reason why recrystallization and grain growth are accelerated by lowering Mn is as follows.
Although there are many points that are still unclear, it is thought that the significantly lower amounts of both Mn and 'MnS in solid solution are involved.

Incidentally, when the M intensities exceed 0.2%, the magnetic flux density particularly decreases, as is clear from FIG.

For this reason, in the present invention, the upper limit of Mn is set to 0°2%.
That's what I did.

Note that the lower limit is 1 for Mn/S from the viewpoint of hot embrittlement.
It is desirable that it be 0 or more, but it is not particularly specified.

FDP particularly effectively contributes to improving magnetic flux density.

The effect of P is shown in Figure 2. This data is C01004
%, Si0.4%, Mn0.15%, s0. o.

2%, S o R, AIL 0.200% and P 0.01
The effect on the magnetic properties was examined by changing the temperature between 5% and 0.150%.The sample material was hot rolled at a rolling end temperature of 830℃ (
Ferrite region temperature) to give a plate thickness of 2.1 fl, which was wound at 640°C, and then descaled to a plate thickness of 0.
It was obtained by cold rolling to a temperature of 5 mm and continuous annealing at 780° C. for 10 seconds.

In the figure, the magnetic flux density has a high value in the range where the amount of P is 0.05% or more. There is also a tendency for improvement in iron loss within this range.

Therefore, the lower limit of P was set to 0.050%.

Regarding the upper limit, although it is not necessary from the point of view of magnetic properties,
If the content is too large, embrittlement of the steel plate is unavoidable, and for this reason, the upper limit was set at 0.200%.

S: Forms MnS with Mn, inhibits grain growth during annealing, acts in a direction that inhibits reduction in iron loss, and when present in a large amount causes hot embrittlement. Moreover, it is harmful in promoting recrystallization and grain growth of hot rolled steel sheets. Such adverse effects are particularly significant in low-Mn steels such as those targeted by the present invention, and therefore, it is required that Si be controlled particularly strictly.

From this point of view, S was set to 5% or less of O and OO. This 5O of 1005% or less is a level that is fully possible with current clean steel melting technology.

Note that for S, it is not necessary to specify the upper and lower limits of the characteristic. However, in reality, the scope of implementation is determined by steelmaking technology and economic efficiency.

SoA, Aβ: Like Sl, Aβ is an element that increases specific resistance and contributes to lowering iron loss, but on the other hand, it forms AIN, deteriorates grain growth during annealing, and acts in the direction of increasing iron loss. However, this undesirable effect can be eliminated by increasing the amount of A4N added and making the A4N coarser. In order to bring out the effectiveness against iron loss and eliminate the adverse effects of AnN, it is necessary to add 0°150% or more. But 1
If the addition exceeds %, the magnetic flux density will decrease.

Further, the addition of Aβ is not necessarily required due to the characteristics. If the effectiveness against iron loss is abandoned, one way to remove the negative effects of /IN is to limit AAi to a low level; in this case, the allowable amount should be 0.002% or less. be.

From the above, Sob, Aj! The amount was in the range of 0.15 to 1% or 2% or less of O,OO.

○ Next, we will discuss the manufacturing process.

Material steel having the above-mentioned components is melted in a converter or the like according to a conventional method, and is first subjected to continuous casting or ingot-blowing rolling to form a slab.

This slab is then hot rolled and then rolled up.
Next, it is descaled, cold rolled, and then annealed.

Each process after hot rolling will be explained in detail below.

(2) Hot rolling This step is conditioned on the condition that the rolling end temperature is a ferrite region temperature of 700° C. or higher.

As described above, the present invention is characterized in that magnetic properties are improved by promoting recrystallization and grain growth at the hot-rolled sheet stage. In order to sufficiently promote recrystallization and grain growth in the hot rolled sheet, sufficient strain must be accumulated at the end of hot rolling. From this point of view, in hot rolling, it is necessary to set the rolling end temperature to a temperature within the ferrite range.

From the perspective of recrystallization and grain growth of hot-rolled sheets, it is sufficient to specify an upper limit for the rolling end temperature within the ferrite range, but in reality, if the rolling end temperature falls below 700°C,
The rolling load becomes too large, making it difficult to operate with a normal rolling mill.

From the above, the rolling end temperature was set to be 700°C or higher and within the ferrite range.

