KR20190047468A - Non-oriented electrical steel sheet and manufacturing method of the same - Google Patents

Abstract

The present invention provides a non-oriented electrical steel sheet which can be manufactured at low costs, and a manufacturing method thereof. The non-oriented electrical steel sheet comprises 3-4 wt% of Si, 1.5 wt% or lower (excluding 0 wt%) of Al, 1.5 wt% or lower (excluding 0 wt%) of Mn, 0.01 wt% or lower (excluding 0 wt%) of one or more among As and Se, 0.005-0.015 wt% of C, 0.005-0.0015 wt% of N, and the remainder consisting Fe and inevitable impurities, and satisfies the following formulas 1 and 2. The formula 1 is 0.010 <= ([C]+[N]) <= 0.025, and the formula 2 is {0.3×([C]+[N])} <= ([As]+[Se]) <= 0.010, wherein [C], [N], [As] and [Se] in the formula 1 and 2 represent the content (wt%) of C, N, As and Se, respectively.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a non-oriented electrical steel sheet,

A non-oriented electrical steel sheet and a manufacturing method thereof. More specifically, the present invention relates to a non-oriented electrical steel sheet excellent in magnetic properties and capable of being manufactured at low cost, and a method of manufacturing the same.

In recent years, the demand for improving the quality of the non-oriented electrical steel sheet as an electric steel sheet for a small-sized rotor has become stronger from the viewpoint of energy saving. Research and development is also under way in steel companies.

The non-oriented electrical steel sheet is mainly used for a motor which converts electric energy into mechanical energy, and in order to exhibit high efficiency, it requires excellent magnetic characteristics of the non-oriented electrical steel sheet. Particularly, in recent years, as eco-friendly technology has attracted attention, it is very important to increase the efficiency of the motor, which accounts for a large portion of the total electric energy consumption, and the demand for the non-oriented electric steel sheet having an excellent magnetic property is also increasing .

The magnetic properties of the nonoriented electrical steel sheet are typically evaluated through iron loss and magnetic flux density. Iron loss means energy loss occurring at a specific magnetic flux density and frequency, and magnetic flux density means the degree of magnetization obtained under a specific magnetic field. The lower the core loss, the more energy efficient motors can be manufactured under the same conditions. The higher the magnetic flux density, the smaller the motor and the less copper hands, so the non-directional electric steel sheet with low iron loss and high magnetic flux density It is important.

A commonly used method for increasing the magnetic properties of a non-oriented electrical steel sheet is to add an alloy element such as silicon (Si). The addition of these alloying elements can increase the resistivity of the steel. The higher the resistivity, the lower the eddy current loss and the lower the total iron loss. On the other hand, as the amount of silicon (Si) added increases, the magnetic flux density becomes dull and the brittleness increases. If the amount is more than a certain amount, cold rolling becomes impossible and commercial production becomes impossible.

Particularly, as the thickness of the electric steel sheet is made thinner, the iron loss can be reduced. The lowering of the rolling property due to the brittleness is a fatal problem. Therefore, addition of silicon (Si) is limited, and aluminum (Al) and manganese (Mn) are added to increase the resistivity of additional steel, thereby producing the highest grade nonoriented electric steel sheet having excellent magnetic properties.

In order to improve the magnetic properties of the non-oriented electrical steel sheet, it is important to reduce the amount of steel impurities. The impurities inevitably incorporated in the steelmaking process precipitate in the form of carbides, nitrides and sulfides in the final product, which interferes with grain growth and magnetic wall movement, thereby deteriorating the magnetic properties of the non-oriented electrical steel sheet.

Therefore, for the production of nonoriented electrical steel sheet, it is essential to clean the steelmaking process to minimize the amount of all impurities, which leads to a decrease in productivity and an increase in the process cost.

In order to improve the cleanliness of non-oriented electric steel plate high-quality materials, refining time and cost have been applied in steelmaking process, and there have been problems such as restrictions.

One embodiment of the present invention provides a non-oriented electrical steel sheet and a method of manufacturing the same. Specifically, there is provided a non-oriented electrical steel sheet excellent in magnetic properties and capable of being manufactured at low cost, and a method of manufacturing the same.

