Non-oriented electrical steel sheet and manufacturing method therefor

1. A non-oriented electrical steel sheet comprising 1.5 to 4.0 wt % of Si, 0.1 to 1.5 wt % of Al, 0.1 to 1.5 wt % of Mn, 0.005 wt % or less, excluding 0% of C, 0.005 wt % or less, excluding 0% of N, 0.005 wt % or less, excluding 0% of Ti, 0.001 to 0.005 wt % of S, 0.1 wt % or less, excluding 0% of P, 0.02 to 0.2 wt % of a sum of Sn and Sb, and a balance of Fe and other inevitable impurities,

wherein both Sn and Sb are included together,

wherein the electrical steel sheet satisfies the following Formulas 1, 2, 3, and 4:

0.9≤[Al]+[Mn]≤2.1  [Formula 1]

0.2≤([Si]+[Al]+[Mn]/2)*([P]+[Sn]+[Sb])≤0.4  [Formula 2]

( G s center −G s surface )/( G s center *t)≤0.5 (mm −1 )  [Formula 3]

0.2≤( V {012}<121> +V {111}<112> )/( V {001}<310> +V {139}<310> )≤0.8  [Formula 4]

in Formula 1 and Formula 2, [Al], [Mn], [Si], [P], [Sn], and [Sb] represent the content in weight % of Al, Mn, Si, P, Sn, and Sb, respectively,

in Formula 3, t represents the thickness in mm of the non-oriented electrical steel sheet, Gs surface represents the average grain size in μm from 0 to t/4 or 3t/4 to t based on the thickness direction of the non-oriented steel sheet, and Gs center represents the average grain size in μm from more than t/4 to less than 3t/4 based on the thickness direction of the non-oriented steel sheet, and

in Formula 4, V {012}<121> , V {111}<112> , V {001}<310> , and V {139}<310> represent the volume fraction of an aggregation structure having an orientation within 15° at {012}<121>, {111}<112>, {001}<310>, and {139}<310>, respectively.

2. The non-oriented electrical steel sheet of claim 1 , wherein

the steel sheet thereof comprises at least one of 0.05 wt % or less, excluding 0% of Cu, 0.05 wt % or less, excluding 0% of Ni, 0.05 wt % or less, excluding 0% of Cr, 0.01 wt % or less, excluding 0% of Zr, 0.01 wt % or less, excluding 0% of Mo, and 0.01 wt % or less, excluding 0% of V.

3. A method for manufacturing a non-oriented electrical steel sheet, comprising:

heating a slab comprising 1.5 to 4.0 wt % of Si, 0.1 to 1.5 wt % of Al, 0.1 to 1.5 wt % of Mn, 0.005 wt % or less, excluding 0% of C, 0.005 wt % or less, excluding 0% of N, 0.005 wt % or less, excluding 0% of Ti, 0.001 to 0.005 wt % of S, 0.1 wt % or less, excluding 0% of P, 0.02 to 0.2 wt % of a sum of Sn and Sb, and a balance of Fe and other inevitable impurities, and satisfying Formula 1 and Formula 2;

producing a hot-rolled sheet by hot rolling the slab;

producing a cold-rolled sheet by cold rolling the hot-rolled sheet; and

performing cold-rolled sheet annealing to satisfy following Formula 5,

wherein both Sn and Sb are included together,

wherein the electrical steel sheet satisfies the following Formulas 4:

0.9≤[Al]+[Mn]≤2.1  [Formula 1]

0.2≤([Si]+[Al]+[Mn]/2)*([P]+[Sn]+[Sb])≤0.4  [Formula 2]

0.2≤( V {012}<121> +V {111}<112>)/( V {001}<310> +V {139}<310>)≤0.8  [Formula 4]

0.2≤v/s≤0.6  [Formula 5]

in Formula 1 and Formula 2, [Al], [Mn], [Si], [P], [Sn], and [Sb] represent the content in weight % of Al, Mn, Si, P, Sn, and Sb, respectively,

in Formula 4, V{012}<121>, V{111}<112>, V{001}<310>, and V{139}<310> represent the volume fraction of an aggregation structure having an orientation within 15° at {012}<121>, {111}<112>, {001}<310>, and {139}<310>, respectively, and

in Formula 5, v represents an average heating rate in ° C./sec from a starting temperature of 650 to 750° C. to a soaking temperature of the cold rolled sheet, and s represents the soaking time in seconds while being maintained at the soaking temperature of the cold-rolled sheet.

4. The method for manufacturing a non-oriented electrical steel sheet of claim 3 , wherein

the slab thereof comprises at least one of 0.05 wt % or less, excluding 0% of Cu, 0.05 wt % or less, excluding 0% of Ni, 0.05 wt % or less, excluding 0% of Cr, 0.01 wt % or less, excluding 0% of Zr, 0.01 wt % or less, excluding 0% of Mo, and 0.01 wt % or less, excluding 0% of V.

5. The method for manufacturing a non-oriented electrical steel sheet of claim 3 , wherein

in the performing cold rolled sheet annealing,

the soaking temperature is 850 to 1050° C.

6. The method for manufacturing a non-oriented electrical steel sheet of claim 3 , wherein

the method further comprises performing the hot-rolled sheet annealing at 950 to 1150° C., after producing a hot-rolled sheet by hot rolling the slab.