KR20150062246A - Non-oriented electrical steel sheets and method for manufacturing the same - Google Patents

Abstract

Disclosed are a non-oriented electrical steel sheet and a method for manufacturing the same. The non-oriented electrical steel sheet of the present invention comprises: less than or equal to 0.005 wt% of C (not including 0 wt%); less than or equal to 2 wt% of Si (not including 0 wt%); less than or equal to 0.08 wt% of Mn; 0.02-0.2 wt% of P; 0.001-0.005 wt% of S; less than or equal to 0.005 wt% of Al; less than or equal to 0.005 wt% of N (not including 0 wt%); less than or equal to 0.005 wt% of Ti (not including 0 wt%); 0.03-0.2 wt% of at least one of Sn and Sb; and the rest of Fe and unavoidably added impurities. The Si and the Mn satisfy 0.7 <=([Si]-[Mn])<=1.7.

Description

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

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a non-oriented electrical steel sheet, and more particularly, to a non-oriented electrical steel sheet having an excellent magnetic property by controlling the component system of the steel sheet.

The nonoriented electric steel sheet is used as an iron core material in rotating devices such as motors, generators, and stationary devices such as small transformers, and plays an important role in determining the energy efficiency of electric devices.

The characteristics of the electric steel sheet include iron loss and magnetic flux density. The iron loss is small and the magnetic flux density is high, which is preferable. When the magnetic field is induced by adding electricity to the iron core, the lower the iron loss, And the higher the magnetic flux density, the larger the magnetic field can be induced with the same energy.

In order to reduce iron loss, Si, Al, Mn, etc., which are alloying elements with high resistivity, are added. This method has a problem that the iron loss is reduced but the saturation magnetic flux density is also decreased.

If the amount of Si added is 4% or more, the workability is lowered, which makes cold rolling difficult, resulting in a decrease in productivity and a large amount of Al and Mn. The more the addition is made, the lower the rolling property is, and the hardness is increased and the workability is lowered.

The present invention provides a non-oriented electrical steel sheet having a low iron loss and excellent magnetic properties by optimally controlling components of Si, Mn, Al, P, Sn, and Sb among alloying elements of steel, and a method of manufacturing the same There is a purpose.

The non-oriented electrical steel sheet according to one embodiment of the present invention is characterized by containing, by weight%, C: not more than 0.005% (not including 0%), Si: not more than 2% (not including 0% 0.005% or less (inclusive of 0%) of Ti, 0.005% or less of Ti (inclusive of 0% of Ti), 0.08% or less of P, 0.02 to 0.2% of P, 0.001 to 0.005% ), 0.03 to 0.2% of at least one of Sn and Sb, and the balance contains Fe and other inevitably added impurities,

The Si and the Mn satisfy 0.7? ([Si] - [Mn])? 1.7 where [Si] and [Mn] represent the weight percent (%) of Si and Mn, respectively.

[P] + [Sn] + [Sb]? 0.2 where P, Sn and Sb are the weight percentages of P, Sn and Sb, (%)).

Further, the non-oriented electrical steel sheet may satisfy V _{110}? 0.2 and V _g? 0.08. Where V _{110} is the fraction of {110} texture for the sum of all orientations, V _g Means the fraction of the (110) [001] texture of the sum of all orientations)

The magnetic flux density of the electrical steel sheet is B ₅₀ (L) ≥1.81 T and

B ₅₀ (L) -B ₅₀ (C)? 0.07 T

(Where B ₅₀ (L) is the magnetic flux density in the rolling direction induced by adding a magnetic field of 5000 A / m, and B ₅₀ (C) is the magnetic flux density in the direction perpendicular to the rolling direction)

Can be satisfied.

Wherein the contents of Cu, Ni and Cr are added in an amount of 0.05 wt% or less, respectively, and the content of Zr, Mo and V is 0.01% by weight or less

The size of the crystal grains in the microstructure of the electrical steel sheet may be 20 to 120 mu m.

A method of manufacturing a non-oriented electrical steel sheet according to an embodiment of the present invention includes:

C: not more than 0.005% (not including 0%), Si: not more than 2% (not including 0%), Mn: not more than 0.08%, P: 0.001 to 0.005% of Al, 0.005% or less of N, 0.005% or less of N (not including 0%), 0.005% or less of Ti (not including 0%), 0.03 to 0.2% And the remainder comprises Fe and other inevitably added impurities, wherein Si and Mn satisfy 0.7? ([Si] - [Mn])? 1.7 where [Si] and [Mn] % &Lt; / RTI &gt;(%)); Heating the slab to 1,200 ° C or less and then rolling to produce a hot-rolled steel sheet; Pickling the hot-rolled steel sheet and rolling it to 0.10 to 0.70 mm to produce a cold-rolled steel sheet; And finishing annealing the cold-rolled steel sheet at 850 to 1,100 ° C.

P, Sn, and Sb satisfy the relation of 0.05? ([P] + [Sn] + [Sb])? 0.2 where [P], [Sn], [Sb] )) Can be satisfied.