(2) Winding The winding temperature must be in the range of 600 to 680'C.

From the standpoint of expecting recrystallization and grain growth of the hot-rolled sheet, it is advantageous to perform high-temperature winding.

Specifically, it is said that winding at a temperature of 680° C. or higher is effective. However, as described above, winding at such a high temperature causes deterioration of descaling performance and variations in characteristic values within a unit coil.

The present invention ensures recrystallization and grain growth of the hot-rolled sheet without performing such high-temperature winding by optimizing the raw material components.

The winding temperature is set at 68°C in order to suppress scale formation, maintain good descaling performance, and reduce property variations.
The temperature should be below 0°C.

However, if the temperature is lower than 600°C, recrystallization and grain growth will not proceed sufficiently, and good magnetic properties cannot be expected.

For the above reasons, the winding temperature was limited to a range of 600 to 680°C.

■ Both descaling and cold rolling can be carried out as usual. Descaling is carried out by pickling. In the case of the present invention, since the descaling properties of the hot rolled sheet are maintained well, pickling can be carried out with high efficiency.

In principle, cold rolling is carried out once, and the reduction rate is usually about 70 to 80%.

(2) Annealing after cold rolling This annealing is carried out for the purpose of recrystallizing the processed structure after cold rolling, as well as adjusting the hardness, and is usually continuous annealing.

Non-oriented electrical steel sheets include full-process products that are shipped with predetermined magnetic properties, and non-oriented electrical steel sheets that are subjected to stress relief annealing (about 750°C x 2 hours) after being processed by the user after shipping, such as punching. There are semi-processed products that have magnetic properties.

Note that even in the case of full-process products, strain relief annealing may naturally be performed on the user's side. Therefore, as full-process products, the specified magnetic Required to demonstrate characteristics.

The present invention is intended for both such full-processed products and semi-processed products, but the annealing after cold rolling is generally 650-b00-860°cx5 for full-processed products.
It is set to be about seconds or more, and the conditions corresponding to this may also be used in the case of the present invention.

Note that when producing electrical steel sheets, there is usually an additional process of applying an insulating coating, but even in the case of the present invention, it is possible to add a coating process as the final process of production, and the present invention shall also include such cases.

〔Example〕

○ Example 1 Steel having the respective compositions shown in Table 1 was melted in a converter, made into a slab by continuous casting, then hot rolled to a thickness of 2.3 m, and made into a coil. I wound it up. The finishing temperature of hot rolling was all in the range of 820 to 850°C. The A r + transformation point of each sample steel was 900° C. or higher, and rolling was completed at a temperature within the ferrite range in all cases. Moreover, the winding temperature was 640 to 660°C.

Next, this hot rolled steel strip was pickled and cold rolled (2.3 m
-0.5m) One continuous annealing was performed. Continuous annealing conditions are the first
As shown in the table.

For each test steel plate thus obtained, eight 30 mm x 280 square Epstein test pieces were taken from the rolling direction of the middle portion of the copper strip and from a direction perpendicular to this, and the magnetic properties were investigated.

The results are shown in the right column of Table 1.

In this example, the manufacturing process was carried out under conditions within the scope of the present invention, and the raw material steel components were changed.

○ Examples 1 to 7 are examples in which the amount of Mn is changed in a steel type with approximately 0.5% Si. Obstacles to surpassing the scope of invention 1~
The magnetic flux density is particularly high compared to floor 3.

○ For steel grades 8 to 12, P is approximately 0.35% Sj.
This is an example in which the amount is changed, and the intervals 10 to 12 of the present invention where Pffi is 0.05% or more are the same as the floors 8. and 8. where Pi is less than that.
In particular, the magnetic flux density is significantly improved compared to 9.

○ Rooms 13 to 17 contain approximately 0.7% S in SiO steel type.
Although the S amount is changed, the present invention's floors 13 to N0.15, which are 30.005% or less, have both iron loss and magnetic flux density compared to lt and 16.17, where the S amount is above that range. It's a good value.

○ Sho 18 to Sumi 22 are approximately 3 in the 0.5% SiO steel type.
on, Aff amount low A7! Table 2 also shows examples of changes within the range (referred to as pickling speed).

However, S o 1. Aj! Examples 18 to 20 of the present invention with less than 0.002% have lower iron loss and higher magnetic flux density than Fish 21.22 where the Sol and All amounts exceed the range.

