Non-oriented electrical steel sheet and method for producing same
A non-oriented electrical steel sheet according to an exemplary embodiment of the present invention includes 2.0 to 4.0% of Si, 0.05 to 1.5% of Al, 0.05 to 2.5% of Mn, equal to or less than 0.005% of C (excluding 0%), equal to or less than 0.005% of N (excluding 0%), 0.001 to 0.1% of Sn, 0.001 to 0.1% of Sb, 0.001 to 0.1% of P, 0.001 to 0.01% of As, 0.0005 to 0.01% of Se, 0.0005 to 0.01% of Pb, 0.0005 to 0.01% of Bi, a remainder of Fe, and inevitable impurities, as wt %, wherein a Taylor factor (M) of each crystal grain included in a steel sheet is expressed in Formula 1, and an average Taylor factor value of the steel sheet is equal to or less than 2.75: M = σ τ CRSS [ Formula 1 ] (here, σ is a macro stress, and τ CRSS is a critical resolved shear stress).
1. A non-oriented electrical steel sheet comprising
2.0 to 4.0% of Si, 0.05 to 1.5% of Al, 0.05 to 2.5% of Mn, equal to or less than 0.005% of C (excluding 0%), equal to or less than 0.005% of N (excluding 0%), 0.001 to 0.1% of Sn, 0.001 to 0.1% of Sb, 0.001 to 0.1% of P, 0.001 to 0.01% of As, 0.0005 to 0.01% of Se, 0.0005 to 0.01% of Pb, 0.0005 to 0.01% of Bi, a remainder of Fe, and inevitable impurities, as wt %,
wherein a Taylor factor (M) of each crystal grain included in a steel sheet is expressed in Formula 1, and an average Taylor factor value of the steel sheet is equal to or less than 2.75;
M
=
σ
τ
crss
[
Formula
1
]
here, σ is a macro stress, and τ CRSS is a critical resolved shear stress, and
wherein the steel sheet satisfies Formula 2 and Formula 3:
3×([C]+[N])≤([Sn]+[Sb]+[P]+[As]+[Se]+[Pb]+[Bi])≤15×([C]+[N]) [Formula 2]
([Sn]+[Sb])≥[P]≥([As]+[Se])≥([Pb]+[Bi]) [Formula 3]
here, [C], [N], [Sn], [Sb], [P], [As], [Se], [Pb], and [Bi] are contents (wt %) of C, N, Sn, Sb, P, As, Se, Pb, and Bi.
2. The non-oriented electrical steel sheet of claim 1 , further comprising 0.0005 to 0.01 wt % of Nb, 0.0005 to 0.01 wt % of Ti, and 0.0005 to 0.01 wt % of V.
3. The non-oriented electrical steel sheet of claim 2 , wherein Formula 4 is satisfied:
([Nb]+[Ti]+[V])≤([C]+[N]) [Formula 4]
(here, [C], [N], [Nb], [Ti], and [V] are contents (wt %) of C, N, Nb, and V).
4. The non-oriented electrical steel sheet of claim 1 , further comprising
at least one of equal to or less than 0.005 wt % of S, equal to or less than 0.025 wt % of Cu, equal to or less than 0.002 wt % of B, equal to or less than 0.005 wt % of Mg, and equal to or less than 0.005 wt % of Zr.
5. The non-oriented electrical steel sheet of claim 1 , wherein
an average crystal grain diameter is 60 to 170 μm.
6. A method for manufacturing a non-oriented electrical steel sheet, comprising:
manufacturing a slab including 2.0 to 4.0% of Si, 0.05 to 1.5% of Al, 0.05 to 2.5% of Mn, equal to or less than 0.005% of C (excluding 0%), equal to or less than 0.005% of N (excluding 0%), 0.001 to 0.1% of Sn, 0.001 to 0.1% of Sb, 0.001 to 0.1% of P, 0.001 to 0.01% of As, 0.0005 to 0.01% of Se, 0.0005 to 0.01% of Pb, 0.0005 to 0.01% of Bi, a remainder of Fe, and inevitable impurities, as wt %;
heating the slab;
manufacturing a hot-rolled steel sheet by hot rolling the slab;
manufacturing a cold-rolled steel sheet by cold rolling the hot-rolled steel sheet; and
final annealing the cold-rolled steel sheet,
wherein a Taylor factor (M) of each crystal grain included in the steel sheet is expressed in Formula 1, and an average Taylor factor value of the steel sheet is equal to or less than 2.75;
M
=
σ
τ
crss
Formula
1
here, σ is a macro stress, and τ CRSS is a critical resolved shear stress, and
wherein the slab satisfies Formula 2 and Formula 3:
3×([C]+[N])≤([Sn]+[Sb]+[P]+[As]+[Se]+[Pb]+[Bi])≤15×([C]+[N]) [Formula 2]
([Sn]+[Sb])≥[P]≥([As]+[Se])≥([Pb]+[Bi]) [Formula 3]
here, [C], [N], [Sn], [Sb], [P], [As], [Se], [Pb], and [Bi] are contents (wt %) of C, N, Sn, Sb, P, As, Se, Pb, and Bi.
7. The method of claim 6 , further comprising
after the manufacturing of a hot-rolled steel sheet,
performing hot-rolled steel sheet annealing on the hot-rolled steel sheet.