JP6489089B2 - Method for producing hot rolled coil and non-oriented electrical steel sheet - Google Patents

Description

  The present invention relates to a method for producing a hot rolled coil and a non-oriented electrical steel sheet.

  Conventionally, the thickness control method in cold rolling has been provided with thickness gauges at the front and rear of the stand, or one of them, so that the reduction position of each stand (rolling load), tension between the stands, etc. Is generally controlled by feedback and feedforward control. However, even if fluctuations occur, even if information on the front stage is input to the rear stage by feedforward or fed back and input to the front stage, the plate thickness fluctuations are corrected sufficiently for short period and steep fluctuations. There is a problem that it is difficult.

  As the short period and steep fluctuation, there is a fluctuation in the winding pitch of a hot rolled coil (hereinafter also referred to as a hot rolled coil).

  In the production of hot-rolled coils before cold rolling, in order to promote recrystallization during hot-rolled coil storage, when the coiling temperature in hot-rolling is increased, depending on how the hot-rolled coil is placed, that is, by the storage method, A temperature distribution in the circumferential direction of the coil may occur. For example, the surface of the coil that is in contact with the air is cooled by air cooling, but is kept warm at a location where it is in contact with another hot coil, and a temperature distribution is generated between the surface of the air cooled coil and the location where the temperature is kept. Due to the change in structure caused by this temperature distribution, the difference in hardness and friction coefficient between the surface of the coil that has been air-cooled and the location where the heat is retained increases. In addition, for example, a location in contact with another cold coil, or a location in contact with the ground or the skid for fixing is rapidly cooled, so that a temperature distribution occurs between the surface of the air-cooled coil, Similar organizational changes occur.

  Such a structure change in the circumferential direction of the hot-rolled coil causes a plate thickness variation in the subsequent cold rolling. Patent Document 1 discloses a method of gradually cooling a coil to a predetermined temperature in order to suppress sheet thickness fluctuations in cold rolling caused by a structure change in the circumferential direction of the hot rolled coil. However, the temperature difference between the part that is in contact with the ground and the part that is air-cooled due to the difference in heat transfer coefficient between the heat removal from the ground where the outer periphery (steel plate surface) of the coil contacts and the other air-cooled part is only by slow cooling. Occurs, the structure changes, and the problem that the thickness variation at the time of subsequent cold rolling cannot be sufficiently suppressed occurs. Patent Document 2 discloses a device for overturning a coil. Patent Document 3 discloses a cooling convection plate that is used when a coil is placed in an up-end state. However, these documents do not describe the composition of steel, coil winding temperature, and the like. In addition, the cooling convection plate disclosed in Patent Document 3 changes the area of the opening between the inner peripheral side and the outer peripheral side to prevent scuffing, but the surface on which the coil is mounted (mounting surface) There is no description regarding the ratio (opening ratio) of the total area of the apertures to the area of.

Japanese Patent Publication No. 1-18129 Japanese Patent No. 378397 Japanese Patent Publication No. 7-816

  For hot-rolled coils that require winding at a high temperature, the steel plate surface is placed in the direction of gravity (the method of placing it in the down-end state, that is, the method of placing the coil in the horizontal direction), the ground, the table, etc. When the coil is placed on the coil, the temperature difference between the part that contacts the ground or the pedestal and the part that does not contact increases, so that there are periodic characteristic fluctuations in the circumferential direction of the coil, that is, in the longitudinal direction of the steel strip. Will occur. In that case, when cold rolling is performed in the subsequent manufacturing process, there arises a problem that the plate thickness varies due to periodic hardness variation and friction coefficient variation.

  Therefore, the present invention solves the above-mentioned problems, and can suppress fluctuations in the circumferential characteristics of the coil with respect to the coil wound at high temperature, suppresses fluctuations in the sheet thickness during cold rolling, and stably performs cold rolling. It aims at providing the manufacturing method of the hot rolling coil which can implement.

