JP5825494B2 - Non-oriented electrical steel sheet and manufacturing method thereof - Google Patents

Description

  The present invention relates to a non-oriented electrical steel sheet and a method for manufacturing the same, and more specifically to a non-oriented electrical steel sheet excellent in both magnetic flux density and iron loss characteristics in a high frequency region and a method for manufacturing the same.

  In recent years, due to demands for global warming countermeasures and energy conservation, in the automotive field, hybrid electric vehicles (HEV) that use both an engine and a motor, electric vehicles (EV) that are driven only by an electric motor, and fuel cell vehicles (FCEV), etc. Development is underway. The driving frequency of these automobile rotating machines tends to increase year by year, and at present, the basic frequency is generally several hundred to several kHz. In addition, since harmonic components are superimposed, the core loss characteristics of the iron core in the frequency range of 1 to 10 kHz have come to be regarded as important in order to increase the efficiency of the motor. In addition, a micro motor used for a drive motor of a hard disk drive is also driven to rotate at high speed (up to several tens of thousands rpm), and it is important to reduce iron loss in a high frequency region of an iron core.

  In order to meet the above requirements, conventionally, an iron element in a high frequency region has been reduced by adding an alloy element such as Si or Al or reducing a plate thickness. However, the addition of the alloy element causes a decrease in the saturation magnetic flux density, and the reduction of the plate thickness needs to increase the cold rolling reduction ratio. As the cold rolling reduction increases, the crystal orientation accumulates in the rolling stable orientation, so that the primary recrystallization texture accumulates in the {111} orientation, leading to a decrease in magnetic flux density. Therefore, even with these methods alone, a reduction in magnetic flux density is inevitable even if iron loss reduction in a high frequency range can be achieved. In addition, a decrease in magnetic flux density leads to an increase in motor copper loss, leading to a decrease in motor efficiency. Therefore, in addition to reducing the iron loss in the high frequency region of the core material, it is considered that increasing the magnetic flux density is also important.

  As can be seen from the above, if a non-oriented electrical steel sheet having a high magnetic flux density and a low iron loss in a high frequency region can be developed, it is considered that it can greatly contribute to the improvement of the efficiency of electrical equipment. As a technique for producing a non-oriented electrical steel sheet having a low iron loss in a high frequency range, for example, Patent Document 1 contains Si: 2.5 to 10 mass%, and C and N are reduced to 100 massppm or less in total. A method of achieving low iron loss in a high frequency region by adding 1.5 to 20 mass% of Cr to the obtained steel and increasing the specific resistance of the steel is disclosed.

JP-A-11-343544

  However, since Cr is an element that lowers the saturation magnetic flux density, it is difficult to achieve both high magnetic flux density and low iron loss in a high frequency range. I have not been able to respond.

  The present invention has been made in view of the above-mentioned problems of the prior art, and its purpose is to provide a non-oriented electrical steel sheet that achieves a high magnetic flux density with low iron loss even in a high frequency range. It is to propose an advantageous manufacturing method.

  The inventors have intensively studied to solve the above problems. As a result, by reducing the Al content and adding P and Ca, the steel sheet is under a higher pressure than the conventional cold rolling reduction ratio, and the heating rate during finish annealing is higher than that of the conventional steel. The inventors have found that the magnetic properties are remarkably improved as compared with conventional materials, and have developed the present invention.

That is, the present invention is C: 0.005 mass% or less, Si: 2 to 4 mass%, Mn: 0.03 to 3 mass%, P: 0.03 to 0.2 mass%, S: 0.005 mass% or less, Al : 0.01 mass% or less and N: 0.005 mass% or less, and further Ca is an atomic ratio with respect to S ((Ca (mass%) / 40) / (S (mass%) / 32)). contained in the range of 5 to 3.5, it has a component composition and the balance being Fe and unavoidable impurities, in plate thickness 0.10～0.20Mm, the magnetic flux density _{B 50} is 1.70T or more and, It is a non-oriented electrical steel sheet having an iron loss W _10/400 of 12 W / kg or less.

  The non-oriented electrical steel sheet of the present invention is characterized by further containing one or two selected from Sn and Sb in the range of 0.003 to 0.5 mass% in addition to the above component composition. To do.