The non-oriented electrical steel sheet according to an embodiment of the present invention may contain 3.0 to 4.0% of Si, 1.5% or less of Al (excluding 0%), 1.5% or less of Mn (excluding 0%), At least one of As and Se: not more than 0.010% (excluding 0%), C: 0.005 to 0.015%, N: 0.005 to 0.0015%, balance Fe and unavoidable impurities, do.

[Formula 1]

0.010? ([C] + [N])? 0.025

[Formula 2]

{0.3 占 ([C] + [N])? ([As] + [Se])? 0.010

(In the formulas 1 and 2, [C], [N], [As] and [Se] represent the content (% by weight) of C, N, As and Se, respectively.

The average grain size of the electrical steel sheet may be 100 to 170 탆.

S: not more than 0.004% (excluding 0%), Cu: not more than 0.03% (excluding 0%), Cr: not more than 0.2% (excluding 0%), Ti: not more than 0.003% ), V: not more than 0.003% (excluding 0%), B: not more than 0.001% (excluding 0%), Zr: not more than 0.003% (excluding 0%) and Mg: not more than 0.005% And the like) may be further included.

The content of As may be 0.0020 to 0.0070%, and the content of Se may be 0.0005 to 0.0050%.

A method of manufacturing a non-oriented electrical steel sheet according to an embodiment of the present invention includes: 3.0 to 4.0% of Si, 1.5% or less of Al (excluding 0%), 1.5% or less of Mn (excluding 0% ), At least one of As and Se: not more than 0.010% (excluding 0%), C: 0.005 to 0.015%, N: 0.005 to 0.0015%, balance Fe and unavoidable impurities, Lt; / RTI &gt; Hot rolling the slab to produce a hot rolled sheet; Cold-rolling the hot-rolled sheet to produce a cold-rolled sheet; And finally annealing the cold-rolled sheet.

[Formula 1]

0.010? ([C] + [N])? 0.025

[Formula 2]

{0.3 占 ([C] + [N])? ([As] + [Se])? 0.010

(C), [N], [As] and [Se] in the formula 1 and the formula 2 indicate the content (% by weight) of C, N, As and Se, respectively.

In the final annealing step, the following formula 3 can be satisfied.

[Formula 3]

0.6? [Ash time] / {([C] + [N]) 占 10000}? 0.7

(C) and [N] are the amounts of C and N, respectively, in [sec] and [N], respectively, (% By weight).

The slab is made up of at most 0.004% of S (excluding 0%), at most 0.03% of Cu (excluding 0%), at most 0.2% of Cr, at most 0.003% of Ti 0.003% or less (excluding 0%), B: 0.001% or less (excluding 0%), Zr: 0.003% or less (excluding 0%), and Mg: 0.005% or less (Exclusive of 0%).

And further comprising the step of annealing the hot-rolled sheet after the step of producing the hot-rolled sheet.

The [ash time] may be 70 to 170 seconds.

The non-oriented electrical steel sheet according to one embodiment of the present invention and the method of manufacturing the same provide a non-oriented electrical steel sheet excellent in magnetic properties even at a sufficiently high content of carbon (C) and nitrogen (N) .

The terms first, second and third, etc. are used to describe various portions, components, regions, layers and / or sections, but are not limited thereto. These terms are only used to distinguish any moiety, element, region, layer or section from another moiety, moiety, region, layer or section. Thus, a first portion, component, region, layer or section described below may be referred to as a second portion, component, region, layer or section without departing from the scope of the present invention.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the invention. The singular forms as used herein include plural forms as long as the phrases do not expressly express the opposite meaning thereto. Means that a particular feature, region, integer, step, operation, element and / or component is specified and that the presence or absence of other features, regions, integers, steps, operations, elements, and / It does not exclude addition.

When referring to a portion as being "on" or "on" another portion, it may be directly on or over another portion, or may involve another portion therebetween. In contrast, when referring to a part being "directly above" another part, no other part is interposed therebetween.

Unless otherwise defined, all terms including technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Commonly used predefined terms are further interpreted as having a meaning consistent with the relevant technical literature and the present disclosure, and are not to be construed as ideal or very formal meanings unless defined otherwise.

Unless otherwise stated,% means% by weight, and 1 ppm is 0.0001% by weight.

In an embodiment of the present invention, the term further includes an additional element, which means that an additional amount of the additional element is substituted for the remaining iron (Fe).

Hereinafter, embodiments of the present invention will be described in detail so that those skilled in the art can easily carry out the present invention. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein.