Means of the present invention for solving the above problems are as follows.
[1] C: 0.01 mass% or less, Si: 5.0 mass% or less, Mn: 0.05 to 3.0 mass%, sol. Al: 0.0050 mass% or less or 0.2 to 2.0 mass%, P: 0.20 mass% or less, S: 0.010 mass% or less and N: 0.010 mass% or less, with the balance being Fe and inevitable A hot-rolled coil comprising hot rolling a steel having a component composition composed of impurities, forming a coiled coil at a temperature of 550 ° C. or higher, and then placing the coil in an up-end state Manufacturing method.
However, in the component composition, when Si is 1.5 mass% or more, sol. Al is 0.0050 mass% or less, and when Si is less than 1.5 mass%, sol. Al is 0.2 to 2.0 mass%.
[2] The coil wound in the coil shape is placed in an up-end state within 30 minutes from the completion of winding, and the surface temperature of the outer periphery of the coil is 300 ° C. or less in the state of the placement. The method for producing a hot-rolled coil according to [1], wherein
[3] The method for manufacturing a hot-rolled coil according to [1] or [2], wherein the coil is overturned so that positions of upper and lower side surfaces of the coil placed in the up-end state are switched. .
[4] The method for manufacturing a hot-rolled coil according to any one of [1] to [3], wherein the coil is mounted on a mounting table having an aperture ratio of 0.3 or more.
[5] A non-direction characterized by cold-rolling and annealing a steel strip delivered from a hot-rolled coil obtained by the method for producing a hot-rolled coil according to any one of [1] to [4] Method for producing an electrical steel sheet.

  According to the present invention, hot rolling that can suppress the characteristic fluctuation in the circumferential direction of the coil with respect to the coil wound at high temperature, suppress the fluctuation of the plate thickness at the time of cold rolling, and can stably perform the cold rolling. Coil can be manufactured.

FIG. 1 is a side view for explaining an example of a method for bringing a coil into an up-end state. FIG. 2 is a side view showing an example of a mounting state of the coil according to the present invention. FIG. 3 is a top view showing an example of a mounting table according to the present invention.

  In the present invention, C: 0.01 mass% or less, Si: 5.0 mass% or less, Mn: 0.05 to 3.0 mass%, sol. Al: 0.0050 mass% or less or 0.2 to 2.0 mass%, P: 0.20 mass% or less, S: 0.010 mass% or less and N: 0.010 mass% or less, with the balance being Fe and inevitable This is a method for producing a hot-rolled coil in which a steel having a component composition consisting of impurities is hot-rolled and then coiled into a coil at a temperature of 550 ° C. or higher, and then the coil is placed in an up-end state. . However, in the component composition, when Si is 1.5 mass% or more, sol. Al is 0.0050 mass% or less, and when Si is less than 1.5 mass%, sol. Al is 0.2 to 2.0 mass%.

  Referring to FIG. 1, the coil 10 wound into the coil shape is transferred to the coil overturning device 20 and then overturned by the coil overturning device 20 so as to support its own weight on one side surface 12a of the coil 10. (FIG. 1 (a)), an up-end state, that is, a state in which the axial direction of the coil is along the direction of gravity (FIG. 1 (b)), the ground, a table (hereinafter simply referred to as “table, etc.”) ). At that time, the coil 10 is preferably placed on a coil mount 30 as shown in FIG. Moreover, it is preferable that the coil 10 is mounted so that structures, such as a fall apparatus, and arbitrary structures 40, such as another coil, may not contact the outer periphery 14 (steel plate surface) of the coil 10. FIG. Furthermore, it is preferable that the distance L between the coil 10 and the arbitrary structure 40 is 100 mm or more. By doing so, the influence of the heat retention and heat removal by contact with the outer periphery 14 of the coil 10 and the arbitrary structures 40 can be reduced, and the temperature unevenness in the circumferential direction of the coil 10 can be further reduced. Further, by securing the distance L to 100 mm or more, the heat retention effect due to radiation can be further reduced, and the temperature unevenness in the circumferential direction of the coil 10 can be further reduced. As an application example, a heat insulating material or the like may be wound around the circumferential direction of the coil 10 placed in an up-end state. By doing so, the temperature unevenness of the coil 10 can be further reduced, and the recrystallization can be promoted by keeping the temperature of the coil 10 high by a uniform heat retention effect.

  Next, the relationship between the characteristics of the final product plate (non-oriented electrical steel sheet) using the hot rolled coil of the present invention and the component composition will be described.

  C is an element that causes magnetic aging and increases iron loss. Particularly, when C exceeds 0.01 mass%, an increase in iron loss becomes remarkable, so that it is limited to 0.01 mass% or less. Preferably it is 0.0050 mass% or less. In addition, about a minimum, since it is so preferable that there is little, it does not prescribe | regulate.