In addition, the present invention, after hot-rolling a steel slab having any of the above-described component compositions, cold-rolled with a cold rolling reduction ratio of 85% or more to obtain a cold-rolled sheet having a final thickness, and finish annealing. In the manufacturing method of the non-oriented electrical steel sheet to be applied, the final thickness of the cold-rolled sheet is set to 0.10 to 0.20 mm, and rapid heating is performed at an average heating rate of 100 ° C./s or higher up to 740 ° C. in the finish annealing. Thus, a method for producing a non-oriented electrical steel sheet is proposed, in which the magnetic flux density B ₅₀ is 1.70 T or more and the iron loss W _10/400 is 12 W / kg or less.

  According to the present invention, a non-oriented electrical steel sheet having excellent magnetic properties can be provided, so that not only a drive motor for a hybrid vehicle or the like, but also a small motor and a small transformer used in various electric devices, etc. Greatly contributes to higher efficiency.

It is a graph showing the effect of cold rolling reduction ratio on the magnetic flux density B _50. It is a graph which shows the influence of the cold rolling reduction ratio which has on the iron loss W _10/400 . It is a graph showing the effect of P content on the magnetic flux density B _50. It is a graph which shows the influence of P content which _gives to iron loss W _10/400 . It is a graph showing the effect of atomic ratio Ca / S on the magnetic flux density _{B 50.} It is a graph which shows the influence of atomic ratio Ca / S which has on iron loss _W10 / ₄₀₀ . It is a graph showing the effect of Al content on the magnetic flux density B _50. It is a graph which shows the influence of Al content which _gives to iron loss _{W10 / 400} . Is a graph showing the effect of heating rate of up to 740 ° C. on the magnetic flux density B _50. It is a graph which shows the influence of the temperature increase rate to 740 _{degreeC which} has on iron loss _{W10 / 400} .

First, an experiment that triggered the development of the present invention will be described.
In order to investigate the influence of the cold rolling reduction ratio on the magnetic properties, C: 0.0025 mass%, Si: 3.5 mass%, Mn: 0.10 mass%, P: 0.05 mass%, S: 0.0020 mass%, A steel slab containing Al: 0.001 mass%, N: 0.0024 mass% and Ca: 0.0025 mass% was heated at 1100 ° C. for 30 minutes, and then hot-rolled to obtain a plate thickness of 0.8 to 2.6 mm. After forming a hot-rolled sheet in the range, annealing at 1000 ° C. for 30 seconds, and then forming a cold-rolled sheet having a thickness of 0.15 mm (reduction ratio: 81 to 94%) by one cold rolling In a direct electric heating furnace, the heating rate was increased to 740 ° C. by changing the heating rate to two levels of 30 ° C./s and 300 ° C./s, and further heated to 950 ° C. at 30 ° C./s and held for 10 seconds. After cooling and cold-rolled annealed plate did.

From the cold-rolled annealed plate thus obtained, an L direction sample of L: 180 mm × C: 30 mm and a C direction sample of L: 30 mm × C: 180 mm were cut out, and the magnetic flux density at a magnetic field strength of 5000 A / m was measured by an Epstein test. The iron loss (W _10/400 ) when excited at (B ₅₀ ), a frequency of 400 Hz, and a magnetic flux density of 1.0 _T was measured, and the results are shown in FIGS.

From FIG. 1 and FIG. 2, it can be seen that the steel sheet heated at a heating rate of 30 ° C./s has inferior magnetic properties as the cold rolling reduction ratio increases. This is considered to be because the degree of integration in the {111} orientation, which is the hard axis of magnetization, increases as the cold rolling reduction ratio increases.
On the other hand, in the steel plate heated at a heating rate of 300 ° C./s, the magnetic properties are improved as the cold rolling reduction ratio increases. Although the cause of this is not yet fully clarified, the inventors consider as follows.

  When P and Ca are added, the {100} <012> orientation and {411} <148> orientation, which are easy axes of magnetization, increase. On the other hand, when the cold rolling reduction is increased, {111} oriented grains, which are hard axes of magnetization, develop, but by increasing the heating rate, the development of {111} orientation is suppressed. Therefore, immediately after the temperature rise, the {100} <012> orientation, which is the easy axis, and the {411} <148> orientation, and the {111} orientation, which is the hard axis, are present in a good balance. Sometimes grains with {100} <012> orientation or {411} <148> orientation phagocytos {111} grains and preferentially grow to improve magnetic properties.