[Example 2] Steel having each component composition shown in Table 2 was melted in a converter, made into a slab by continuous casting, and then hot rolled to a thickness of 2.1 mm. wound into a coil. The hot rolling end temperature was 800 to 830°C in all cases, and the coiling temperature was as shown in Table 2. All of the sample steels had an Arl transformation point of 90.
The temperature was 0°C or higher, and all hot rolling was completed in the ferrite region.

Next, these hot rolled steel strips were subjected to pickling and cold rolling (2,
1 m1 - 5 n of cold rolling) was subjected to one continuous annealing (Table 2).

Regarding the thus obtained test steel sheet, Epstein test pieces were taken from the top, middle, and bottom parts of the coil during hot rolling in the same manner as in Example 1, and the magnetic properties were investigated. The results of this investigation and the highest pickling line speed that allows complete descaling during pickling (hereinafter simply ○) are steel composition conditions that are within the range of the present invention. l!11.2 is The winding temperature is lower than the range of the present invention, and both iron loss and magnetic flux density are inferior.Also, the winding temperature of Sake 6 is higher than the range of the present invention, and the magnetic properties are good. However, the descaling performance during pickling has deteriorated and the pickling speed has decreased.

On the other hand, positives 3 to 5 whose winding temperature is within the range of the present invention are as follows:
Both magnetic properties and pickling speed have reached a high level.

○ 11kL7.8 has Mn and S outside the conditions of the present invention in terms of steel composition, and although the coiling temperature of No. 7 is within the range of the present invention, good magnetic properties were not obtained. Not yet. In addition, in case No. 8, the winding temperature is above the range of the present invention, and good magnetic properties are obtained in the middle part of the copper strip, but the magnetic properties are poor in the top and bottom parts, and the longitudinal part of the copper strip has good magnetic properties. Characteristic variations in the directions are large. Moreover, the pickling speed is also low.

[Example 3] Example 1.2 shows the results of magnetic measurements taken after cutting the Epstein test piece. The Epstein test pieces taken from the samples were further subjected to strain relief annealing at 750 x 2 h, and then their magnetic properties were evaluated. This simulates the case where strain relief annealing is applied to a full process product.

The results are shown in Table 3.

Examples 5.12.13.19 of Table 3 are examples of the present invention, and these exhibited good magnetic properties of low iron loss and high magnetic flux density even after strain relief annealing.

〔Effect of the invention〕

As is clear from the above explanation, according to the method of the present invention,
It is possible to produce a highly homogeneous non-oriented electrical steel sheet with low iron loss, high magnetic flux density, and stable magnetic properties in the longitudinal direction of the copper strip.Moreover, since high aL winding is not performed, it is possible to produce a hot-rolled sheet. The descaling property of the descaling process is maintained well, and pickling as a descaling process can be carried out with high efficiency.

Therefore, the present invention greatly contributes to improving the performance and manufacturing efficiency of non-oriented electrical steel sheets.

[Brief explanation of the drawing]

