JP2014114490A - Method for producing grain oriented silicon steel sheet having excellent magnetic property - Google Patents

Abstract

A method of manufacturing a grain-oriented electrical steel sheet that meets the demand for further reduction in iron loss is provided.
A steel slab having a predetermined composition is hot-rolled at 1300 ° C. or lower, subjected to hot-rolled sheet annealing as necessary, and then cold-rolled by a single rolling to cool the final sheet thickness. In the manufacturing method of the grain-oriented electrical steel sheet consisting of a series of steps, after the primary recrystallization annealing and then applying the secondary recrystallization annealing after the primary recrystallization annealing,
The work roll diameter during the cold rolling is 250 mm or more, and the amount of S in the steel sheet increases from 100 ppm to 400 ppm by weight after the primary recrystallization annealing until the completion of the secondary recrystallization. Apply sulfur treatment.
[Selection] Figure 1

Description

  The present invention relates to a method for producing a grain-oriented electrical steel sheet suitable for a core material such as a transformer.

  The grain-oriented electrical steel sheet is mainly used as an iron core of a transformer and is required to have excellent magnetization characteristics, particularly low iron loss. For that purpose, it is important to highly align the secondary recrystallized grains in the steel sheet with the (110) [001] orientation (Goss orientation) and to reduce impurities in the product.

  Conventionally, such a grain-oriented electrical steel sheet is heated to 1300 ° C. or higher by heating a slab containing about 4.5 mass% or less of Si and an inhibitor component such as MnS, MnSe, AlN, etc. Then, after hot rolling and hot-rolled sheet annealing as necessary, the final sheet thickness is obtained by one or more cold rollings sandwiching intermediate annealing, followed by primary recrystallization annealing in a wet hydrogen atmosphere After performing primary recrystallization and decarburization, and further applying an annealing separator mainly composed of magnesia (MgO), the secondary recrystallization and inhibitor components are purified at 1200 ° C. for about 5 hours. It has been manufactured by performing final finish annealing (for example, Patent Document 1, Patent Document 2, and Patent Document 3).

In other words, precipitates (inhibitor components) such as MnS, MnSe, and AlN are contained in the slab stage, and these inhibitor components are once solid-dissolved by high-temperature slab heating exceeding 1300 ° C and finely precipitated in the subsequent process. A process of developing secondary recrystallization has been adopted.
However, in the manufacturing process of the above-mentioned grain-oriented electrical steel sheet, since slab heating at a high temperature exceeding 1300 ° C. was necessary, its manufacturing cost is extremely high, and it cannot meet the recent demand for reduction in manufacturing cost. I left a problem.

  On the other hand, in Patent Document 4, even if the inhibitor component is not included in the slab, the amount of S in the ground iron is increased after the primary recrystallization annealing and before the secondary recrystallization is completed. A technique (“sulfurization method”) capable of causing subsequent recrystallization is disclosed.

Further, as described above, after performing the cold rolling twice of intermediate annealing on the hot rolled sheet of electromagnetic steel to obtain the final sheet thickness, decarburization annealing and then applying the annealing separator and then finishing annealing. In the manufacturing process of a series of unidirectional electrical steel sheets to be applied, the cold rolling equipment used at the time of cold rolling is roughly divided into the following two.
That is, one is a multi-high rolling mill to which a small-diameter work roll is applied, and among them, a Sendzimir rolling mill is often used. The other is a tandem rolling mill, which can produce an electromagnetic steel sheet with high efficiency as disclosed in Patent Document 5.

Japanese Patent Publication No.40-15644 Japanese Patent Publication No.51-13469 Japanese Patent Publication No.62-56927 Japanese Patent No. 4321120 JP-A-61-132205 JP-A-6-65754 JP-A-6-65755 JP-A-6-299366

  However, the vulcanization treatment described in Patent Document 4 described above uniformly disperses S that has entered the steel during the period from the temperature raising process of the secondary recrystallization annealing to just before the secondary recrystallization. Therefore, the secondary recrystallization itself tends to be unstable. In particular, when performing coil annealing, there is a problem that the formation of secondary recrystallization tends to be more unstable because it is difficult to make the temperature in the coil and the atmosphere between the steel plate layers constant.