  Si is an element effective for increasing the electric resistance of steel and reducing iron loss. Therefore, it is preferable to add. When reducing Al having the same effect as Si, Si is preferably added in an amount of 1.5 mass% or more. However, if Si exceeds 5.0 mass%, not only the magnetic flux density is lowered, but also the steel becomes brittle and cracks are generated during cold rolling, resulting in a significant reduction in manufacturability. Therefore, the upper limit is set to 5.0 mass%. Preferably it is the range of 0.2-3.8 mass%.

  Mn combines with S to form MnS and has the effect of preventing hot brittleness due to FeS. Moreover, like Si, it is an element effective in increasing the electrical resistance of steel and reducing iron loss. Therefore, in the present invention, 0.05 mass% or more of Mn is contained. On the other hand, since magnetic flux density will fall if it exceeds 3.0 mass%, an upper limit shall be 3.0 mass%. Preferably, it is the range of 0.25-1.5 mass%.

  Al, like Si, is an element that is effective in increasing the electrical resistance of steel and reducing iron loss. However, from the viewpoint of recycling scrap as a raw material for cast iron, Al is desired to be less than 0.05 mass%, and the smaller the Al content, the better. In the present invention, in order to improve the texture and increase the magnetic flux density, the content of Al is further reduced. It is limited to 0.0050 mass% or less with Al (acid-soluble Al). sol. Al is more preferably 0.0020 mass% or less. sol. When Al is limited to 0.0050 mass% or less, the Si content is set to 1.5 mass% or more. Moreover, when suppressing Si addition amount (Si content is less than 1.5 mass%), Al having the same effect as Si is sol. Al (acid-soluble Al) is contained in an amount of 0.2 to 2.0 mass%.

  P is a useful element that has a large effect of increasing the hardness of steel with a small amount of addition, and is appropriately added according to the required hardness. However, excessive addition of P causes a decrease in cold rollability, so the upper limit is made 0.20 mass%. Preferably, it is the range of 0.040 mass%-0.15 mass%.

  Since S becomes sulfides and forms precipitates and inclusions, and deteriorates manufacturability (hot rollability) and magnetic properties of the final product plate, the smaller the S content, the better. In the case where importance is attached to the magnetic properties of the final product plate, it is preferably 0.010 mass% or less. In addition, since it is so preferable that there is little S, a minimum in particular is not prescribed | regulated.

  N is an element that deteriorates the magnetic properties, as in the case of C described above. In particular, in the case of a low Al material, the above-described adverse effect becomes significant, so that it is limited to 0.010 mass% or less. Preferably it is 0.0040 mass% or less. In addition, about a minimum, since it is so preferable that there is little, it does not prescribe | regulate.

  In addition to the above, a known element may be used for improving characteristics. In order to improve the magnetic flux density, it is preferable to contain a total of 0.01 to 0.2 mass% of one or two selected from Sb and Sn. In order to improve grain growth and reduce iron loss, it is preferable to contain one or more selected from the sulfide forming elements Ca, REM and Mg in a total amount of 0.001 to 0.02 mass%. It is. In either case, the effect is not obtained if the amount is less than the lower limit, and the effect is saturated if the upper limit is exceeded.

  When the hot-rolled steel sheet produced in such a component system is wound at a low temperature, recrystallization does not occur sufficiently during coil storage, and unrecrystallized parts called elongated grains remain, and crystal grains that are long in the rolling direction Will remain. If a steel strip paid out from such a coil is cold-rolled later, a vertical streak-like appearance defect will occur. Further, in the final product plate, it causes a decrease in magnetic properties such as a decrease in magnetic flux density. That is, cold rolling cannot be stably performed. Therefore, the winding temperature is set to 550 ° C. or higher. The winding temperature is preferably 600 ° C. or higher. However, an increase in coil winding temperature leads to an increase in temperature unevenness during coil storage. Therefore, it is not the way of placing the outer periphery 14 (steel plate surface) of the coil 10 in contact with the pedestal or the like, but by placing and storing the side surface 12a of the hot rolled coil in contact with the pedestal or the like in the circumferential direction of the coil. Recrystallization can be completed without causing temperature changes, i.e., structural changes or characteristic fluctuations in the circumferential direction of the coil, and it becomes possible to produce a steel sheet with small sheet thickness fluctuations during cold rolling. Although the temperature difference in the coil width direction (steel plate width direction) is enlarged by bringing the coil side surface 12a into contact with the pedestal or the like, unlike the rapid characteristic fluctuation in the coil circumferential direction, Since the thickness adjustment in the width direction of the steel sheet can be performed by adjusting the rolling load applied to both ends, it is possible to sufficiently control the thickness.