Next, in order to investigate the influence of the P content on the magnetic properties, C: 0.0028 mass%, Si: 3.6 mass%, Mn: 0.10 mass%, S: 0.0020 mass%, Al: 0.003 mass. %, N: 0.0024 mass%, and Ca: 0.0025 mass% A steel slab in which P is variously changed in the range of 0.01 to 0.5 mass% and contained at 1100 ° C. for 30 minutes. After heating, the steel sheet is hot-rolled to obtain a hot-rolled sheet having a thickness of 1.8 mm, subjected to hot-rolled sheet annealing at 1000 ° C. for 30 seconds, and then cold-rolled once to a thickness of 0.15 mm (reduction rate) : 91.7%), and then heated in a direct current heating furnace with the temperature rising rate up to 740 ° C. changed to two levels of 30 ° C./s and 250 ° C./s, s to 950 ° C for 10 seconds After holding for a while, it was cooled to obtain a cold-rolled annealed plate. In addition, since the steel sheets with the addition amount of P of 0.35 mass% and 0.5 mass% were broken during cold rolling, only steel sheets with P: 0.20 mass% or less were cold-rolled annealed plates, and the same as in the experiment described above. The magnetic properties (magnetic flux density B ₅₀ , iron loss W _10/400 ) were measured by the Epstein test, and the results are shown in FIGS. 3 and 4.

  From FIG. 3 and FIG. 4 above, it can be seen that good magnetic properties are obtained when the P content is 0.03 mass% or more at any temperature increase rate of 30 ° C./s and 250 ° C./s. As described above, it is considered that the addition of P increases the {100} <012> orientation and {411} <148> orientation, which are easy magnetization axes, and improves the magnetic characteristics.

Next, in order to investigate the influence of Ca on magnetic characteristics, C: 0.0023 mass%, Si: 3.4 mass%, Mn: 0.50 mass%, P: 0.08 mass%, S: 0.0024 mass% Steel slab containing Ca: 0.0001 to 0.015 mass% in various amounts in a component system containing Al: 0.004 mass% and N: 0.0022 mass% at 1080 ° C. for 30 minutes After heating, it is hot-rolled to obtain a hot-rolled sheet having a thickness of 1.6 mm, subjected to hot-rolled sheet annealing at 1000 ° C. for 30 seconds, and then cold-rolled once to a thickness of 0.15 mm (reduction ratio: 90.6%), and then heated in a direct current heating furnace at a heating rate of up to 740 ° C. at two levels of 30 ° C./s and 300 ° C./s. To 940 ° C. and 10 After holding for 2 seconds, it was cooled to form a cold-rolled annealed plate, and the magnetic properties (magnetic flux density B ₅₀ , iron loss W _10/400 ) were measured by the Epstein test in the same manner as the above-described experiment, and the results are shown in FIG. This is shown in FIG.

  From the above FIG. 5 and FIG. 6, at any heating rate of 30 ° C./s and 300 ° C./s, ((Ca (mass%) / 40) / (S (mass%) / 32), that is, S It can be seen that good magnetic properties are obtained when the atomic ratio of Ca to Ca is in the range of 0.5 to 3.5 because Ca fixes S in steel and precipitates as CaS. In order to improve grain growth during sheet annealing and coarsen the grain size before cold rolling, as the recrystallized texture after cold rolling, the {111} <112> orientation, which is the hard axis of magnetization, decreases. However, if (Ca / 40) / (S / 32) is less than 0.5, the effect is small, while (Ca / 40) / (S / 32) is 3 If it exceeds .5, the precipitation amount of CaS becomes excessive, grain growth is inhibited, and iron loss increases. Presumably because. The results, Ca can be said to be effective to add a range of 0.5 to 3.5 in (Ca / 40) / (S / 32).

Next, in order to investigate the influence of Al on the magnetic properties, C: 0.0025 mass%, Si: 3.2 mass%, Mn: 0.50 mass%, P: 0.08 mass%, N: 0.0022 mass%, A steel slab in which Al is variously changed in a range of 0.001 to 1.0 mass% in a component system containing S: 0.0024 mass%, N: 0.0022 mass%, and Ca: 0.0025 mass%. After heating at 1080 ° C. for 30 minutes, it is hot-rolled to obtain a hot-rolled sheet having a thickness of 1.6 mm, subjected to hot-rolled sheet annealing at 1000 ° C. for 30 seconds, and then cold-rolled once to obtain a thickness of 0 After making a cold-rolled sheet of .15 mm (rolling rate: 90.6%), the heating rate was changed to two levels of 30 ° C./s and 300 ° C./s in a direct current heating furnace, and heated. Furthermore, 9 at 30 ° C./s Heat to 40 ° C., hold for 10 seconds, then cool to cold-rolled annealed plate, and measure magnetic properties (magnetic flux density B ₅₀ , iron loss W _10/400 ) by Epstein test in the same way as the experiment described above. The results are shown in FIG. 7 and FIG.