Non-oriented electrical steel sheet

In one embodiment of the present invention, the content of C, N, As and Se is controlled while optimizing the composition of the non-oriented electrical steel sheet, particularly the range of Si, Al and Mn, Can be provided.

The non-oriented electrical steel sheet according to an embodiment of the present invention may contain 3.0 to 4.0% of Si, 1.5% or less of Al (excluding 0%), 1.5% or less of Mn (excluding 0%), At least one of As and Se: 0.010% or less (excluding 0%), C: 0.005 to 0.015%, N: 0.005 to 0.0015%, the balance Fe and unavoidable impurities.

First, the reasons for limiting the components of the non-oriented electrical steel sheet will be described below.

Si: 3.0 to 4.0 wt%

Silicon (Si) plays a role of lowering the iron loss by increasing the resistivity of the material, and when it is added too little, the effect of improving the iron loss may be insufficient. On the other hand, if too much is added, the brittleness of the material may increase and the rolling productivity may be deteriorated drastically. Therefore, silicon (Si) can be added in the above-mentioned range.

Al: 1.5 wt% or less

Aluminum (Al) serves to lower the iron loss by increasing the resistivity of the material, and when added too little, the effect of improving the iron loss may be insufficient. On the other hand, if it is added too much, excessive nitrides are formed to deteriorate the magnetic properties, and problems may occur in all processes such as steelmaking and continuous casting, resulting in a significant decrease in productivity. Therefore, aluminum (Al) may be added in the range described above. Specifically, it may contain 0.1 to 1.3% by weight of aluminum (Al).

Mn: 1.5% by weight or less

Manganese (Mn) enhances the specific resistance of the material to improve the iron loss and form a sulfide. When too little Mn is added, the effect of improving the iron loss may be insufficient. On the other hand, when added too much, MnS is excessively precipitated and the formation of {111} texture which is disadvantageous to magnetism is promoted, so that the magnetic flux density can be drastically reduced. Therefore, manganese (Mn) can be added in the range described above. Specifically, 0.1 to 1.2% by weight of manganese (Mn) may be contained.

At least one of As and Se: not more than 0.010% by weight

Arsenic (As) and selenium (Se) are trace elements and can play a role in inhibiting carbonitride formation because these elements are segregated at grain boundaries. However, if it is added too much, it may act as an impurity element and degrade magnetism. Therefore, at least one of arsenic (As) and selenium (Se) may be added in the range described above.

Specifically, both arsenic (As) and selenium (Se) may be added. In this case, the sum of arsenic (As) and selenium (Se) is limited to 0.01 wt% or less.

Specifically, the content of arsenic (As) is 0.0020 to 0.0070% by weight, and the content of selenium (Se) is 0.0005 to 0.0050% by weight.

C: 0.005 to 0.015 wt%

Carbon (C) causes self-aging and combines with other impurity elements to generate carbides, thereby lowering the magnetic properties, so the lower the content, the better. If it is less than 0.005% by weight, the process cost is increased for reduction of the element. Due to the addition of arsenic (As) and selenium (Se), up to 0.015 wt% of carbon (C) can be added.

N: 0.005 to 0.015 wt%

Nitrogen (N) not only forms fine and long AlN precipitates in the base material but also forms fine nitrides by bonding with impurity elements to suppress grain growth and deteriorate iron loss, so that the lower the content, the better. If it is less than 0.005% by weight, the process cost is increased for reduction of the element. Nitrogen (N) can be added up to 0.015% by weight due to the addition of arsenic (As) and selenium (Se).

The above-mentioned carbon (C) and nitrogen (N) need to be managed not only individually but in an amount thereof. In one embodiment of the present invention, carbon (C) and nitrogen (N) may satisfy the following formula (1).

[Formula 1]

0.010? ([C] + [N])? 0.025

(In the formula 1, [C] and [N] represent the content (% by weight) of C and N, respectively.)

Carbon (C) and nitrogen (N) form carbides and nitrides to deteriorate the magnetic properties, so that they are preferably as low as possible. If the sum of the carbon (C) and nitrogen (N) contents is less than 0.010 wt%, the process cost increases to reduce the element. On the other hand, if it exceeds 0.025% by weight, the carbonitride is not inhibited and the magnetic properties may be deteriorated.