Although tandem rolling has the merit that it can be manufactured with high efficiency, the tandem rolled electrical steel sheet has a problem in that it has inferior electromagnetic properties than the electrical steel sheet rolled with a small diameter work roll such as a Sendzimir mill due to various factors. .
This is due to the phenomenon that the amount of rolling oil introduced into the roll bite is increased by high-speed rolling by tandem rolling, the rolling oil is enclosed between the steel plate and the roll, and the steel plate surface is crushed during rolling. The steel sheet surface has local irregularities called oil pits, which degrade the surface properties of the steel sheet, so the subscale that is mainly composed of firelite and silica formed on the steel sheet surface by the subsequent primary recrystallization annealing. It is presumed that this is a problem that arises from having a great influence on properties.

In addition, Sendzimir rolling to which a small-diameter work roll is applied has been considered advantageous from the viewpoint of formation of a texture that influences the selectivity to the Goss orientation during secondary recrystallization.
Therefore, when performing tandem rolling to improve productivity in the cold rolling stage when manufacturing electromagnetic steel sheets, there are problems of surface roughness and texture formation of the rolled sheets, and the magnetic properties are based on Sendzimir rolling. There was a problem that it was inferior to the small diameter rolling.

  Inventors consider the rolling temperature, rolling speed, work roll roughness, work roll diameter, etc. in more detail while keeping in mind the above-mentioned comparison between Sendzimir rolling and tandem rolling, and applying the vulcanization method As a result of searching for an optimal cold rolled structure for the present invention, the present invention described below was reached.

  The present invention has been developed in view of the above-described present situation, and an object thereof is to propose a grain-oriented electrical steel sheet that meets the demand for further reduction in iron loss.

First, the experimental results that led to the completion of the present invention will be described.
In mass% or mass ppm, C: 250ppm, Si: 3.40%, Mn: 0.08%, S: 15ppm, Se: 8ppm, Al: 50ppm, N: 30ppm and Sb: 0.02%, the balance being Fe and inevitable A steel slab composed of impurities is continuously cast, heated to 1200 ° C, then hot rolled into a 2.6mm thick hot rolled sheet, then hot rolled at 1000 ° C, and then pickled. And finished to a thickness of 0.30 mm by cold rolling.
At this time, using a tandem mill, a Sendzimir mill and two rolling mills, and increasing the amount of coolant and injecting it onto the steel sheet surface, cold rolling with a rolling temperature suppressed to around 80 ° C, processing heat generation or pass A total of four conditions were carried out by performing warm rolling at about 200 ° C. at the time of final rolling by interaging.

  In addition, the effect of the rolling speed was examined by implementing two conditions, a low speed rolling with a final sheet thickness of less than 200 rpm and a high speed rolling with a speed greater than 600 rpm. Furthermore, the influence of the work roll diameter was investigated using the wear of the work roll.

After finishing to a final plate thickness of 0.30 mm, each coil was degreased and decarburized and annealed in a wet hydrogen atmosphere at 850 ° C. Next, an annealing separator containing MgO as the main component and magnesium sulfate added at 10 parts by mass with respect to 100 parts by mass of the annealing separator was applied to the steel sheet, and a final finish annealing was performed at 1150 ° C. for 5 hours. As the atmosphere gas for final finish annealing, purification was performed using N ₂ gas during the temperature rise and H ₂ gas after reaching 1150 ° C. The amount of S that entered the steel during the final finish annealing was 220 ppm. Subsequently, after removing the unreacted separating agent, an insulating coating mainly composed of colloidal silica and Al phosphate was formed at 850 ° C. to obtain a product plate.