In the step of manufacturing the hot-rolled steel sheet,

The finish rolling may be characterized in that it finishes in a ferrite single phase region of {A ₁ temperature (° C) - 40 ° C} or lower.

The hot-rolled steel sheet may further include a step of annealing the hot-rolled steel sheet at 1,000 to 1,200 ° C, and the hot-rolled sheet annealing may be performed in a single-phase austenite region of A ₃ temperature or more.

The electric steel sheet having completed the finish annealing can satisfy V _{110}? 0.2 and V _g? 0.08. (Where V _{110} represents the fraction of {110} texture)

The magnetic flux density of the electric steel sheet after completion of the finish annealing is B ₅₀ (L) ≥1.81 T and B ₅₀ (L) -B ₅₀ (C) ≥0.07 T (where B ₅₀ (L) , The magnetic flux density in the rolling direction derived from the B ₅₀ (C) means the magnetic flux density in the width direction perpendicular to the B ₅₀ (C) rolling direction).

Wherein the contents of Cu, Ni and Cr are added in an amount of 0.05 wt% or less, respectively, and the content of Zr, Mo and V is 0.01% by weight or less.

The size of the crystal grains in the microstructure of the electric steel sheet after finishing annealing may be 20 to 120 탆.

The non-oriented electrical steel sheet according to the present invention can produce a non-oriented electrical steel sheet having an excellent iron loss reduction ratio and improved magnetism remarkably by controlling the component system of Si, Mn, Al, P, Sn and Sb optimally.

Further, the non-oriented electrical steel sheet according to the present invention can be controlled in the range of 0.7? ([Si] - [Mn])? 1.7 so as to undergo a phase transformation during the heat treatment process, thereby improving the magnetism by increasing the texture favorable to magnetism.

In addition, the non-oriented electrical steel sheet according to the present invention the finish rolling - and not to be carried {A ₁ temperature (℃) 40 ℃} in the ferrite single-phase region hereinafter, the hot-rolled sheet annealing is magnetic by carrying out in the austenite single-phase region or more A ₃ temperature It is possible to improve the magnetism by increasing the favorable aggregate structure.

The addition amount of Si is 2 wt% or less, the amount of Mn is 0.08 wt% or less, and the amount of Al is added to 0.005 wt% or less, thereby minimizing the addition amount of the alloying element and optimizing the component system of the alloy element A non-oriented electrical steel sheet excellent in magnetic flux density and improved in iron loss, and a method of manufacturing the same.

In addition, the non-oriented electrical steel sheet produced by the present invention has excellent magnetic properties, so that it is possible to omit additional processes such as decarburization annealing for improving magnetic properties, thereby improving the economical efficiency.

BRIEF DESCRIPTION OF THE DRAWINGS The advantages and features of the present invention and the manner of achieving them will become apparent with reference to the embodiments described in detail below with reference to the accompanying drawings. However, it is to be understood that the present invention is not limited to the disclosed embodiments, but may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. It is intended that the disclosure of the present invention be limited only by the terms of the appended claims. Like reference numerals refer to like elements throughout the specification.

Hereinafter, a non-oriented electrical steel sheet according to a preferred embodiment of the present invention will be described.

C: not more than 0.005% (not including 0%), Si: not more than 2% (not including 0%), Mn: not more than 0.08%, P: 0.001 to 0.005% of Al, 0.005% or less of N, 0.005% or less of N (not including 0%), 0.005% or less of Ti (not including 0%), 0.03 to 0.2% And the remainder comprises Fe and other inevitably added impurities, wherein Si and Mn satisfy 0.7? ([Si] - [Mn])? 1.7 where [Si] and [Mn] Percent (%) &quot;).

[P] + [Sn] + [Sb]? 0.2 where P, Sn and Sb are the weight percentages of P, Sn and Sb, (%)).

The reasons for limiting the content of the non-oriented electrical steel sheet according to the present invention are as follows.

Si: 2.0 wt% or less

The Si is a main element added to increase the resistivity of the steel to lower the vortex loss during iron loss. However, as the addition amount increases, the element decreases the magnetic flux density. It is difficult to obtain the characteristics of the high magnetic flux density as the addition amount increases. , It is preferable that the addition amount is limited to 2% by weight or less because the ferrite structure hardly contains phase transformation in the production process and is heat-treated only in the ferrite structure to improve the texture.

Mn: 0.08% by weight or less

The Mn is effective not only to increase the resistivity but also to lower the iron loss by addition of Si and Al. However, it is preferable not to add Mn because MnS or MnCuS such as MnS and MnCuS are formed and the magnetism is weakened.

However, it is limited to 0.08% or less in consideration of the amount that is inevitably added in the steelmaking process due to alloying iron and impurities.

Al: 0.005 wt% or less

The Al is added to lower the iron loss as a main element for increasing the specific resistance, but it also serves to decrease the saturation magnetic flux density when added and may also cause the magnetism to be dislocated by forming AlN or the like. Also, it is preferable that Al is not added when the addition amount is increased as in the case of Si, because it affects the ferrite region to enlarge to reduce the phase transformation period.