Carbon (C) and nitrogen (N) described above need to be managed in association with arsenic (As) and selenium (Se). In one embodiment of the present invention, arsenic (As), selenium (Se), carbon (C), and nitrogen (N)

[Formula 2]

{0.3 占 ([C] + [N])? ([As] + [Se])? 0.010

(In the formula 2, [C], [N], [As] and [Se] represent the contents (% by weight) of C, N, As and Se, respectively.

When the sum of the contents of arsenic (As) and selenium (Se) is less than the value obtained by multiplying the sum of the contents of carbon (C) and nitrogen (N) by 0.3, the carbonitride inhibition is not sufficient and the magnetic properties are degraded, .

In addition, the average grain size of the non-oriented electrical steel sheet according to an embodiment of the present invention may be 100 to 170 탆. When the crystal grains are sufficiently grown to have an average grain size within the above-mentioned range, the magnetic properties may be excellent despite the formation of the carbonitride.

The iron loss average value (W _15/50 ) may be _2.1 W / kg or less and the magnetic flux density (B ₅₀ ) may be 1.68 T or more as the magnetic property with controlling the average grain size of 100 to 170 탆. Specifically, the iron loss average value (W _15/50 ) may be 1.9 to _2.1 W / kg, and the magnetic flux density (B ₅₀ ) may be 1.68 to 1.7 T.

Impurity element

In addition to the above elements, impurity elements which are inevitably incorporated such as S, Cu, Cr, Ti, V, B, Zr, and Mg may be included. S: 0.004 wt% or less, Cu: 0.03 wt% or less, Cr: 0.2 wt% or less, Ti: 0.003 wt% or less, V: 0.003 wt% or less Or less, B: 0.001 wt% or less, Zr: 0.003 wt% or less, and Mg: 0.005 wt% or less.

Method for manufacturing non-oriented electrical steel sheet

A method of manufacturing a non-oriented electrical steel sheet according to an embodiment of the present invention includes: 3.0 to 4.0% of Si, 1.5% or less of Al (excluding 0%), 1.5% or less of Mn (excluding 0% ), At least one of As and Se: 0.010% or less (excluding 0%), C: 0.005-0.015%, N: 0.005-0.0015%, the balance Fe and unavoidable impurities, 2, producing a hot-rolled sheet by hot-rolling the slab, cold-rolling the hot-rolled sheet to produce a cold-rolled sheet, and finally annealing the cold-rolled sheet.

After the step of producing the hot-rolled steel sheet, the step of annealing the hot-rolled steel sheet may further include the step of annealing the hot-rolled steel sheet.

Hereinafter, each step will be described in detail.

First heat the slab. The reason why the addition ratio of each composition in the slab is limited is the same as the reason for limiting the composition of the non-oriented electrical steel sheet described above, so repeated description is omitted. The composition of the slab is substantially the same as that of the non-oriented electrical steel sheet because the composition of the slab does not substantially change during the manufacturing process such as hot rolling, hot rolling annealing, cold rolling and final annealing, which will be described later.

Further, since the composition of the slab and the composition of the non-oriented electrical steel sheet are substantially the same, the slab satisfies the above-mentioned formulas 1 and 2. [ The effect of satisfying the equations 1 and 2 will be superseded by the above description.

The slab is charged into a heating furnace and heated to 1100 to 1250 캜. Upon heating at a temperature exceeding 1250 占 폚, the precipitate may be redissolved and may be precipitated finely after hot rolling.

The heated slab is hot-rolled to 2 to 2.3 mm to produce a hot-rolled sheet. In the step of producing the hot rolled plate, the finishing temperature may be 800 to 1000 占 폚.

After the step of producing the hot-rolled steel sheet, the step of annealing the hot-rolled steel sheet may further include the step of annealing the hot-rolled steel sheet. At this time, the hot-rolled sheet annealing temperature may be 850 to 1150 ° C. If the annealing temperature of the hot-rolled sheet is less than 850 캜, the structure does not grow or grows finely and the synergistic effect of the magnetic flux density is small. If the annealing temperature exceeds 1150 캜, the magnetic properties are rather deteriorated. Can be bad.

Specifically, the temperature range may be 950 to 1125 ° C. The hot-rolled sheet annealing is performed in order to increase the orientation favorable to magnetism as required, and may be omitted.