An Epstein sample was cut out from each product along the rolling direction, and the _iron loss value W _17/50 (W / kg) and the magnetic flux density B ₈ (T) at a magnetic flux density of 1.7 T and a frequency of 50 Hz were measured. Of the cold rolling conditions, the work roll diameter is plotted in FIG. 1 with the horizontal axis as the work roll diameter and the magnetic flux density B ₈ as the vertical axis.

From FIG. 1, when the secondary recrystallization is applied to the component system that does not contain the low Al inhibitor component, the effect of the cold rolling work roll diameter becomes the largest, and the work roll diameter It was found that a high magnetic flux density can be obtained under the condition of 250 mm or more.
The present invention is based on the above findings.

That is, the gist configuration of the present invention is as follows.
1. In mass%, Si: 2 to 8%, Mn: 0.5% or less, Al content is 0.01% or less, N content is 0.005% or less, S, Se and O are each less than 50 mass ppm, and C is 400 The steel slab composed of Fe and inevitable impurities is mass ppm or less, and the steel slab is subjected to hot rolling at 1300 ° C or less and, if necessary, hot-rolled sheet annealing, followed by cold rolling by a single rolling. In the method for producing a grain-oriented electrical steel sheet comprising a series of steps, a cold-rolled sheet having a final sheet thickness by rolling, then, after primary recrystallization annealing, and then applying secondary recrystallization annealing after applying an annealing separator,
The work roll diameter at the time of the cold rolling is 250 mm or more, and between the primary recrystallization annealing and the completion of the secondary recrystallization, S in the steel sheet is 100 mass ppm or more and 400 mass ppm or less. A method for producing a grain-oriented electrical steel sheet having excellent magnetic properties, characterized by performing a treatment.

2. 2. The method for producing a grain-oriented electrical steel sheet having excellent magnetic properties according to 1 above, wherein the cold rolling is performed with a tandem rolling mill.

3. The steel slab is further composed of mass%, Ni: 0.03-1.50%, Sn: 0.01-1.50%, Sb: 0.005-1.50%, Cu: 0.03-3.0%, P: 0.03-0.50%, Mo: 0.005 The method for producing a grain-oriented electrical steel sheet having excellent magnetic properties according to the above 1 or 2, characterized by containing at least one selected from -0.10% and Cr: 0.03-1.50%.

  According to the present invention, a grain-oriented electrical steel sheet with lower iron loss can be obtained stably.

Each condition of the cold rolling is a graph showing the work roll diameter horizontal axis, the magnetic flux density B ₈ as ordinate.

  Hereinafter, the present invention will be specifically described. In addition, unless otherwise indicated, "%" and "ppm" display regarding the following steel plate components mean mass% (mass%) or mass ppm (mass ppm).

[After the primary recrystallization annealing until the completion of the secondary recrystallization, a sulfur increasing treatment is performed so that S in the steel sheet becomes 100 ppm or more and 400 ppm or less]
As for the amount of S, the effect of improving the magnetic properties appears by sulfiding at 100 ppm or more. On the other hand, the upper limit is preferably 400 ppm or less for the formation of a forsterite film formed during the secondary recrystallization annealing, since excessive oxidation proceeds with excessive oxidation and the coating quality deteriorates.

Next, points related to manufacturing will be described. In the present invention, unless otherwise specified, a conventionally known method for producing grain-oriented electrical steel sheets that does not use high-temperature slab heating is followed.
First, the molten steel component of the present invention will be described.
In the present invention, the amount of Al is suppressed to 0.01% or less during steel melting. This is because the present invention assumes a slab heating temperature of 1300 ° C. or less on the premise of a process that does not use AlN as an inhibitor. It is because it becomes a disturbance factor of secondary recrystallization as a precipitate. Therefore, the Al amount needs to be suppressed to 0.01% or less.