  Further, the time from when the coil 10 wound in the coil shape is placed in the up-end state after the completion of winding is preferably within 30 minutes, and more preferably within 15 minutes. This is because it is preferable that the coil 10 is not held for a long time in a state where a temperature difference occurs in the circumferential direction of the coil, and the shorter the time until the coil 10 is in the up-end state, the better. If the time until the coil 10 is placed in an up-end state exceeds 30 minutes from the completion of winding, the temperature difference in the circumferential direction of the coil increases, resulting in a difference in the structural change of the steel sheet, and the hardness and friction coefficient Etc. may change, leading to fluctuations in sheet thickness during cold rolling.

  Moreover, after mounting the coil 10 in an up-end state, it is preferable to continue the mounting in the state until the surface temperature of the outer periphery 14 of the coil becomes 300 ° C. or less. That is, after the coil 10 is placed in an up-end state, the outer periphery 14 of the coil 10 is in contact with a table or the like (down-end state) until the surface temperature of the outer periphery 14 of the coil 10 is 300 ° C. or lower. It is preferable not to return to). If the coil 10 is handled for a short time, the temperature distribution in the circumferential direction of the coil is not obtained even when the coil 10 is returned to the down-end state, which is not a problem. Therefore, in the present invention, if the time for the coil 10 to be in the down-end state is within 15 minutes per time, the mounting in the up-end state is assumed to have continued. However, if the coil 10 is held in a down-end state over a long time, for example, 15 minutes, and the outer periphery 14 of the coil 10 is held in contact with a table or the like, temperature unevenness in the circumferential direction of the coil 10 occurs, and the coil 10 is raised. The effect placed in the end state will fade. Moreover, when the surface temperature of the outer periphery 14 of the coil 10 is returned to the down-end state at a temperature higher than 300 ° C. and the state is continued, a temperature difference is caused in the coil circumferential direction, resulting in a difference in tissue change. . If the surface temperature of the outer periphery 14 of the coil 10 is 300 ° C. or less, it is difficult for the tissue change to proceed. Therefore, even if the coil 10 is returned to the down-end state, the effect of placing the coil 10 in the up-end state is effective. Maintained.

  Further, after placing the coil 10 in the up-end state, the coil 10 may be turned over so as to change the positions of the upper and lower side surfaces. That is, in FIG. 2, the coil 10 is turned over such that the lower side surface 12a is the upper side and the upper side surface 12b of the coil 10 is the lower side (the side surface 12b of the coil 10 is in contact with the coil mount 30). Also good. By performing such overturning, it is possible to suppress an increase in the temperature difference in the coil width direction that occurs when only one side surface of the coil 10 is in contact with the mounting table or the like. Therefore, changes in characteristics such as hardness in the coil width direction and friction coefficient can be further suppressed. Furthermore, the above-mentioned overturn may be performed a plurality of times. By performing the above-described overturning a plurality of times, it is possible to further suppress an increase in the temperature difference in the coil width direction, and to further suppress changes in characteristics such as hardness and friction coefficient in the coil width direction.

  Moreover, it is preferable that the above-described overturn is performed every time a certain time has elapsed after the coil 10 is placed in the up-end state. For example, after the coil 10 is placed in the up-end state, It is preferably performed every 2 hours, and more preferably every 0.5 to 1.0 hours. Further, the above-mentioned overturn is preferably performed every time the surface temperature of the outer periphery 14 of the coil 10 is lowered by a certain temperature after the coil 10 is placed in the up-end state. After the mounting in the state, it is preferably performed every time the surface temperature of the outer periphery 14 of the coil 10 decreases by 50 to 100 ° C., and more preferably every time the surface temperature decreases by 10 to 50 ° C.