Next, the hot rolled sheet is pickled and cold rolled to a predetermined thickness. The cold-rolled steel sheet may be cold-rolled by applying a reduction ratio of 70 to 95% to a final thickness of 0.2 to 0.65 mm.

The final cold-rolled cold-rolled sheet is subjected to final annealing so as to satisfy the following formula (3). The final annealing temperature may be 750 to 1050 占 폚. If the final annealing temperature is too low, recrystallization may not occur sufficiently, and if the final annealing temperature is too high, rapid growth of crystal grains may occur and magnetic flux density and high frequency iron loss may be caused to heat. In the final annealing process, all of the processing crystals formed in the cold rolling step as the previous step can be recrystallized (i.e., 99% or more).

[Formula 3]

0.6? [Ash time] / {([C] + [N]) 占 10000}? 0.7

([C] and [N] denote the content (% by weight) of C and N, respectively, in the formula (3), [ash time] represents the time of ash deposition at 1000 ° C or higher in the annealing furnace in sec. )

Generally, the ash time means the time from when the cold-rolled sheet is charged into the annealing furnace to when it is extracted. In the present invention, the term "ash time" refers to the time during which the cold-rolled steel sheet exists in the section where the atmospheric temperature is 1000 ° C or higher in the entire time in which the cold-rolled sheet exists in the final annealing furnace.

If the numerical value expressed by [ash time] / {([C] + [N]) x 10000} is less than 0.6, the ash time for grain growth may be insufficient and the magnetism may become dull. On the other hand, if the numerical value expressed by [ash time] / {([C] + [N]) × 10000} exceeds 0.7, the ash time is too long to induce crystallization of the grains.

[As time] may be 70 to 170 seconds.

By satisfying the formula 3, the average grain size of the final annealed steel sheet can be 100 to 170 탆. Despite the formation of carbonitride, the magnetic properties can be excellent. The magnetic properties may have an iron loss average (W _15/50 ) of _2.1 W / kg or less and a magnetic flux density (B ₅₀ ) of 1.68 T or more.

Hereinafter, specific examples of the present invention will be described. However, the following examples are only a concrete example of the present invention, and the present invention is not limited to the following examples.

Example

A slab containing the remainder Fe and unavoidable impurities was prepared as shown in Table 1 below. The slab was heated to 1140 占 폚 and hot-rolled at a finishing temperature of 880 占 폚 to obtain a hot-rolled sheet having a thickness of 2.3 mm. The hot-rolled hot-rolled sheet was subjected to hot-rolled sheet annealing at 1030 ° C for 100 seconds, pickling and cold rolling to a thickness of 0.35 mm and final annealing as shown in Table 2 below.

In Table 2 below shows the [ashes time], average grain diameter, the iron loss (W15 / 50) and magnetic flux density (B _50). The magnetic properties such as iron loss and magnetic flux density were measured with Epstein tester by cutting 30 specimens of width 30mm × length 305mm × 30 pieces for each specimen. In this case, B ₅₀ is a magnetic flux density induced at a magnetic field of _{5000 A} / m, and W _15/50 means an iron loss when a magnetic flux density of 1.5 T is induced at a frequency of 50 Hz.