  Although N can be removed in the subsequent steps, N is limited to 0.005% or less because removal takes time and cost if the content is too large.

  When C exceeds 400 ppm, there is an effect on the rolling temperature and rolling speed in the cold rolling of the present invention, and even when the work roll diameter in the range according to the present invention is 300 mm or more, good magnetic properties are obtained. May not be obtained. This is estimated to be the effect of carbide precipitation due to interpass aging, but the effect is complex and unclear. In any case, since there is a possibility of causing instability of secondary recrystallization, in the present invention, C is limited to 400 ppm or less. Further, the lower limit is not particularly required, but about 30 ppm is preferable in terms of magnetic characteristics.

  Si is an element effective in increasing the electrical resistance of steel and improving iron loss. However, if the content is less than 2.0%, the effect of addition is poor. On the other hand, if it exceeds 8.0%, the workability is remarkable. The amount of Si needs to be in the range of 2.0 to 8.0% because the magnetic flux density also decreases. Preferably, it is 2.0 to 4.5% of range.

  Mn is an element necessary for improving the hot workability, but if it exceeds 0.5%, the magnetic flux density of the product plate is lowered, so it is necessary to make it within a range of 0.5% or less. Further, the lower limit is not particularly required, but is preferably about 0.005% from the viewpoint of advantageous expression of the addition effect.

As described above, in the present invention, since Al is reduced, there is no utilization of a so-called inhibitor mainly composed of AlN. In this case, in order to obtain a grain-oriented electrical steel sheet having a high magnetic flux density, S: 50 ppm (0.005%) or less and Se: 50 ppm (0.005%) or less are required. This is because a steel component system that does not contain an inhibitor component that exhibits a strong suppressive force has a large effect on the grain growth property in primary recrystallization due to impurities.
Further, the amount of O needs to be 50 ppm (0.005%) or less. This is because oxides as inclusions adversely affect the magnetic properties.

  From the viewpoint of improving the magnetic flux density, the amount of S is better as the amount added is larger. However, when performing low-temperature slab heating, it is difficult to precipitate with good controllability as an inhibitor such as MnS. However, it is desirable to increase the steel sheet by performing a vulcanization process after the primary recrystallization annealing until the completion of the secondary recrystallization. Since the secondary recrystallization annealing is performed in a batch manner, the rate of temperature increase is generally slow, and it is suitable for uniformly dispersing S that has penetrated into the steel by the vulcanization treatment.

  In addition to the above basic components, in the present invention, Ni: 0.03-1.50%, Sn: 0.01-1.50%, Sb: 0.005-1.50%, Cu: 0.03-3.0%, P: 0.03-0.50%, At least one selected from Mo: 0.005 to 0.10% and Cr: 0.03 to 1.50% can be appropriately contained.

  Ni is a useful element that improves the magnetic properties by improving the hot-rolled sheet structure. However, if it is less than 0.03%, the effect of improving the magnetic properties is small. On the other hand, if it exceeds 1.5%, secondary recrystallization becomes unstable and the magnetic properties deteriorate, so when adding Ni, the range of 0.03 to 1.5% To do.

Sn, Sb, Cu, P, Mo, and Cr are elements that are useful for improving the magnetic properties, but if any of them is less than the lower limit of each component described above, the effect of improving the magnetic properties is small. When the above upper limit amount of each component is exceeded, the development of secondary recrystallized grains is inhibited. Therefore, when added, Sn: 0.01 to 1.50%, Sb: 0.005 to 1.50%, Cu: 0.03 to The range is 3.0%, P: 0.03-0.50%, Mo: 0.005-0.10%, and Cr: 0.03-1.50%.
The balance other than the above components is inevitable impurities and Fe.

Next, the manufacturing process of the present invention will be described.
The steel slab adjusted to the above preferable component composition range is subjected to hot rolling without being reheated or after being reheated. When the slab is reheated, the reheating temperature is desirably about 1000 ° C. or higher and about 1300 ° C. or lower.