  Moreover, although the coil 10 may be mounted on the ground, it is preferable to be mounted on a mounting stand from the point etc. which can reduce the tissue fluctuation | variation difference of a coil width direction more. As the mounting base, a coil mounting base 30 having an opening as shown in FIG. 3 is preferable. The coil mounting table 30 includes a plurality of openings 32 on the mounting surface of the coil 10 (the surface on which the coil 10 is mounted). The aperture ratio (total area of the opening / area of the mounting surface) of the coil mount 30 is preferably 0.3 or more. Here, the area of the mounting surface described above is an area obtained by the product of the vertical length X and the horizontal length Y of the mounting surface in FIG. In addition, in FIG. 3, although the shape of the opening part 32 of the coil mounting base 30 is made into the substantially square shape in planar view, it is not limited to this. For example, the planar view shape of the opening of the coil mount 30 may be a rectangle, a rhombus, a circle, or the like, or a triangle or a polygon that is a pentagon or more.

  Furthermore, it is preferable to secure a distance of 100 mm or more between the lower side surface 12a of the coil 10 and a surface without an opening (for example, a surface on which the coil mount 30 such as the ground is placed). For example, in the coil mount 30, the distance is set such that the thickness of the coil mount 30 is 100 mm or more, and the opening 32 is made to have a length of 100 mm or more in the thickness direction of the coil mount 30 from the mounting surface of the coil 10 ( It can be easily secured by forming at a depth. By placing the coil 10 on such a table and storing it, the cooling efficiency of the lower side surface 12a of the coil 10 is made closer to the upper side surface 12b, the influence of heat retention due to radiation is reduced, and the steel plate width direction is reduced. The temperature difference can be further reduced, that is, the difference in structure variation in the steel plate width direction can be further reduced. As a result, the plate thickness accuracy in the steel plate width direction during cold rolling can be further improved. If the opening ratio of the coil mount 30 is less than 0.3, the area where the lower side surface 12a of the coil in contact with the coil mount 30 is air-cooled is not sufficient, and the lower side surface 12a and the upper side of the coil 10 are on the upper side. There is a possibility that the temperature difference between the side surfaces 12b of the steel sheet increases, and the characteristics in the coil width direction, that is, the thickness accuracy in the steel sheet width direction during cold rolling may deteriorate. Further, if the distance between the lower side surface 12a of the coil 10 and the surface without the opening is short, the lower side surface 12a of the coil 10 is kept at a high temperature due to the influence of radiation. There is a concern that the temperature difference between the surfaces (12a, 12b) may increase.

  The present invention will be described in detail with reference to the following examples and comparative examples.

  A hot-rolled steel sheet having a plate thickness of 2.0 mm and a plate width of 1230 mm was wound into a coil shape under the conditions described in Table 1, and placed and stored. Thereafter, the steel strip discharged from the hot-rolled coil after placement and storage described above is pickled, cold-rolled to a thickness of 0.5 mm to obtain a cold-rolled steel sheet, and the thickness of the steel sheet in the longitudinal and width directions The variation value was measured and relative evaluation was performed. The hot rolled coil had a weight of 20 tons and an inner diameter of 30 inches. The plate thickness variation value is a plate thickness variation value (maximum plate thickness-minimum plate thickness) after cold rolling of the hot rolled coil outer winding side 20 to 50 m portion. For cold rolling, a tandem cold rolling mill in which five rolling mills were continuously arranged was used. Moreover, after the said cold-rolled steel plate was finish-annealed at a soaking temperature of 1000 ° C., an insulating coating was formed to obtain a final product plate (non-oriented electrical steel plate).

  The hot-rolled steel sheet has C: 0.003 mass%, Si: 1.6 mass%, Mn: 0.4 mass%, sol. Al: 0.0021 mass%, P: 0.12 mass%, S: 0.002 mass%, N: 0.002 mass%, the remainder is melted steel having a component composition consisting of Fe and inevitable impurities, The slab was obtained by continuous casting, and then the slab was reheated to a temperature of 1050 to 1130 ° C. and then hot-rolled.

The magnetic properties were obtained by cutting an Epstein test piece from the rolling direction (L) and the perpendicular direction (C) of the final product plate to obtain magnetic flux density B ₅₀ (magnetic flux density at a magnetizing force of 5000 A / m) and iron loss W _{15 / 50} (iron loss when excited at a magnetic flux density of 1.5 T and a frequency of 50 Hz) was measured and evaluated according to JIS C2552.