number Si
(%) Al
(%) Mn
(%) C
(%) N
(%) As + Se
(%) As
(%) Se
(%) division A1 3.0 1.2 0.2 0.0155 0.0052 0.0085 0.0071 0.0014 Comparative Example A2 3.0 1.2 0.2 0.0075 0.017 0.0098 0.0054 0.0044 Comparative Example A3 3.0 1.2 0.2 0.013 0.0135 0.0083 0.0066 0.0017 Comparative Example A4 3.0 1.2 0.2 0.0125 0.0118 0.0058 0.0032 0.0026 Comparative Example A5 3.0 1.2 0.2 0.0118 0.0066 0.0115 0.0074 0.0041 Comparative Example A6 3.0 1.2 0.2 0.0068 0.0058 0.0075 0.0043 0.0032 Example A7 3.0 1.2 0.2 0.0115 0.0123 0.0087 0.0049 0.0038 Example A8 3.0 1.2 0.2 0.0078 0.0097 0.0065 0.0031 0.0034 Example A9 3.0 1.2 0.2 0.0145 0.0103 0.0077 0.0035 0.0042 Example A10 3.0 1.2 0.2 0.0059 0.0145 0.0083 0.0047 0.0036 Example B1 3.2 0.7 0.2 0.0175 0.0072 0.0075 0.0042 0.0033 Comparative Example B2 3.2 0.7 0.2 0.0085 0.0156 0.0077 0.0057 0.0020 Comparative Example B3 3.2 0.7 0.2 0.0145 0.0139 0.0089 0.0053 0.0036 Comparative Example B4 3.2 0.7 0.2 0.0066 0.0056 0.0032 0.0023 0.0009 Comparative Example B5 3.2 0.7 0.2 0.0078 0.0142 0.0104 0.0043 0.0061 Comparative Example B6 3.2 0.7 0.2 0.0143 0.0072 0.0068 0.0047 0.0021 Example B7 3.2 0.7 0.2 0.0056 0.0147 0.0095 0.0054 0.0041 Example B8 3.2 0.7 0.2 0.0098 0.0087 0.0087 0.0064 0.0023 Example B9 3.2 0.7 0.2 0.0102 0.0104 0.0075 0.0066 0.0009 Example B10 3.2 0.7 0.2 0.0129 0.0115 0.0096 0.0051 0.0045 Example C1 3.4 0.7 0.5 0.0169 0.0066 0.0075 0.0043 0.0032 Comparative Example C2 3.4 0.7 0.5 0.0078 0.016 0.0083 0.0033 0.0050 Comparative Example C3 3.4 0.7 0.5 0.0147 0.0129 0.0087 0.0036 0.0051 Comparative Example C4 3.4 0.7 0.5 0.0068 0.0078 0.0035 0.0020 0.0015 Comparative Example C5 3.4 0.7 0.5 0.0128 0.0065 0.0114 0.0022 0.0092 Comparative Example C6 3.4 0.7 0.5 0.0068 0.0137 0.0098 0.0054 0.0044 Example C7 3.4 0.7 0.5 0.0078 0.0145 0.0075 0.0055 0.0020 Example C8 3.4 0.7 0.5 0.0066 0.0052 0.0058 0.0029 0.0029 Example C9 3.4 0.7 0.5 0.0107 0.0069 0.0077 0.0037 0.0040 Example C10 3.4 0.7 0.5 0.0099 0.0059 0.0092 0.0044 0.0048 Example

number [C] + [N]
(%) [Ash time]
(second) [Ash time]
/ {([C] + [N])
× 10000} Grain Size
(탆) B ₅₀
(T) W _15/50
(W / kg) division A1 0.0207 132 0.638 85 1.66 2.30 Comparative Example A2 0.0245 148 0.604 95 1.65 2.27 Comparative Example A3 0.0265 168 0.634 82 1.66 2.29 Comparative Example A4 0.0243 165 0.679 82 1.66 2.29 Comparative Example A5 0.0184 125 0.679 95 1.66 2.28 Comparative Example A6 0.0126 59 0.468 98 1.67 2.11 Example A7 0.0238 187 0.786 177 1.67 2.14 Example A8 0.0175 108 0.617 120 1.68 2.01 Example A9 0.0248 155 0.625 135 1.68 2.04 Example A10 0.0204 141 0.691 159 1.68 2.03 Example B1 0.0247 153 0.619 75 1.65 2.32 Comparative Example B2 0.0241 168 0.697 95 1.66 2.29 Comparative Example B3 0.0284 175 0.616 84 1.65 2.27 Comparative Example B4 0.0122 78 0.639 87 1.66 2.34 Comparative Example B5 0.022 148 0.673 92 1.66 2.29 Comparative Example B6 0.0215 112 0.521 84 1.67 2.12 Example B7 0.0203 168 0.828 185 1.67 2.13 Example B8 0.0185 125 0.676 165 1.68 2.00 Example B9 0.0206 128 0.621 127 1.68 2.01 Example B10 0.0244 168 0.689 168 1.68 2.03 Example C1 0.0235 142 0.604 78 1.66 2.26 Comparative Example C2 0.0238 165 0.693 88 1.66 2.28 Comparative Example C3 0.0276 175 0.634 85 1.65 2.31 Comparative Example C4 0.0146 95 0.651 75 1.66 2.42 Comparative Example C5 0.0193 125 0.648 79 1.66 2.35 Comparative Example C6 0.0205 117 0.571 93 1.67 2.10 Example C7 0.0223 159 0.713 173 1.67 2.13 Example C8 0.0118 76 0.644 125 1.68 1.99 Example C9 0.0176 106 0.602 107 1.68 2.03 Example C10 0.0158 108 0.684 156 1.68 2.00 Example

A2, A3, B1, B2, B3 (C) content or nitrogen (N) content exceeding the range of the present invention or not satisfying the formula (1) , And C1, C2, and C3, the magnetic properties were not excellent.