In the present invention, since AlN is not used as an inhibitor, it is not necessary to completely dissolve it by high-temperature heating. Similarly, since MnS has an S content of 50 ppm or less, it cannot be used as an inhibitor, so there is no need for high-temperature heating.
The hot-rolled sheet obtained by hot rolling is subjected to hot-rolled sheet annealing as necessary, and then cold-rolled once to obtain a final cold-rolled sheet. This cold rolling may be performed at room temperature, or may be warm rolling in which the steel sheet temperature is raised to a temperature higher than room temperature, for example, about 250 ° C. However, it is important that the cold rolling performed in the present invention is performed with a work roll diameter of 250 mm or more. The work roll diameter is preferably 320 mm or more.

  On the other hand, it is considered that the temperature and the rolling speed of cold rolling do not have a great influence in the present invention. Moreover, although the difference between tandem rolling and Sendzimir rolling is not clear, from the above experimental results, the effect of warm interpass aging, which is the greatest feature of the present invention, is not so large, Due to its size, tandem rolling tends to be advantageous.

Here, the reason why the magnetic flux density increases when the work roll diameter is 250 mm or more is not clear, but the deformation within the roll bite varies depending on the work roll diameter, and especially the difference in shear strain introduced near the surface. It is estimated that it is caused by
That is, as the work roll diameter is larger, the steel sheet is less likely to undergo shear deformation, approaching simple compression, and the penetration behavior of S during the vulcanization process is different, so that the magnetic flux density is considered to increase.

In addition, the rolling texture formed during cold rolling also has a distribution in the plate thickness direction, but this distribution should also differ depending on the rolling deformation behavior. Therefore, it is considered that the combination of the strain distribution introduced and the texture distribution formed thereafter has a great influence on the intrusion of S and the resulting inhibition effect and secondary recrystallization behavior. In any case, in the case of a component composition that does not contain an inhibitor component and C is 400 ppm or less, the contribution of aging between passes as conventionally known is reduced, and the superiority of the Sendzimir mill is lost. It is considered a thing.
The upper limit value of the work roll diameter is not particularly set, but is 800 mm or less in a tandem rolling mill due to the structure of the rolling mill.

  Next, primary recrystallization annealing is applied to the final cold rolled sheet. The primary purpose of this primary recrystallization annealing is to adjust the primary recrystallization grain size optimal for secondary recrystallization by primary recrystallization of a cold rolled sheet having a rolled structure. For this purpose, it is desirable that the annealing temperature of the primary recrystallization annealing is about 800 ° C. or more and less than 950 ° C. The second purpose is decarburization. If the product plate contains more than 30ppm of carbon, iron loss will deteriorate. Note that the annealing atmosphere at this time is preferably a wet hydrogen nitrogen or wet hydrogen argon atmosphere.

After the primary recrystallization annealing, an annealing separator is applied to the surface of the steel plate. In order to form a forsterite film on the steel sheet surface after secondary recrystallization annealing, it is necessary to use magnesia (MgO) as the main component of the annealing separator. As the separating agent main agent, an appropriate oxide having a melting point higher than the secondary recrystallization annealing temperature such as alumina (Al ₂ O ₃ ) or calcia (CaO) can be used.
Thereafter, secondary recrystallization annealing is performed. By this secondary recrystallization annealing, a crystal structure highly accumulated in the Goth orientation is obtained, and good magnetic properties can be obtained.

In the present invention, there are various methods for increasing the amount of S in steel as follows.
From the viewpoint of continuous treatment, a gas vulcanization method in which annealing treatment is performed in H ₂ S gas is advantageous. In this case, H ₂ or NH ₃ decomposition gas is used as the carrier gas. Fe and H ₂ S are very easy to react and produce iron sulfide even at low temperatures, so they are suitable for vulcanization. When NH ₃ decomposition gas is used as a carrier gas, nitriding occurs with vulcanization, but in the present invention, Al is not more than 100 ppm, so that sufficient AlN is not generated to exhibit the inhibitor effect.