FIG. 1 is a plot diagram showing the relationship between M n 177 and magnetic properties under low S conditions, and FIG. 2 is a plot diagram showing the effect of P on magnetic properties. Figure 1 Figure 2 0.050 0.100 0.150
April 8, 1985 Director General of the Patent Office Black 1) Ming 2# Patent Application No. 43534 of 1988 2 Title of Invention Method for manufacturing non-oriented electrical steel sheet with high magnetic flux density 3. Relationship with the case of the person making the amendment Patent applicant address: 5-15 Kitahama, Higashi-ku, Osaka Name (211) Yasuo Shingu, Representative of Sumitomo Metal Industries Co., Ltd. Address of agent: 5-44 Kawaramachi, Higashi-ku, Osaka ( Daika Building) Showa year, month, day (Date of document shipment: Showa year, month, day) /□-6, "Claims" column and "Detailed description of the invention" column 7 of the specification subject to amendment, Contents (1) The scope of claims in the specification will be amended as shown in the attached sheet. (2) Correct the statement rMr0.20J on the last line of page 6 of the specification to rMn0.20J. (Attachment) Claims ft) c0.005% or less, Si0.1-1.0%
, y and 0.20% or less, P0.050 to 0.200%,
S0.005% or less, S o 12. Ai! 0.00
A steel material consisting of Fe and unavoidable impurities with a balance of less than 2% is hot rolled at a rolling end temperature of 700°C or higher and within the ferrite range, then coiled at a temperature of 600 to 680°C, and then A method for manufacturing a non-oriented electrical steel sheet with high magnetic flux density, which comprises performing descaling, cold rolling, and annealing. (2) C0,005% or less, Si0.1-1.0%
, Mn 0.20% or less, P 0.05-0.200%, s
0. o. 5% or less, Sob, . A steel material consisting of 0.150 to 1.0% Al and the remainder Fe and unavoidable impurities is hot rolled at a rolling end temperature of 700°C or higher and within the ferrite range, and then heated at 600 to 680°C. A method for manufacturing a non-directional electromagnetic m-plate with high magnetic flux density, which comprises winding at high temperature, followed by descaling, cold rolling, and annealing. Procedural Amendment (June 80, 1988 Patent Application No. 43534 2, Title of Invention Method for Manufacturing Non-oriented Electrical Steel Sheet with High Magnetic Flux Density 3, Relationship with the Person Making the Amendment Case Patent Application Person Address: 5-15 Kitahama, Higashi-ku, Osaka Name (211) Sumitomo Metal Industries Co., Ltd. Representative: Yasuo Shingu 4 Agent address: 5-44 Kawaramachi, Higashi-ku, Osaka (Daika Building) Showa Year, month, day, positive 9 , especially magnetic flux density 6 for column 10, "Detailed Description of the Invention" column 7 of the specification subject to amendment, contents of amendment (1) 1820 from line 4 to line 5 on page 18 of the specification.
~850'CJ was corrected to 1750-810°C, and on line 6 of the same page, ``900°C'' was corrected to 850°C. (2) Table 1 of Section 19 of the Specification will be amended as shown in the attached sheet. (3) Page 20 of the specification, line 4 “○ Floor 1-South 7...
'' to page 21, line 4, ``...high magnetic flux density.'' has been corrected as below. [ON0.1 to floor 8 is M in steel type with approximately 0.5% Si.
This is an example in which the n amount is changed, and inventive example No. 0.2 in which the Mn amount is 0.2% or less. The magnetic flux densities of teeth 4 to 8 are higher than those of floors 1 to 3, where the Mn content is above the range of the present invention. Om9 to Minami 13 are Pg in steel types with approximately 0.35% Si.
In the examples No. 0.11 to No. 13 of the present invention in which the amount of P is 0.05% or more, the amount of P is significantly improved. ○ Intervals 14 to N0.19 are examples in which the amount of S is changed in a steel type with approximately 0.7% Si, but in the case of floors 14 to 17 of the present invention, which have S of 0.005% or less, the amount of S exceeds that range. Kameiru N
0.18, both iron loss and magnetic flux density are better values than floor 19. ON1120 to 11k125 have low Sol and Aβ amounts in steel types with approximately 0.5% Si! This is an example in which the change was made within the 65 range, but S o 12. A7! O,OO2%
Inventive Examples 11b, 204+, and 23 below have So6. A
jl! It has lower core loss and higher magnetic flux density than N025 and 24, which exceeds this range. (4) On page 21, line 11 of the specification, the statement "900°C or higher" will be corrected to "850°C."that's all

Claims (2)

[Claims] (1) C0.005% or less, Si0.1-1.0%, M
r0.20% or less, P0.050-0.200%, S0
．． 005% or less, Sol. A steel material with less than 0.002% Al remaining Fe and unavoidable impurities is hot rolled at a rolling end temperature of 700°C or higher and within the ferrite range, and then coiled at a temperature of 600 to 680°C. , followed by descaling, cold rolling, and annealing. A method for producing a non-oriented electrical steel sheet with high magnetic flux density. (2) C0.005% or less, Si0.1-1.0%, M
n0.20% or less, P0.05-0.200%, S0.
005% or less, Sol. A steel material consisting of 0.150 to 1.0% Al and the balance being Fe and unavoidable impurities is hot rolled at a rolling end temperature of 700°C or higher and within the ferrite range, and then at a temperature of 600 to 680°C. A method for producing a non-oriented electrical steel sheet with high magnetic flux density, which comprises winding, followed by descaling, cold rolling, and annealing.