However, the addition amount thereof is limited to 0.005% or less in consideration of the amount that is inevitably added in the steelmaking process due to alloying iron, impurities and the like.

P: 0.02 to 0.2 wt%

P is known as an element which improves the magnetic properties by restraining the formation of {111} texture structure which is segregated in grain boundaries and harmful to magnetism during recrystallization. However, since it plays a role of inhibiting grain growth by segregation in grain boundaries, its addition amount is limited to 0.02 ~ 0.2% for the improvement of magnetism.

C: 0.005 wt% or less

C increases the austenite area when it is added a lot and increases the phase transformation period. However, it shows an effect of increasing the iron loss by suppressing the crystal growth of ferrite during annealing, and also forming a carbide by binding with Ti etc., When used after processing as a product, the iron loss is increased by magnetic aging, so it should be 0.005% or less.

S: 0.001 to 0.005% by weight or less

S is an element which forms sulfides such as MnS, CuS and (Cu, Mn) S harmful to the magnetic properties, and therefore it is preferable to add S as low as possible. However, when it is added at a content of 0.001% or less, it is disadvantageous to the formation of aggregate structure, and therefore the magnetic property is lowered. Therefore, the content is 0.001% or more and when the content is 0.005% or more, the magnetic property is increased due to the increase of fine sulfides. .

N: 0.005 wt% or less

N is an element which is detrimental to magnetism such as forming a nitride by binding strongly with Al, Ti or the like to inhibit grain growth. Therefore, it is preferable to contain N in a small amount, and in the present invention, N is limited to 0.005 wt% or less.

Ti: 0.005 wt% or less

Ti forms fine carbides and nitrides to inhibit crystal growth. As the amount of Ti is increased, the magnetization becomes poor due to increased carbides and nitrides, resulting in a dislocation of the texture. Therefore, the Ti content is limited to 0.005% or less in the present invention.

At least one of Sn and Sb is contained in an amount of 0.03 to 0.2 wt%

The Sn and Sb are crystal grain boundaries and inhibit the diffusion of nitrogen through the grain boundaries and inhibit the formation of {111} and {112} texture which are harmful to magnetism and increase the {100} and {110} The addition of Sn or Sb alone or in combination of at least 0.2% inhibits the growth of grains by suppressing grain growth and lowers the magnetic properties and lowers the rolling property. Therefore, at least one of Sn and Sb should be added in an amount of 0.03 to 0.2 By weight.

Wherein the contents of Cu, Ni and Cr are added in an amount of 0.05 wt% or less, respectively, and the content of Zr, Mo and V is 0.01% by weight or less.

Since the Cu, Ni and Cr are inevitably added in the steel making process, Cu, Ni and Cr react with the impurity elements to form fine sulfides, carbides and nitrides, which are harmful to the magnetic properties. 0.05% by weight or less.

Further, Zr, Mo, V and the like are preferably strong carbonitride-forming elements, so that they are preferably not added, and they are contained in an amount of 0.01 wt% or less.

In addition to the above composition, the remainder include Fe and other unavoidable impurities that can be added in the steel making process.

In the present invention, Si and Mn are controlled as follows.

0.7? ([Si] - [Mn])? 1.7

(Where, [Si] and [Mn] mean the percentages by weight of Si and Mn, respectively)

Si is an element stabilizing ferrite. When Si is added as the ferrite stabilizing element, there is no phase transformation in the manufacturing process and heat treatment is performed only in the single phase of ferrite. Therefore, it is difficult to improve the texture through phase transformation. Mn increases the phase transformation interval when the amount of the austenite stabilizing element is increased.

That is, when ([Si] - [Mn]) is less than 0.7, there is a problem that the phase transition section is too large and the phase transformation end temperature is low. ([Si] - [Mn]) exceeds 1.7, the phase transition section is small and the phase transformation temperature is high, so that it is difficult to pass the phase transformation section during the heat treatment.

In addition, although Al lowers iron loss and reduces magnetic anisotropy, it has an effect of significantly lowering the magnetic flux density as compared to Mn, and satisfactory magnetization can be obtained by satisfying the composition formula of [Mn] ≥ [Al].

In the present invention, the composition formula of P, Sn, and Sb is as follows.

0.05? ([P] + [Sn] + [Sb])? 0.2

(P), [Sn], and [Sb] refer to weight percent (%) of P, Sn, and Sb, respectively)

P, Sn, and Sb all serve as grain boundary segregation sources, which inhibit the formation of a {111} texture, which is an unfavorable texture to magnetism during recrystallization, and increase {100} and {110} texture structures favorable to magnetism. Therefore, when {(P) + [Sn] + [Sb]) is less than 0.05, {100} and {110}

In addition, when (P] + [Sn] + [Sb] exceeds 0.2, P, Sn, and Sb segregate in the grain boundaries to inhibit grain growth.