  In addition, a method of immersing in an aqueous solution in which S powder is added to an aqueous NaOH solution, and a method of electrolysis using a steel plate as a cathode in an aqueous solution of sodium thiosulfate and boric acid are also effective.

  It is also possible to use a salt bath. As the neutral bath, an S compound is added to sodium sulfate, and as the reducing bath, a salt bath in which an S compound is added to sodium cyanide or potassium cyanide is used. At the same time, a nitriding reaction occurs. In addition, since all the above-mentioned processes are continuous processes, the amount of vulcanization to the steel sheet can be made uniform.

  There is also a method of adding a trace amount of sulfate or sulfide into the annealing separator applied after the primary recrystallization annealing.

  In any case, it is necessary for the sulfur content in the steel sheet to be 100 ppm or more and 400 ppm or less between the time after the primary recrystallization annealing and the completion of the secondary recrystallization by the above vulcanization treatment.

In the present invention, when sulfate or sulfide is added to the annealing separator, Ag, Al, Ba, Ca, Co, Cr, Cu, Fe, In, K, Li, Mg, Mn, Na, Ni, One or more selected from the sulfates or sulfides of Sn, Sb, Sr, Zn, and Zr can be preferably used.
In the secondary recrystallization annealing, N ₂ , Ar, or a mixed gas thereof is advantageously suitable for the annealing atmosphere. H ₂ is desirable for purification after secondary recrystallization.

  When the grain-oriented electrical steel sheet is used for a core material such as a transformer, it is used by being laminated, so that an insulating layer for interlayer insulation is required. As the additionally applied insulating coating, a generally used inorganic coating can be used for the grain-oriented electrical steel sheet. In particular, a coating having a tension-imparting effect is extremely effective in combination with a grain-oriented electrical steel sheet in which the steel sheet surface is smoothed in order to achieve low iron loss. As a type of tension-imparting coating, a coating containing silica that reduces the thermal expansion coefficient is effective, and the phosphate-colloidal silica-chromic acid system that has been used for grain-oriented electrical steel sheets having a forsterite film has been used. A coating or the like is preferable from the viewpoint of its effect and cost, uniform processability, and the like. The thickness of the coating is preferably in the range of about 0.3 μm or more and 10 μm or less from the viewpoint of tension application effect, space factor, film adhesion, and the like.

  In addition, it is also possible to apply oxide-based films such as boric acid-alumina proposed in Patent Document 6, Patent Document 7, and Patent Document 8 as the tension coating.

[Example 1]
The slab having the composition of steel ingot symbols 1 to 5 shown in Table 1 was heated to 1200 ° C. and hot-rolled to obtain a 2.6 mm thick hot rolled coil. Next, this hot-rolled coil is annealed at 1000 ° C., then pickled, and finished to a thickness of 0.30 mm with a Sendzimir mill or tandem mill, and the coil is used for magnetic evaluation and for the amount of sulfur increase during final annealing. Divided into two. The cold rolling was performed at a cold condition of 60 ° C. to 90 ° C. and a warm condition of 175 ° C. to 205 ° C. by adjusting the amount of coolant. Moreover, the influence of the work roll diameter was also evaluated.