From FIG. 7 above, the magnetic flux density is improved within a range where the Al content is 0.01 mass% or less at any rate of temperature increase of 30 ° C./s and 300 ° C./s. It can be seen that there is a large margin for improvement at the heating rate. The reason why the magnetic flux density after finish annealing with rapid heating is greatly improved by reducing Al is not yet clear, but by reducing Al, the difference in mobility of grain boundaries due to the grain boundary misorientation angle. As a result, during finish annealing with rapid heating, the {100} <012> orientation and {411} <148> orientation, which are easy axes of magnetization, preferentially grow in a form that engulf the {111} orientation. It is considered a thing.
The iron loss when Al is reduced tends to increase slightly as can be seen from FIG. This is presumably because the effect of rapid heating was offset because Al, which has the effect of improving the iron loss by increasing the specific resistance of steel, was reduced.

Next, in order to investigate the influence of the heating rate on the magnetic properties, C: 0.0025 mass%, Si: 3.3 mass%, Mn: 0.20 mass%, P: 0.10 mass%, S: 0.0020 mass. %, Al: 0.001 mass%, N: 0.0025 mass% and Ca: 0.0030 mass% Steel slab is heated at 1100 ° C for 30 minutes and then hot-rolled to a thickness of 1.6 mm After subjecting to hot-rolled sheet annealing at 980 ° C. for 30 seconds and then forming a cold-rolled sheet having a sheet thickness of 0.15 mm (reduction ratio: 90.6%) by one cold rolling, In the direct electric heating furnace, the heating rate was varied in the range of 30 to 300 ° C./s in a range of 30 to 300 ° C./s, and then heated to 960 ° C. at 30 ° C./s and held for 10 seconds. Cool to cold rolled annealed plate, front Similarly to the experiment described above, magnetic properties (magnetic flux density B ₅₀ , iron loss W _10/400 ) were measured by the Epstein test, and the results are shown in FIGS.

From FIG. 9 and FIG. 10 above, it can be seen that good magnetic properties are obtained by heating at a temperature increase rate of up to 740 ° C. at 100 ° C./s or more and then performing finish annealing. This is because the recrystallization of {111} grains is suppressed by increasing the temperature rising rate, the recrystallization of {110} grains and {100} grains is promoted, and the orientation of the easy axis of magnetization is relatively increased. It is thought that the magnetic properties were improved after rapid heating and finish annealing. From the above, it can be said that the rate of temperature rise is desirably 100 ° C./s or more.
The present invention has been made based on the above experimental results.

Next, the component composition of the non-oriented electrical steel sheet (product) of the present invention will be described.
C: 0.005 mass% or less If C is contained in the product steel plate in an amount exceeding 0.005 mass%, magnetic aging is caused to deteriorate the iron loss characteristics, so the upper limit is made 0.005 mass%. Preferably it is 0.003 mass% or less.

Si: 2 to 4 mass%
Si is an element effective in increasing the specific resistance of steel and reducing iron loss. In order to obtain such an effect, addition of 2 mass% or more is necessary. On the other hand, if added over 4 mass%, the magnetic flux density decreases or it becomes difficult to produce by rolling, so the upper limit is made 4 mass%.

Mn: 0.03 to 3 mass%
Mn is an element necessary for improving hot workability, but if it is less than 0.03 mass%, a sufficient effect cannot be obtained. On the other hand, addition of more than 3 mass% leads to an increase in raw material cost. The range is 0.03 to 3 mass%. Preferably it is the range of 0.05-2 mass%.

P: 0.03-0.2 mass
P is an element effective in increasing the specific resistance of steel and reducing iron loss, and increases the {100} <012> orientation and {411} <148> orientation, which are easy magnetization axes, to increase magnetic properties. Is an element that improves. Such an effect can be obtained by adding 0.03 mass% or more, as can be seen from FIGS. 3 and 4 described above. On the other hand, if added over 0.2 mass%, the steel becomes hard and difficult to roll, so the upper limit is made 0.2 mass%. Preferably it is the range of 0.04-0.1 mass%.

