An annealing separator composition for a grain-oriented electrical steel sheet according to an exemplary embodiment of the present invention contains a composite metal oxide containing Mg and a metal M, wherein the metal M is one or more of Be, Ca, Ba, Sr, Sn, Mn, Fe, Co, Ni, Cu, and Zn.

A non-oriented electrical steel sheet according to an exemplary embodiment of the present invention includes, in wt%, Si: 1.5 to 4.0%, Al: 0.5 to 1.5%, Mn: 0.05 to 0.55%, C: 0.005% or less, Ti: 0.004% or less (excluding 0%), N: 0.005% or less (excluding 0%), S: 0.005% or less (excluding 0%), and Cu: 0.01% or less (excluding 0%), and the balance of Fe and inevitable impurities, and satisfies Formula 1 and Formula 2 below.

[N]≤0.005×([Al]×[Ti])  [Formula 1]

[S]≤0.01×([Mn]+[Cu])  [Formula 2]

(In Formula 1 and Formula 2, [N], [Al], [Ti], [S], [Mn], and [Cu] represent a content (wt %) of N, Al, Ti, S, Mn, and Cu, respectively).

An embodiment of the present invention provides a non-oriented electrical steel sheet including. in wt%: Si: 2.5 to 4.0 %, Mn: 0.1 to 1.0 %, Al: 0.5 to 1.5 %, P: 0.002 to 0.015 %, and As: 0.002 to 0.01 %, and the balance of Fe and inevitable impurities, and satisfying Formula 1 and Formula 2.

[00001]$0.005\le \left(\left[\text{P}\right]+\left[\text{As}\right]\right)\le 0.015$

(In Formula 1, [P] and [As] represent a content (wt%) of P and As, respectively.)

[00002]$\left[\text{STD}\right]\le 0.7\times \left[\text{GS}\right]$

([GS] is an average grain size (.Math.m) measured when 10,000 or more grains having a grain size of 5 to 500 .Math.m are observed on a surface of the steel sheet, and STD is a standard deviation (.Math.m) at that time.)

What is provided is a steel sheet for a non-oriented electrical steel sheet containing, in mass %, C: 0.0040% or less, Si: 1.9% or more and 3.5% or less, Al: 0.10% or more and 3.0% or less, Mn: 0.10% or more and 2.0% or less, P: 0.09% or less, S: 0.005% or less, N: 0.0040% or less, B: 0.0060% or less, and the remainder consisting of Fe and impurities, in which the recrystallization rate of the structure of a sheet thickness-direction cross section at each position 10 mm apart toward the sheet width center from each of both end portions in the sheet width direction is less than 50%, and, when the sheet width is represented by W, the recrystallization rate of the structure of a sheet thickness-direction cross section at the position of ¼W from each of both end portions in the sheet width direction is 50% or more.

A grain-oriented electrical steel sheet that includes a base coating with a high TiN ratio advantageous for the application of tension to the steel sheet and has excellent magnetic property is provided. The grain-oriented electrical steel sheet includes: a base coating having a peak value PTiN of TiN in the form of osbornite, observed in a range of 42°<2θ<43° and a peak value PMg.sub.2SiO.sub.4 of Mg.sub.2SiO.sub.4 in the form of forsterite, observed in a range of 35°<2θ<36° of both more than 0 and satisfying a relationship PTiN≧PMg.sub.2SiO.sub.4, in thin-film X-ray diffraction analysis; and an iron loss W.sub.17/50 of 1.0 W/kg or less.

When a non-oriented electrical steel sheet is produced by hot rolling a slab containing, by mass %, C: not more than 0.0050%, Si: 1.5-5.0%, Mn: 0.20-3.0%, sol. Al: not more than 0.0050%, P: not more than 0.2%, S: not more than 0.0050% and N: not more than 0.0040% to form a hot rolled sheet, cold rolling the hot rolled sheet without conducting a hot band annealing and then subjecting to a finish annealing, a compositional ratio of CaO in oxide-based inclusions existing in the slab defined by CaO/(SiO.sub.2+Al.sub.2O.sub.3+CaO) is set to not less than 0.4 and/or a compositional ratio of Al.sub.2O.sub.3 defined by Al.sub.2O.sub.3/(SiO.sub.2+Al.sub.2O.sub.3+CaO) is set to not less than 0.3, and a coiling temperature in the hot rolling is set to not lower than 650° C.

A non-oriented electrical steel sheet includes C: 0 to 0.0050 mass %, Si: 0.50 to 2.70 mass %, Mn: 0.10 to 3.00 mass %, Al: 1.00 to 2.70 mass %, and P: 0.050 to 0.100 mass %. In the non-oriented electrical steel sheet, Al/(Si+Al+0.5×Mn) is 0.50 to 0.83, Si+Al/2+Mn/4+5×P is 1.28 to 3.90, Si+Al+0.5×Mn is 4.0 to 7.0, the ratio of the intensity of {100} plane I{100} to the intensity of {111} plane I{111} is 0.50 to 1.40, the specific resistance is 60.0×10.sup.−8 Ω.Math.m or higher at room temperature, and the thickness is 0.05 mm to 0.40 mm.

Provided is an oriented electrical steel sheet including a groove existing on the surface of the electrical steel sheet and a forsterite layer formed on a part or all of the surface of the electrical steel sheet, in which forsterite which is extended from the forsterite layer and penetrates to a base steel sheet in an anchor form is present on the surface of the side of the groove.

An oriented electrical steel sheet according to an embodiment of the present invention includes, in a unit of wt %, Si at 1.0 wt % to 5.0 wt %, C at 0.005 wt % or less (excluding 0 wt %), Mn at 0.001 wt % to 0.1 wt %, Cu at 0.001 wt % to 0.1 wt %, S at 0.001 wt % to 0.020 wt %, Se at 0.001 wt % to 0.050 wt %, Al at 0.0005 wt % to 0.010 wt %, N at 0.0005 wt % to 0.005 wt %, and the remainder of Fe and inevitable impurities.

The oriented electrical steel sheet according to the embodiment of the present invention satisfies Equation 1.

16≤(10×[Mn]+[Cu])/([S]+[Se])+(0.02−[Al])/[N]≤20  [Equation 1]

(In Equation 1, [Mn], [Cu], [S], [Se], [Al], and [N] represent contents (wt %) of Mn, Cu, S, Se, Al, and N, respectively.)

A method of production non grain-oriented Fe—Si steel sheet is provided. The method includes the steps of melting a steel composition that contains in weight percentage: C≤0.006, 2.0≤Si≤5.0, 0.1≤Al≤3.0, 0.1≤Mn≤3.0, N≤0.006, 0.04≤Sn≤0.2, S≤0.005, P≤0.2, Ti≤0.01, the balance being Fe and other inevitable impurities, casting said melt into a slab, reheating said slab, hot rolling said slab, coiling said hot rolled steel, optionally annealing the hot rolled steel, cold rolling, annealing and cooling the cold rolled steel down to room temperature.