In addition, non-oriented electrical steel sheet according to the present invention can satisfy the V _{110} ≥0.2 and V _g ≥0.08.

Where V _{110} is the fraction of the {110} texture of the sum of all orientations and V _g is the fraction of the texture of the (110) [001] texture of the sum of all the orientations.

Further, the magnetic flux density of the non-oriented electrical steel sheet according to the present invention is

B ₅₀ (L)? 1.81 T and B ₅₀ (L) -B ₅₀ (C)? 0.07 T

(Where B ₅₀ (L) represents the magnetic flux density in the rolling direction induced by adding a magnetic field of 5000 A / m, and the magnetic flux density in the width direction perpendicular to the B ₅₀ (C) rolling direction)

Can be satisfied.

The size of the crystal grains in the microstructure of the electrical steel sheet may be 20 to 120 탆.

The contents of Cu, Ni and Cr are added in an amount of 0.05 wt% or less, respectively, and the content of Zr, Mo and V is Each may be 0.01% by weight or less.

Hereinafter, a method for manufacturing a non-oriented electrical steel sheet according to another embodiment of the present invention will be described.

A method for producing a non-oriented electrical steel sheet according to the present invention is a method for producing a non-oriented electrical steel sheet, which comprises 0.005% or less of C (not including 0%), 2% 0.005% or less (inclusive of 0%) of Ti, 0.005% or less of Ti (inclusive of 0% of Ti), 0.08% or less of P, 0.02 to 0.2% of P, 0.001 to 0.005% ), 0.03 to 0.2% of at least one of Sn and Sb, and the balance contains Fe and other inevitably added impurities,

Wherein Si and Mn satisfy 0.7? ([Si] - [Mn])? 1.7 (where [Si] and [Mn] mean the percentages by weight of Si and Mn, respectively) step;

Heating the slab to 1,200 ° C or less and then rolling to produce a hot-rolled steel sheet; Pickling the hot-rolled steel sheet and rolling it to 0.10 to 0.70 mm to produce a cold-rolled steel sheet; And finishing annealing the cold-rolled steel sheet at 850 to 1,100 ° C.

P, Sn and Sb satisfy the relation of 0.05? ([P] + [Sn] + [Sb])? 0.2 where P, Sn and Sb are the weight percentages of P, Sn and Sb %)) Can be satisfied.

C: not more than 0.005% (not including 0%), Si: not more than 2% (not including 0%), Mn: not more than 0.08%, P: 0.001 to 0.005% of Al, 0.005% or less of N, 0.005% or less of N (not including 0%), 0.005% or less of Ti (not including 0%), 0.03 to 0.2% And the remainder comprises Fe and other inevitably added impurities, wherein Si and Mn satisfy 0.7? ([Si] - [Mn])? 1.7 where [Si] and [Mn] (%)) Is heated to 1,200 ° C or lower, followed by rolling to produce a hot-rolled steel sheet.

When the heating temperature is higher than 1,200 ° C, precipitates such as AlN and MnS existing in the slab are reused and then precipitated by hot rolling to suppress crystal growth and decrease magnetism, so the reheating temperature is limited to below 1200 ° C.

Finishing rolling in hot rolling can be finished in a single phase region of ferrite having a temperature of {A ₁ (° C) - 40 ° C} or lower.

The reason why the finish rolling is performed in a single-phase ferrite region of {A ₁ temperature (占 폚 - 40 占 폚) or less is that when the finish rolling is carried out in the austenite / ferrite region, recrystallization is completed by the phase transformation upon cooling after hot rolling, This is because the effect of improving the texture and improving the magnetic properties by the plate annealing process is reduced.

In addition, the final reduction ratio can be reduced to 20% or less for plate shape calibration.

The heat-hot-rolled steel sheet thus prepared is rolled up at 700 ° C or less and cooled in air.

The wound hot-rolled steel sheet may further include annealing the hot-rolled steel sheet.

The hot-rolled sheet annealing is performed at 1000 to 1200 ° C for improving the magnetic properties, and can be carried out in the austenite single phase region above the A ₃ temperature (° C).

When the hot-rolled sheet annealing is performed in the austenite single-phase region above the A ₃ temperature, the effect of improving the aggregate structure due to the phase transformation can be maximized.

When the annealing temperature of the hot-rolled sheet is lower than 1000 占 폚, grain growth is insufficient and the effect of improving the aggregate structure is small. When the annealing temperature exceeds 1200 占 폚, the productivity is lowered. Surface defects become excessive.

The hot rolled sheet is pickled and cold rolled.

The cold rolling can be finally rolled to a thickness of 0.10 mm to 0.70 mm. If necessary, it can be subjected to primary cold rolling and intermediate annealing, followed by secondary cold rolling, and the final rolling reduction can be in the range of 50 to 95%.