S: 0.005 mass% or less S is an impurity element which is inevitably mixed in. If it exceeds 0.005 mass%, it forms a sulfide-based precipitate and inhibits grain growth during strain relief annealing. Since the magnetic properties are deteriorated, the upper limit is set to 0.005 mass%. Preferably it is 0.004 mass% or less.

Al: 0.01 mass% or less Al, like Si, is an element effective for increasing the specific resistance of steel and reducing iron loss, but in the present invention, it is limited to 0.01 mass% or less. This is because, as can be seen from FIG. 7 and FIG. 8, the magnetic characteristics (magnetic flux density) after finish annealing accompanied by rapid heating is improved by reducing Al.

N: 0.005 mass% or less N is an impurity element that is inevitably mixed. When N exceeds 0.005 mass%, a nitride-based precipitate is formed, and grain growth during strain relief annealing is inhibited. Therefore, the upper limit is set to 0.005 mass%. Preferably it is 0.004 mass% or less.

(Ca (mass%) / 40) / (S (mass%) / 32): 0.5 to 3.5
Ca has the effect of fixing S in steel and precipitating as CaS to improve grain growth during hot-rolled sheet annealing, coarsening the grain size before cold rolling, and improving magnetic properties. In order to obtain such an effect, it is necessary to add (Ca / 40) / (S / 32), that is, an atomic ratio of Ca to S of 0.5 or more. On the other hand, if it is added in excess of 3.5 at (Ca / 40) / (S / 32), the amount of precipitated CaS becomes excessive, and the iron loss increases. Therefore, Ca is (Ca / 40) / (S / 32) in the range of 0.5 to 3.5. Preferably it is the range of 0.5-3.0.

The non-oriented electrical steel sheet of the present invention can appropriately contain the following components in addition to the essential components.
Sn, Sb: 0.003 to 0.5 mass% respectively
Sn and Sb not only improve the texture by improving the texture, but also various effects of preventing the deterioration of magnetic properties by suppressing the oxidation and nitridation of the steel sheet surface layer and the accompanying generation of surface fine grains. It is an element that has an effect. In order to acquire such an effect, it is preferable to add 0.003 mass% or more of any one or more of Sn and Sb. On the other hand, if added over 0.5 mass%, on the contrary, the growth of crystal grains may be hindered, leading to a decrease in magnetic properties. Therefore, it is preferable to add Sn and Sb in the range of 0.003 to 0.5 mass%, respectively.

  In the non-oriented electrical steel sheet of the present invention, the balance other than the above components is Fe and inevitable impurities. However, as long as the effects of the present invention are not impaired, the inclusion of other elements is not rejected.

Next, the thickness of the non-oriented electrical steel sheet of the present invention will be described.
As described above, reducing the thickness of the steel sheet is effective for reducing iron loss in a high frequency region, particularly for reducing eddy current loss. However, when the plate thickness is less than 0.1 mm, not only cold rolling becomes difficult, but also the number of laminated steel plates is increased at the time of assembling the rotor and stator of the motor, and the production efficiency is lowered. On the other hand, if the plate thickness exceeds 0.2 mm, it leads to an increase in iron loss accompanying an increase in eddy current loss. Therefore, in this invention, plate | board thickness shall be the range of 0.1-0.2 mm.

Next, the manufacturing method of the non-oriented electrical steel sheet of this invention is demonstrated.
The method for producing a non-oriented electrical steel sheet according to the present invention first involves melting a steel having the above-mentioned composition suitable for the present invention in a normal refining process using a converter, an electric furnace, a vacuum degassing apparatus, etc. A steel slab is formed by a continuous casting method or an ingot-bundling rolling method.

  Next, the steel slab is hot-rolled by a normal method to form a hot-rolled sheet, and then subjected to hot-rolled sheet annealing as necessary. Although this hot-rolled sheet annealing is not an essential step in the present invention, it is preferably employed as appropriate because it is effective in improving magnetic properties. The annealing temperature when hot-rolled sheet annealing is performed is preferably in the range of 750 to 1050 ° C. If the annealing temperature is less than 750 ° C., an unrecrystallized structure may remain. On the other hand, if it exceeds 1050 ° C., a great load is applied to the annealing equipment. More preferably, it is the range of 800-1000 degreeC.