As shown in Table 1, in Examples 1 to 18 of the present invention, fluctuations in the plate thickness could be suppressed under conditions where the hot-rolled steel sheet was wound at a high temperature of 550 ° C or higher. Moreover, the steel plate (non-oriented electrical steel plate) with favorable iron loss _{W15 / 50} and magnetic flux density _B50 of the final product board was able to be manufactured. At a winding temperature of 550 ° C., a slight deterioration in magnetic properties was observed compared to a winding temperature of 600 ° C. At a lower coiling temperature of 500 ° C., the plate thickness variation was small, but recrystallization during hot rolling coil storage was insufficient and many unrecrystallized grains remained, resulting in poor appearance and significant magnetic deterioration (Comparative Example). 1). Further, under the condition that the opening ratio of the coil mount was reduced, a slight thickness variation was observed in the steel plate width direction.

  As a comparative example, after the coil was wound at a high temperature, a large plate thickness variation exceeding 10 μm occurred under the condition that the coil did not fall (Comparative Examples 2 to 5).

  Here, as an example of the invention, only Si and Al in the above-described steel component composition were changed to Si: 1.0 mass%, sol. Al: 0.5 mass% (Example 19 of the present invention), Si and Al alone were added to Si: 1.0 mass%, sol. Al: 1.5 mass% (Invention Example 20), Si only Si: 2.0 mass% (Invention Example 21), Si only Si: 2.5 mass% (Invention) As for Example 22), after winding in a coil shape under the same conditions as Example 5 of the present invention and placing and storing it as a coil, cold rolling was performed. It was good.

  In the steel composition, only Si with Si: 5.2 mass% (Comparative Example 6) and P only with P: 0.22 mass% (Comparative Example 7) are the same as in Invention Example 5. After winding in the shape of a coil under the conditions of the above and placing and storing as a coil, when cold rolling, cracks occurred during cold rolling, so the subsequent process was stopped, and the final product plate was manufactured could not. Moreover, since only Mn was Mn: 0.03% (Comparative Example 8), cracks were generated during hot rolling, so the subsequent steps were stopped and the final product plate could not be produced. Moreover, only Al is sol. Al: 0.0060 mass% (Comparative Example 9), S alone S: 0.012 mass% (Comparative Example 10), and Si and Al alone were Si: 1.0 mass%, sol. For Al (2.5% by mass) (Comparative Example 11), it was large when cold-rolled after being wound in the shape of a coil under the same conditions as in Example 5 and placed and stored as a coil. Although the plate thickness variation did not occur, the magnetic properties of the final product plate were greatly deteriorated.

  In the above examples, for relative comparison, the plate thickness, the plate width, the finish annealing temperature and the like were carried out under certain conditions, but the present invention is not limited to this, and other plate thicknesses, plate widths, It is also applied to coil weight, annealing temperature, and the like.

DESCRIPTION OF SYMBOLS 10 Coil 20 Coil overturn apparatus 30 Coil mount 40 Arbitrary structures

Claims (5)

C: 0.01 mass% or less, Si: 5.0 mass% or less, Mn: 0.05 to 3.0 mass%, sol. Al: 0.0050 mass% or less or 0.2 to 2.0 mass%, P: 0.20 mass% or less, S: 0.010 mass% or less and N: 0.010 mass% or less, with the balance being Fe and inevitable After hot-rolling steel having a component composition consisting of mechanical impurities into a coiled coil at a temperature of 600 ° C. or higher, the coil wound up in 30 minutes after the winding is completed A method for manufacturing a hot rolled coil, wherein the hot rolled coil is placed in an end state.
However, in the component composition, when Si is 1.5 mass% or more, sol. Al is 0.0050 mass% or less, and when Si is less than 1.5 mass%, sol. Al is 0.2 to 2.0 mass%. The method for producing a hot-rolled coil according to claim 1, wherein the mounting in the up-end state is continued until the surface temperature of the outer periphery of the coil becomes 300 ° C or lower.   The method for manufacturing a hot-rolled coil according to claim 1 or 2, wherein the coil is overturned so that positions of upper and lower side surfaces of the coil placed in the up-end state are switched.   The method for producing a hot-rolled coil according to any one of claims 1 to 3, wherein the coil is placed on a table having an aperture ratio of 0.3 or more.   Manufacturing the non-oriented electrical steel sheet characterized by cold-rolling and annealing the steel strip paid out from the hot-rolling coil obtained by the manufacturing method of the hot-rolling coil in any one of Claims 1-4 Method.

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