The cold-rolled steel sheet is subjected to cold-rolled sheet annealing (finish annealing). In the step of annealing the cold-rolled sheet, the temperature of the cracking of the cold-rolled sheet during annealing (finish annealing) is 850 to 1100 ° C. When the annealing temperature of the cold rolled sheet is below 850 DEG C, the growth of the crystal grains is insufficient and the {111} texture, which is harmful to the magnetism, increases. At above 1100 DEG C, the crystal grains grow excessively and may have a bad influence on the magnetism.

The cold rolled annealed sheet may be subjected to an insulating coating treatment.

Hereinafter, a method of manufacturing a non-oriented electrical steel sheet according to the present invention will be described in detail with reference to examples. The following examples are illustrative of the present invention only and are not intended to limit the scope of the present invention.

&Lt; Example 1 >

The effects of elemental elements and hot-rolling finishing temperature were investigated by varying the amounts of Si, Mn, Al, P, Sn, and Sb. Each steel ingot was heated at 1190 DEG C, hot rolled to a thickness of 2.3 mm, and then wound. The hot-rolled steel sheet wound and cooled in air was annealed at 1100 ° C for 2 minutes, pickled, cold-rolled to a thickness of 0.35 mm, and subjected to final annealing at 900 ° C for 80 seconds.

Steel grade C Si Mn P S Al N Ti Sn Sb A ₃ A ₁ X1 0.0015 0.94 0.05 0.064 0.0018 0.004 0.0037 0.0009 0.02 0.09 990 959 X2 0.0029 0.78 0.07 0.023 0.0038 0.003 0.0031 0.0006 0 0.02 971 930 X3 0.0013 1.06 0.01 0.072 0.0036 0.001 0.0025 0.0016 0.04 0 1007 975 X4 0.0046 1.64 0.06 0.087 0.0026 0.004 0.0014 0.0046 0.09 0 1083 995 X5 0.0038 0.87 0.04 0.045 0.004 0.005 0.0031 0.0033 0.1 0.05 982 931 X6 0.0025 0.67 0.05 0.15 0.0044 0.003 0.004 0.0026 0.07 0.04 963 928 X7 0.0047 0.8 0.08 0.018 0.0013 0.003 0.0036 0.0041 0 0.06 970 912 X8 0.0032 1.24 0.01 0.122 0.0011 0.005 0.0018 0.0014 0 0.03 1029 973 X9 0.0022 1.38 0.04 0.056 0.0037 0.001 0.0019 0.0032 0.07 0.05 1045 992 X10 0.0038 0.73 0.06 0.028 0.0029 0.002 0.0034 0.0021 0.05 0.12 966 918 X11 0.0043 0.82 0.08 0.143 0.0023 0.002 0.0038 0.0024 0.07 0.08 972 917 X12 0.0033 1.45 0.06 0.051 0.0035 0.003 0.0022 0.0035 0.07 0.07 1053 987

Steel grade [Si] - [Mn] [P] + [Sn] +
[Sb] Finish rolling
Temperature (℃) V _g V _{110} Grain size
(탆) B ₅₀ (L) B ₅₀ (L) -B ₅₀ (C) Remarks X1 0.89 0.174 868 0.09 0.22 46 1.87 0.11 Honor X2 0.71 0.043 894 0.07 0.17 57 1.78 0.05 Comparative Example X3 1.05 0.112 867 0.09 0.21 59 1.85 0.09 Honor X4 1.58 0.177 886 0.11 0.24 61 1.83 0.07 Honor X5 0.83 0.195 871 0.1 0.25 43 1.84 0.08 Honor X6 0.62 0.26 879 0.05 0.18 38 1.78 0.06 Comparative Example X7 0.72 0.078 882 0.06 0.22 49 1.78 0.04 Comparative Example X8 1.23 0.152 861 0.11 0.23 61 1.82 0.08 Honor X9 1.34 0.176 904 0.09 0.23 64 1.82 0.09 Honor X10 0.67 0.198 896 0.08 0.19 37 1.77 0.05 Comparative Example X11 0.74 0.293 875 0.09 0.15 19 1.77 0.06 Comparative Example X12 1.39 0.191 881 0.12 0.22 55 1.81 0.1 Honor

1) _Iron loss (W _15/50 ) means the average loss (W / kg) in the rolling direction and the rolling direction perpendicular to the magnetic flux density of 1.5 Tesla at 50 Hz frequency.

2) The magnetic flux density (B ₅₀ ) means the magnitude of the magnetic flux density (Tesla) when a magnetic field of 5000 A / m is added.

3) In Table 1, A ₃ , A ₁ is the A ₃ temperature (° C) and A ₁ temperature (° C) according to each composition system.

EBSD and X-ray pole figure test were performed for each specimen, and the fraction of the texture was measured. The grain size was measured using the intercept method.