  The steel sheet after the hot rolling or after the hot-rolled sheet annealing is then pickled and made into a cold-rolled sheet having a final thickness by one cold rolling. The cold rolling reduction ratio at this time needs to be 85% or more as can be seen from FIGS. 1 and 2 described above. This is because if it is less than 85%, the effect of improving the magnetic properties by rapid heating cannot be obtained sufficiently. Further, in order to increase the cold rolling reduction ratio as described above, it is preferable to obtain the final thickness by one cold rolling. In addition, about other rolling conditions, it may be the same as the manufacturing conditions of a normal non-oriented electrical steel sheet.

Next, the steel sheet after the cold rolling is subjected to recrystallization annealing. This recrystallization annealing is an important step in the present invention. As heating conditions, rapid heating is performed up to the recrystallization temperature range. Specifically, an average temperature increase rate from room temperature to 740 ° C. is set to 100 ° C./s. It is necessary to perform rapid heating as described above.
The end point temperature for rapid heating may be at least 740 ° C., which is the temperature at which recrystallization is completed, or may be a temperature exceeding 740 ° C. However, the higher the end point temperature, the higher the equipment cost and power cost required for heating. In addition, there is no restriction | limiting in particular also about the method of rapid heating at 100 degrees C / s or more, For example, a direct current heating method or an induction heating method etc. can be used suitably.

  The steel plate rapidly recrystallized is then subjected to soaking annealing as appropriate and then cooled to obtain a product plate. In addition, the heating rate until the above soaking, the soaking temperature, the soaking time and the subsequent cooling conditions may be performed in accordance with the conditions performed in a normal non-oriented electrical steel sheet, although there is no particular limitation, The soaking temperature is preferably in the range of 800 to 1100 ° C. A more preferable soaking temperature is in the range of 900 to 1050 ° C.

  A steel slab having various composition shown in Table 1 was heated for 1080 × 30 minutes, and then hot-rolled to obtain a hot rolled sheet having a thickness of 1.6 to 2.0 mm, and hot rolled at 800 ° C. for 30 seconds. After the sheet annealing, cold-rolled sheets having the thicknesses shown in Table 1 were obtained by one cold rolling. Thereafter, the cold-rolled sheet was heated in a direct current heating furnace while changing the rate of temperature rise and the temperature reached at the same temperature as shown in Table 1, and then at 30 ° C./s, also shown in Table 1. The temperature was raised to a soaking temperature, held for 10 seconds, then cooled to obtain a cold-rolled annealed plate.

From the cold-rolled annealed plate thus obtained, an L direction sample of L: 180 mm × C: 30 mm and a C direction sample of L: 30 mm × C: 180 mm were cut out, and the magnetic flux density at a magnetic field strength of 5000 A / m was measured by an Epstein test. The iron loss (W _10/400 ) when excited at (B ₅₀ ), a frequency of 400 Hz, and a magnetic flux density of 1.0 _T was measured, and the results are shown in Table 1.
From Table 1, all the steel plates manufactured satisfying the conditions of the present invention have excellent magnetic properties in which the magnetic flux density B ₅₀ is 1.70 T or more and the iron loss W _10/400 is 12 W / kg or less. I understand that.

Claims (3)

C: 0.005 mass% or less, Si: 2 to 4 mass%, Mn: 0.03 to 3 mass%, P: 0.03 to 0.2 mass%, S: 0.005 mass% or less, Al: 0.01 mass% or less And N: 0.005 mass% or less, and further Ca to an atomic ratio to S ((Ca (mass%) / 40) / (S (mass%) / 32)) of 0.5 to 3.5 In the range, the balance is composed of Fe and inevitable impurities, the plate thickness is 0.10 to 0.20 mm, the magnetic flux density B ₅₀ is 1.70 T or more, and the iron loss W _10/400 Is a non-oriented electrical steel sheet having 12 W / kg or less. In addition to the said component composition, it further contains 1 type or 2 types chosen from Sn and Sb in the range of 0.003-0.5 mass%, respectively, The non-directional property of Claim 1 characterized by the above-mentioned. Electrical steel sheet. The steel slab having the component composition according to claim 1 or 2 is hot-rolled, then cold-rolled with a cold rolling reduction ratio of 85% or more to obtain a cold-rolled sheet having a final thickness, and subjected to finish annealing. In the manufacturing method of electrical steel sheet,
The final plate thickness of the cold-rolled plate is 0.10 to 0.20 mm,
By rapidly heating up to 740 ° C. in the finish annealing at an average rate of temperature increase of 100 ° C./s or more,
A method for producing a non-oriented electrical steel sheet, wherein the magnetic flux density B ₅₀ is 1.70 T or more and the iron loss W _10/400 is 12 W / kg or less.

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