Oriented electrical steel sheet and manufacturing method therefor
Provided is a manufacturing method of a grain-oriented electrical steel sheet including preparing a hot-rolled sheet by hot-rolling a slab; removing some of scales formed on the hot-rolled sheet and leaving a scale layer having a thickness of 10 nm or more to prepare a hot-rolled sheet on which the scale layer remains; preparing a cold-rolled sheet by cold-rolling the hot-rolled sheet on which the scale layer remains; preparing the decarburization annealed cold-rolled sheet by decarburization annealing the cold-rolled sheet; coating an annealing separator on the decarburization annealed cold-rolled sheet to form a metal oxide layer; and final annealing the steel sheet on which the metal oxide layer is formed, wherein the annealing separator includes magnesium oxide (MgO) or magnesium hydroxide (MgOH) and fluoride.
1. A grain-oriented electrical steel sheet comprising:
a grain-oriented electrical steel sheet substrate;
a scale layer positioned on the grain-oriented electrical steel sheet substrate, the scale layer having a thickness of 5 to 100 nm; and
a metal oxide layer positioned on the scale layer,
wherein the metal oxide layer includes a forsterite compound, and
F content of the metal oxide layer is 0.1 to 3 wt %.
2. The grain-oriented electrical steel sheet of claim 1 , wherein:
the metal oxide layer includes a first phase including a forsterite compound and second phase consisting of Si, and
the first phase is included in more than 5 area % and less than 95 area % with respect to 100 area % of the metal oxide layer, and the second phase is included in more than 3 area % and less than 20 area % with respect to 100 area % of the metal oxide layer.
3. The grain-oriented electrical steel sheet of claim 1 , further comprising:
an insulation coating layer positioned on the metal oxide layer.
4. The grain-oriented electrical steel sheet of claim 1 , wherein:
the metal oxide layer includes magnesium oxide (MgO) of 1.0 wt % or less.
5. The grain-oriented electrical steel sheet of claim 1 , wherein:
the scale layer includes Si of 1 to 80 wt % and O of 1 to 80 wt %, and the balance of Fe and inevitable impurities.