As shown in the above Table 2, the composition formula of [Si], [Mn], [Al], [P], [Sn], [Sb] and 0.7 ≤ [Si] - [Mn] ([P], [Sn], and [Sn]) of 0.05 [(P) + [Sn] + [Sb] X3, X4, and X4 performed in a single-phase ferrite phase having a hot-rolling temperature of not higher than {A ₁ temperature (占 폚) - 40 占 폚] X5, X8, X9, and X12 satisfy the requirements of V _g ≥0.08 and V _{110} ≥0.2 as a result of the aggregate structure measurement after cold rolled sheet annealing (ACL) and satisfy the grain size of 20 ~ 120 ㎛. As a result, The magnetic flux density B ₅₀ (L) was also high, and the magnetic flux density difference between the rolling direction and the direction perpendicular to the rolling direction was as large as 0.07T or more.

X2, on the other hand, satisfied the compositional formula of 0.7 [(Si) - [Mn]) ≤1.7 and the addition amount of [Si], [Mn], [Al] (Pb) + [Sn] + [Sb] ≤0.2 and the finish rolling temperature in hot rolling (A ₁ temperature -40 ° C) is less than because of the texture measurements hayeotgi not satisfy V ≥0.08 _g and V _{110} ≥0.2 failure to, and as a result was also was low magnetic flux density B ₅₀ (L) in the rolling direction of the magnetic flux density in the rolling direction and the direction perpendicular to the rolling The difference was small.

X6 satisfies the addition amount of [Si], [Mn], [Al], [P], [Sn] and [Sb], but the composition formula of 0.7? ([Si] - [Mn] P _< .05 and V _{110} ≥0.2. As a result, the magnetic flux density in the rolling direction B ₅₀ (L), and the magnetic flux density difference between the rolling direction and the direction perpendicular to the rolling direction was small.

On the other hand, when X7 is an amount of addition of [Si], [Mn], [Al], [Sn] and [Sb] + [Sb]) ≤0.2 were all satisfied, but the addition amount of [P] did not satisfy the control range and the finish rolling temperature during hot rolling did not satisfy the range of {A ₁ temperature (° C) - 40 ° C} mothayeo texture measurements were not satisfied the V ≥0.08 _g, as a result the magnetic flux density in the rolling direction B ₅₀ (L) also were lower was also less difference in the magnetic flux density in the rolling direction and rolling in the vertical direction.

X10 satisfied the composition formula of 0.7? ([Si] - [Mn])? 1.7, while satisfying the addition amounts of [Si], [Mn], [Al], [Sn] and [Sb] As a result of the texture measurement, it was not possible to satisfy V _{110} ≥0.2 because the finishing rolling temperature (A ₁ temperature -40 ° C) or less was not satisfied. As a result, the magnetic flux density B ₅₀ (L) And the difference in magnetic flux density between the rolling direction and the direction perpendicular to the rolling direction was small.

On the other hand, in X11, the amount of addition of [Si], [Mn], [Al], [Sn] and [Sb] was satisfied but the compositional formula of 0.05? ([P] + [Sn] + [Sb] were filled, texture measurements were not satisfied the V _{110} ≥0.2, was not satisfied the 20 ~ 120㎛ FIG grain size was found as a result is also low magnetic flux density B ₅₀ (L) in the rolling direction rolling direction And the difference in magnetic flux density in the direction perpendicular to the rolling direction.

&Lt; Example 2 >

A steel ingot was prepared as shown in Table 3 through vacuum melting. The effects of hot rolling finishing temperature, annealing of hot - rolled sheet and annealing temperature of cold - rolled sheet on aggregate texture, grain size and magnetism were investigated. Each steel ingot was heated at 1150 占 폚, hot rolled to a thickness of 2.5 mm, and then wound. The hot-rolled steel sheet wound and cooled in air was annealed at 950 to 1150 ° C for 90 seconds, pickled and cold-rolled to a thickness of 0.35 mm, and subjected to final annealing at 800 to 1150 ° C for 100 seconds.

Steel grade C Si Mn P S Al N Ti Sn Sb A ₃ A ₁ Y1 0.0031 1.04 0.01 0.024 0.0013 0.002 0.0016 0.0016 0.03 0 1003 955 Y2 0.0049 0.78 0.05 0.027 0.0026 0.001 0.0009 0.0019 0.01 0.04 970 912 Y3 0.0034 1.09 0.08 0.037 0.0034 0.003 0.0049 0.0011 0.06 0 1003 949 Y4 0.0012 1.24 0.07 0.08 0.0021 0.005 0.0034 0.0037 0 0.09 1025 986 Y5 0.0018 1.64 0.08 0.046 0.0038 0.003 0.0021 0.0026 0.07 0.03 1083 1020 Y6 0.0009 1.37 0.04 0.08 0.0039 0.004 0.0026 0.0035 0.06 0.05 1046 1005 Y7 0.0025 1.34 0.06 0.085 0.0032 0.004 0.0019 0.004 0.08 0.02 1038 984 Y8 0.0037 1.1 0.01 0.064 0.0045 0.002 0.0018 0.0016 0.1 0.01 1010 954 Y9 0.0023 1.29 0.05 0.055 0.0025 0.003 0.0031 0.0033 0 0.06 1032 982 Y10 0.0018 0.85 0.03 0.042 0.0014 0.004 0.0022 0.004 0.04 0 982 951

