Posco Co., Ltd

Woo-Sin Kim

Jong-Tae Park

Oh-Yeoul Kwon

Chang Soo Park

Hyung Don Joo

Hyun-Chul Park

Kyu-Seok Han

Jae Kyoum Kim

Won-Gul Lee

Chang-Ho Kim

Oho-Cheal Kwon

Dae-Uk Kim

An embodiment of the present invention provides a grain-oriented electrical steel sheet, including a groove including a bottom portion and a side portion positioned on a surface of the electrical steel sheet, a metal oxide layer positioned on the groove, and an insulating layer positioned on the metal oxide layer, wherein the steel sheet includes a normal groove in which thicknesses of the metal oxide layer positioned on the bottom portion and the side portion exceed 0.5 μm, and a defective groove in which thicknesses of the metal oxide layer positioned on the bottom portion and the side portion are 0.5 μm or less, the insulating layer positioned on the normal groove has a thickness of 0.5 μm to 1.5 μm, and the insulating layer positioned on the defective groove has a thickness of 1.5 to 10 μm.

Oriented electrical steel sheet and method for manufacturing same

A manufacturing method of a grain-oriented electrical steel sheet according to an embodiment of the present invention includes: manufacturing a cold-rolled sheet; forming a groove in the cold-rolled sheet; removing an Fe—O oxide formed on a surface of the cold-rolled sheet; primary recrystallization annealing the cold-rolled sheet; and applying an annealing separating agent to the primary recrystallized cold-rolled sheet, and secondary recrystallization annealing it, wherein a close contacting property coefficient calculated by Formula 1 below is 0.016 to 1.13.close contacting property coefficient ()=(0.8×)/  [Formula 1] (In Formula 1, R represents the average roughness (μm) of the surface of the cold-rolled sheet after the removing of the oxide, and Hrepresents the average height (μm) of the hill-up present on the surface of the cold-rolled sheet after the removing of the oxide.).

Grain-oriented electrical steel sheet and manufacturing method therefor

A manufacturing method of a grain-oriented electrical steel sheet according to an embodiment of the present invention, includes: manufacturing a cold-rolled sheet; forming a groove by irradiating a laser beam on the cold-rolled sheet; and partially removing an oxide layer formed on a surface of the cold-rolled sheet so that a thickness of the oxide layer remains at 1 to 5 nm, wherein the grain-oriented electrical steel sheet has islands of 0.25 or less having sphericity of 0.5 to 0.9 under the oxide layer under the groove.

Oriented electrical steel sheet and method for producing same

A grain-oriented electrical steel sheet of an embodiment of the present invention comprises Si: 1.0% to 7.0% and Y: 0.005% to 0.5% by wt %, and the remainder comprising Fe and other inevitable impurities, and 10 pieces or less of inclusions comprising Y and having a diameter of 30 nm to 5 &#x3bc;m per area of 1 mm.

Growing community of inventors

Pohang-si, South Korea

Woo-Sin Kim