A5, B4, B5, C4 and C5, which do not satisfy the formula 2 or the sum of the content of arsenic (As) and selenium (Se) exceeds the range of the present invention, the magnetic properties are not excellent.

A3, A4, A5, B1, B2, B3, B4, B5, C1, C2, C3, C4 and C5 in the case of A6, A7, B6, B7, But the average grain size was out of the range of 100 to 170 μm due to the unsatisfactory formula 3. A9, A10, B8, B9, B10, C8, C9 and C10.

A6, A7, A8, A9, A10, B6, B7, B8, B9, B10, C6, C7, C8, C9 and C10, which fall within the scope of the present invention, , A5, B1, B2, B3, B4, B5, C1, C2, C3, C4 and C5.

It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present invention as defined by the following claims and their equivalents. It will be understood that the invention may be embodied in other specific forms without departing from the spirit or scope of the invention. It is therefore to be understood that the embodiments and / or the examples described above are illustrative in all aspects and not restrictive.

Claims (9)

(Excluding 0%), Mn: 1.5% or less (excluding 0%), at least one of As and Se: 0.010% or less (0% or less) 0.005 to 0.015% of N, 0.005 to 0.0015% of N, the balance of Fe and unavoidable impurities, and satisfies the following formulas (1) and (2).
[Formula 1]
0.010? ([C] + [N])? 0.025
[Formula 2]
{0.3 占 ([C] + [N])? ([As] + [Se])? 0.010
(In the formulas 1 and 2, [C], [N], [As] and [Se] represent the content (% by weight) of C, N, As and Se, respectively. The method according to claim 1,
Wherein the average grain size of the electrical steel sheet is 100 to 170 占 퐉. The method according to claim 1,
S: not more than 0.004% (excluding 0%), Cu: not more than 0.03% (excluding 0%), Cr: not more than 0.2% (excluding 0%), Ti: not more than 0.003% ), V: not more than 0.003% (excluding 0%), B: not more than 0.001% (excluding 0%), Zr: not more than 0.003% (excluding 0%) and Mg: not more than 0.005% (Excluding the non-oriented electrical steel sheet). The method according to claim 1,
Wherein the content of As is 0.0020 to 0.0070%, and the content of Se is 0.0005 to 0.0050%. (Excluding 0%), Mn: 1.5% or less (excluding 0%), at least one of As and Se: 0.010% or less (0% or less) 0.005 to 0.015% of C, 0.005 to 0.0015% of N, the balance Fe and unavoidable impurities, and satisfying the following equations (1) and (2):
Hot rolling the slab to produce a hot rolled sheet;
Cold-rolling the hot-rolled sheet to produce a cold-rolled sheet; And
And finally annealing the cold rolled steel sheet.
[Formula 1]
0.010? ([C] + [N])? 0.025
[Formula 2]
{0.3 占 ([C] + [N])? ([As] + [Se])? 0.010
(C), [N], [As] and [Se] in the formula 1 and the formula 2 indicate the content (% by weight) of C, N, As and Se, respectively. 6. The method of claim 5,
In the final annealing step,
Wherein the non-oriented electrical steel sheet satisfies the following formula (3).
[Formula 3]
0.6? [Ash time] / {([C] + [N]) 占 10000}? 0.7
(C) and [N] are the amounts of C and N, respectively, in [sec] and [N], respectively, (% By weight). 6. The method of claim 5,
The slabs
S: not more than 0.004% (excluding 0%), Cu: not more than 0.03% (excluding 0%), Cr: not more than 0.2% (excluding 0%), Ti: not more than 0.003% ), V: not more than 0.003% (excluding 0%), B: not more than 0.001% (excluding 0%), Zr: not more than 0.003% (excluding 0%) and Mg: not more than 0.005% (Excluding the non-oriented electrical steel sheet). 6. The method of claim 5,
After the step of producing the hot rolled sheet,
And annealing the hot-rolled steel sheet for hot-rolled steel sheet. The method according to claim 6,
The [ash time]
70 to 170 seconds.