Steel grade [Si] - [Mn] [P] + [Sn] +
[Sb] Wrap-up
Rolling
Temperature (℃) Hot-rolled plate
Annealing temperature (캜) Cold rolled plate
Annealing temperature (캜) V _g V _{110} Grain size
(탆) B ₅₀ (L) B _{50 (} L) -B ₅₀ (C) Remarks Y1 1.03 0.054 879 990 940 0.07 0.15 74 1.78 0.04 Comparative Example Y2 0.73 0.077 885 1030 1110 0.05 0.14 99 1.79 0.05 Comparative Example Y3 1.01 0.097 873 1080 1030 0.09 0.23 81 1.85 0.09 Honor Y4 1.17 0.17 864 1050 990 0.12 0.24 77 1.85 0.11 Honor Y5 1.56 0.146 894 1100 1050 0.11 0.22 98 1.83 0.08 Honor Y6 1.33 0.19 902 1070 1070 0.08 0.21 113 1.84 0.01 Honor Y7 1.28 0.185 882 1030 830 0.04 0.18 61 1.77 0.05 Comparative Example Y8 1.09 0.174 888 1000 1120 0.06 0.18 125 1.76 0.04 Comparative Example Y9 1.24 0.115 874 1040 1060 0.09 0.21 102 1.82 0.07 Honor Y10 0.82 0.082 868 1110 1020 0.1 0.22 88 1.86 0.11 Honor

1) _Iron loss (W _15/50 ) is the rolling direction when a magnetic flux density of 1.5 Tesla is induced at a frequency of 50 Hz, and the iron loss (W _15/50 ) when a magnetic flux density of 1.5 Tesla is induced at a frequency of 50 Hz. Direction Mean vertical loss (W / kg).

2) The magnetic flux density (B ₅₀ ) means the magnitude of the magnetic flux density (Tesla) when a magnetic field of 5000 A / m is added.

3) In Table 3, A ₃ , A ₁ is the A ₃ temperature (° C) and A ₁ temperature (° C) according to each composition system.

As shown in Table 4, the composition formula of [Si], [Mn], [Al], [P], [Sn], [Sb] and 0.7 ≦ [Si] - [Mn] ([P], [Sn], and [Sn]) of 0.05 [(P) + [Sn] + [Sb] , [Sb] are respectively P, Sn, satisfying the addition amount (% by weight)) of Sb, and the hot finish rolling {a ₁ temperature (℃) - 40 ℃} hot-rolled sheet annealing was performed in the ferrite single-phase region below (APL) and cold-rolled sheet annealing, steel grade which satisfies (ACL) conditions Y3, Y4, Y5, Y6, Y9, Y10 was satisfies the cold-rolled sheet annealing (ACL) after the texture measurements ≥0.08 V _g and V _{110} ≥0.2 And grain size of 20 ~ 120 ㎛. As a result, the magnetic flux density B ₅₀ (L) in the rolling direction was also high, and the magnetic flux density difference between the rolling direction and the direction perpendicular to the rolling direction was larger than 0.07T.

On the other hand, Y1 satisfies the composition formula of 0.7? ([Si] - [Mn])? 1.7 and 0.05? ([P] + [Sn] + [Sb]? 0.2 in the addition amount of the alloy element, (A ₁ temperature (° C) - 40 ° C}, but it did not satisfy the annealing condition of hot-rolled sheet (carried out in a single-phase austenite region above A ₃ temperature), and V _g ≥0.08 and V _{Since {110}} ≥0.2 was not satisfied, the magnetic flux density B ₅₀ (L) in the rolling direction was also low, and the magnetic flux density difference in the rolling direction and the direction perpendicular to the rolling direction was small.

In addition, Y2 satisfied both the addition amount of the alloying element and the above composition formula, but the hot rolling temperature did not satisfy the range of {A ₁ temperature (° C) - 40 ° C} below the ACL annealing temperature, As a result, V _g ≥0.08 and V _{110} ≥0.2 were not satisfied. As a result, the magnetic flux density B ₅₀ (L) in the rolling direction was also low and the rolling direction and the direction perpendicular to the rolling direction The difference in magnetic flux density was small.

Y7 and Y8 satisfied both the addition amount of alloying elements and the composition formula and the finish rolling temperature during hot rolling satisfied the range of {A ₁ temperature (° C) - 40 ° C}, but did not satisfy the APL annealing temperature, even lower than the management range, and the resulting texture measurement result as the high work V _g for ≥0.08 and V _{110} were not satisfied with the ≥0.2, Y8 got excessive grain sizes also appear as a result, the rolling direction The magnetic flux density B ₅₀ (L) was also low and the magnetic flux density difference between the rolling direction and the direction perpendicular to the rolling direction was small.

While the present invention has been described in connection with certain exemplary embodiments, it will be understood by those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the invention as defined by the appended claims.