After degreasing, after performing decarburization annealing in a wet hydrogen atmosphere at 850 ° C., 5 to 15 parts by mass of magnesium sulfate is added to or not added to 100 parts by mass of the annealing separator mainly composed of MgO. An annealed separator was applied. Subsequently, the coil for magnetic evaluation was heated to 1075 ° C. in a mixed atmosphere of Ar and N ₂ , and purification annealing at 1200 ° C. was performed in an H ₂ atmosphere. Then, after removing the unreacted separating agent, an insulating coating composed mainly of colloidal silica and magnesium phosphate was formed at 800 ° C. On the other hand, the coil for investigating the amount of vulcanization was heated to 1075 ° C. and then cooled, and the amount of S in the steel sheet was analyzed.
From the product thus obtained, an Epstein-size test piece was cut out along the rolling direction, and the iron loss value W _17/50 and the magnetic flux density B ₈ at 50 Hz AC excitation at a magnetic flux density of _{1.7 T} were measured. Table 2 summarizes the rolling conditions, the contents of Al and C, the amount of sulfur increase (increase S), and the obtained magnetic properties.

  As is apparent from Table 2, the conditions F, G and J satisfying the present invention showed good magnetic properties. On the other hand, the conditions B to D and H where the steel components are removed, the conditions A where the amount of vulcanization is insufficient, and the conditions E and I where the work roll diameter is out of the scope of the present invention are all good magnetic properties. It was not obtained.

[Example 2]
The slab having the composition of steel ingot symbols 2-1 to 2-6 shown in Table 3 was hot-rolled to 1200 ° C. to obtain a hot-rolled coil having a thickness of 2.6 mm. Next, the hot rolled coil was annealed at 1000 ° C., pickled, and then finished to a thickness of 0.30 mm by a tandem rolling mill. Cold rolling was performed under cold conditions of 75 ° C. by adjusting the amount of coolant, and the work roll diameter was 350 mm.
After degreasing, decarburization annealing was performed in a wet hydrogen atmosphere at 850 ° C., and 10 parts by mass of magnesium sulfate was added to 100 parts by mass of an annealing separator mainly composed of MgO. Then heated in a mixed atmosphere of Ar and N ₂ up to 1075 ° C., purification annealing of 1200 ° C. was performed in an H ₂ atmosphere. Then, after removing the unreacted separating agent, an insulating coating composed mainly of colloidal silica and magnesium phosphate was formed at 800 ° C.
From the product thus obtained, an Epstein-size test piece was cut out along the rolling direction, and the iron loss value W _17/50 and the magnetic flux density B ₈ at 50 Hz AC excitation at a magnetic flux density of _{1.7 T} were measured. Table 3 shows the measurement results of the magnetic properties together with the above component compositions.

  As is apparent from the table, the conditions satisfying the present invention all exhibit good magnetic properties.

Claims (3)

In mass%, Si: 2 to 8%, Mn: 0.5% or less, Al content is 0.01% or less, N content is 0.005% or less, S, Se and O are each less than 50 mass ppm, and C is 400 The steel slab composed of Fe and inevitable impurities is mass ppm or less, and the steel slab is subjected to hot rolling at 1300 ° C or less and, if necessary, hot-rolled sheet annealing, followed by cold rolling by a single rolling. In the method for producing a grain-oriented electrical steel sheet comprising a series of steps, a cold-rolled sheet having a final sheet thickness by rolling, then, after primary recrystallization annealing, and then applying secondary recrystallization annealing after applying an annealing separator,
The work roll diameter at the time of the cold rolling is 250 mm or more, and between the primary recrystallization annealing and the completion of the secondary recrystallization, S in the steel sheet is 100 mass ppm or more and 400 mass ppm or less. A method for producing a grain-oriented electrical steel sheet having excellent magnetic properties, characterized by performing a treatment.   The method for producing a grain-oriented electrical steel sheet having excellent magnetic properties according to claim 1, wherein the cold rolling is performed with a tandem rolling mill. The steel slab is further mass%, Ni: 0.03-1.50%, Sn: 0.01-1.50%, Sb: 0.005-1.50%, Cu: 0.03-3.0%, P: 0.03-0.50%, Mo: 0.005-0.10. % And Cr: 0.03 to 1.50%. The method for producing a grain-oriented electrical steel sheet with excellent magnetic properties according to claim 1 or 2, comprising at least one selected from 0.03 to 1.50%.

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