A hot-stamping formed body has a predetermined chemical composition and includes microstructure which includes residual austenite of which an area ratio is 10% or more and less than 20%, Among grain boundaries of crystal grains of bainite and tempered martensite a ratio of a length of a grain boundary having a rotation angle in a range of 55° to 75° to a total length of a grain boundary having a rotation angle in a range of 4° to 12°, a grain boundary having a rotation angle in a range of 49° to 54°, and the grain boundary having a rotation angle in, a range of 55° to 75° to the <011> direction as a rotation axis is 30% or more.

A hot-stamping formed body has a predetermined chemical composition and includes microstructure which includes residual austenite of which an area ratio is 5% or more and less than 10%. Among grain boundaries of crystal grains of bainite and tempered martensite in the microstructure, a ratio of a length of a grain boundary having a rotation angle in a range of 55° to 75° to a total length of a grain boundary having a rotation angle in a range of 4° to 12°, a grain boundary having a rotation angle in a range of 49° to 54°, and a grain boundary having a rotation angle in a range of 55° to 75° to the <011> direction as a rotation axis is 30% or more. The tensile strength of the hot-stamping formed body is 1500 MPa or more.

A method of forming a component having a cross-section with a bend radius includes providing a work-piece blank from press-hardened steel (PHS). The method also includes austenitizing the work-piece blank in a furnace via heating the strip of sheet metal to achieve therein an austenite microstructure, including soaking the work-piece blank for a predetermined amount of time. The method additionally includes quenching the austenitized work-piece blank to achieve therein a martensitic matrix microstructure with dispersed chromium-enriched carbide. The method also includes roll-forming the austenitized and quenched work-piece blank to generate the cross-section and the bend radius. The method may further include locally heating the bend radius area during the roll-forming of the cross-section to reduce an amount of chromium-enriched carbide in the martensitic matrix microstructure inside the bend radius area relative to the microstructure outside the bend, and thereby generating the component having high strength, ductility, and wear resistance.

A method of forming a component having a cross-section with a bend radius includes providing a work-piece blank from press-hardened steel (PHS). The method also includes austenitizing the work-piece blank in a furnace via heating the strip of sheet metal to achieve therein an austenite microstructure, including soaking the work-piece blank for a predetermined amount of time. The method additionally includes quenching the austenitized work-piece blank to achieve therein a martensitic matrix microstructure with dispersed chromium-enriched carbide. The method also includes roll-forming the austenitized and quenched work-piece blank to generate the cross-section and the bend radius. The method may further include locally heating the bend radius area during the roll-forming of the cross-section to reduce an amount of chromium-enriched carbide in the martensitic matrix microstructure inside the bend radius area relative to the microstructure outside the bend, and thereby generating the component having high strength, ductility, and wear resistance.

Provided is a grain-oriented electrical steel sheet having better transformer iron loss property than conventional grain-oriented electrical steel sheets. A grain-oriented electrical steel sheet comprises: a steel substrate; a forsterite film on a surface of the steel substrate; and a Cr-depleted layer at a boundary between the steel substrate and the forsterite film, the Cr-depleted layer having a Cr concentration that is 0.70 times to 0.90 times a Cr concentration of the steel substrate.

Provided is a grain-oriented electrical steel sheet having better transformer iron loss property than conventional grain-oriented electrical steel sheets. A grain-oriented electrical steel sheet comprises: a steel substrate; a forsterite film on a surface of the steel substrate; and a Cr-depleted layer at a boundary between the steel substrate and the forsterite film, the Cr-depleted layer having a Cr concentration that is 0.70 times to 0.90 times a Cr concentration of the steel substrate.

A method for manufacturing a grain-oriented electrical steel sheet according to an embodiment of the present invention comprises the steps of: hot-rolling a slab to prepare a hot-rolled sheet, the slab containing, in wt %, 2.0 to 6.0% of Si, 0.04 to 0.12% of Mn, 0.001 to 0.022% of N, 0.027 to 0.060% of C, 0.01 to 0.08% of Nb, 0.01% or less of Ti, and the balance of Fe and other inevitable impurities; cold-rolling the hot-rolled sheet to prepare a cold-rolled sheet; and subjecting the primarily recrystallization-annealed cold-rolled sheet to secondary recrystallization annealing.

A method for manufacturing a grain-oriented electrical steel sheet according to an embodiment of the present invention comprises the steps of: hot-rolling a slab to prepare a hot-rolled sheet, the slab containing, in wt %, 2.0 to 6.0% of Si, 0.04 to 0.12% of Mn, 0.001 to 0.022% of N, 0.027 to 0.060% of C, 0.01 to 0.08% of Nb, 0.01% or less of Ti, and the balance of Fe and other inevitable impurities; cold-rolling the hot-rolled sheet to prepare a cold-rolled sheet; and subjecting the primarily recrystallization-annealed cold-rolled sheet to secondary recrystallization annealing.

Provided is a steel sheet which can be used for automobile parts and the like, and relates to a steel sheet having an excellent balance of strength and ductility and an excellent balance of strength and hole expansibility, and excellent bending workability, and a method for manufacturing same.

Provided is a steel sheet which can be used for automobile parts and the like, and relates to a steel sheet having an excellent balance of strength and ductility and an excellent balance of strength and hole expansibility, and excellent bending workability, and a method for manufacturing same.