It is therefore to be understood that the above-described embodiments are illustrative in all aspects and not restrictive. The scope of the present invention is defined by the appended claims rather than the detailed description, and all changes or modifications derived from the meaning and scope of the claims and their equivalents should be interpreted as being included in the scope of the present invention .

Claims (14)

C: not more than 0.005% (not including 0%), Si: not more than 2% (not including 0%), Mn: not more than 0.08%, P: 0.001 to 0.005% of Al, 0.005% or less of N, 0.005% or less of N (not including 0%), 0.005% or less of Ti (not including 0%), 0.03 to 0.2% , The remainder comprising Fe and other inevitably added impurities,
The Si and Mn
0.7? ([Si] - [Mn])? 1.7
(Where, [Si] and [Mn] mean the percentages by weight of Si and Mn, respectively)
Of the non-oriented electrical steel sheet. The method according to claim 1,
P, Sn, and Sb satisfy 0.05? ([P] + [Sn] + [Sb]
(P), [Sn], and [Sb] refer to weight percent (%) of P, Sn, and Sb, respectively)
Of the total thickness of the non-oriented electrical steel sheet. 3. The method according to claim 1 or 2,
Wherein the non-oriented electrical steel sheet satisfies V _{110}? 0.2 and V _g? 0.08.
Where V _{110} is the fraction of the {110} texture of the sum of all orientations and V _g is the fraction of the texture of the (110) [001] texture of the sum of all the orientations. The method of claim 3,
The magnetic flux density of the electrical steel sheet is B ₅₀ (L) ≥1.81 T and
B ₅₀ (L) -B ₅₀ (C)? 0.07 T
(Where B ₅₀ (L) represents the magnetic flux density in the rolling direction induced by adding a magnetic field of 5000 A / m, and the magnetic flux density in the width direction perpendicular to the B ₅₀ (C) rolling direction)
Of the non-oriented electrical steel sheet. 5. The method of claim 4,
Wherein the contents of Cu, Ni and Cr are added in an amount of 0.05 wt% or less, respectively, and the content of Zr, Mo and V is 0.01% by weight or less. 6. The method of claim 5,
Wherein the grain size of the microstructure of the electrical steel sheet is 20 to 120 占 퐉. C: not more than 0.005% (not including 0%), Si: not more than 2% (not including 0%), Mn: not more than 0.08%, P: 0.001 to 0.005% of Al, 0.005% or less of N, 0.005% or less of N (not including 0%), 0.005% or less of Ti (not including 0%), 0.03 to 0.2% , The remainder comprising Fe and other inevitably added impurities,
The Si and Mn
0.7? ([Si] - [Mn])? 1.7
(Where, [Si] and [Mn] mean the percentages by weight of Si and Mn, respectively)
Providing a slab that satisfies &lt; RTI ID = 0.0 &gt;
Heating the slab to 1,200 ° C or less and then rolling to produce a hot-rolled steel sheet;
Pickling the hot-rolled steel sheet and rolling it to 0.10 to 0.70 mm to produce a cold-rolled steel sheet; And
And finishing and annealing the cold-rolled steel sheet at 850 to 1,100 ° C. 8. The method of claim 7,
P, Sn, and Sb satisfy 0.05? ([P] + [Sn] + [Sb]
(P), [Sn], and [Sb] refer to weight percent (%) of P, Sn, and Sb, respectively)
Of the non-oriented electrical steel sheet. 9. The method according to any one of claims 7 to 8,
In the step of manufacturing the hot-rolled steel sheet,
Wherein the finish rolling is finished in a single-phase region of ferrite having a temperature of {A ₁ (° C) - 40 ° C} or less. 9. The method according to any one of claims 7 to 8,
Further comprising the step of annealing the hot-rolled steel sheet at a temperature of 1,000 to 1,200 ° C,
Wherein the annealing of the hot-rolled steel sheet is performed in a single-phase austenite region having an A ₃ temperature (캜) or higher. 11. The method of claim 10,
Wherein the electric steel sheet after completion of the finish annealing satisfies V _{110}? 0.2 and V _g? 0.08.
Where V _{110} is the fraction of the {110} texture of the sum of all orientations and V _g is the fraction of the texture of the (110) [001] texture of the sum of all the orientations. 11. The method of claim 10,
The magnetic flux density of the electric steel sheet after finishing annealing is B ₅₀ (L)? 1.81 T and
B ₅₀ (L) -B ₅₀ (C)? 0.07 T
(Where B ₅₀ (L) represents the magnetic flux density in the rolling direction induced by adding a magnetic field of 5000 A / m, and the magnetic flux density in the width direction perpendicular to the B ₅₀ (C) rolling direction)
Of the non-oriented electrical steel sheet. 13. The method of claim 12,
Wherein the contents of Cu, Ni and Cr are added in an amount of 0.05 wt% or less, respectively, and the content of Zr, Mo and V is 0.01% by weight or less. 14. The method of claim 13,
Wherein the size of the crystal grains in the microstructure of the electric steel sheet after finishing annealing is 20 to 120 占 퐉.