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.

An object of the present invention is to provide magnesium oxide for an annealing separator which is useful for obtaining grain-oriented electromagnetic steel sheets with excellent magnetic properties and insulating properties. To resolve the above object, an aspect of the present invention resides in magnesium oxide for an annealing separator which has a BET specific surface area of 12.0×10.sup.3 to 25.0×10.sup.3 m.sup.2.Math.kg.sup.−1 and a Blaine specific surface area of 2.0×10.sup.3 to 7.0×10.sup.3 m.sup.2.Math.kg.sup.−1.

Provided herein is a dual-phase stainless steel having excellent carbon dioxide corrosion resistance, excellent sulfide stress corrosion cracking resistance, and excellent sulfide stress cracking resistance. The dual-phase stainless steel contains, in mass %, C: 0.03% or less, Si: 1.0% or less, Mn: 0.10 to 1.5%, P: 0.030% or less, S: 0.005% or less, Cr: 20.0 to 30.0%, Ni: 5.0 to 10.0%, Mo: 2.0 to 5.0%, Cu: 2.0 to 6.0%, N: less than 0.07%, and the balance Fe and unavoidable impurities, and has a structure that is 20 to 70% austenite phase, and 30 to 80% ferrite phase in terms of a volume fraction.

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 according to one preferred aspect of the present invention are austenitic steel material having superb abrasion resistance and toughness, and a method for producing the austenite steel material. The austenitic steel material having superb abrasion resistance and toughness according to one preferred aspect of the present invention comprises, in wt %, 0.6-1.9% carbon (C); 12-22% manganese (Mn); 5% or lower (excluding 0%) chromium (Cr); 5% or lower (excluding 0%) copper (Cu); 0.5% or lower (excluding 0%) aluminum (Al); 1.0% or lower (excluding 0%) silicon (Si); 0.1% or lower (including 0%) phosphorous (P); 0.02% or lower (including 0%) sulfur (S); and the rest in Fe and unavoidable impurities, and has the microstructure comprising, by surface area fraction, 97% or higher (including 100%) austenite and 3% or lower (including 0%) carbide.

A non-oriented electrical steel sheet according to one embodiment of the invention has a chemical composition represented by C: 0.0030% or less, Si: 2.00% or less, Al: 1.00% or less, Mn: 0.10% to 2.00%, S: 0.0030% or less, one or more selected from the group consisting of Mg, Ca, Sr, Ba, Nd, Pr, La, Ce, Zn, and Cd: 0.0003% or greater and less than 0.0015% in total, a parameter Q represented by Q=[Si]+2×[Al]−[Mn]: 2.00 or less; Sn: 0.00% to 0.40%, Cu: 0.00% to 1.00%, and a remainder: Fe and impurities, and a parameter R represented by R−(I.sub.100+I.sub.310+I.sub.411+I.sub.521)/(I.sub.111+I.sub.211+I.sub.332+I.sub.221) is 0.80 or greater.

Provided is a rail that is effective in improving wear resistance and rolling contact fatigue (RCF) resistance. The rail has a metallic structure including a pearlitic structure and a structure other than the pearlitic structure in a surface layer from a surface of a rail head to a depth of at least 0.5 mm, where the pearlitic structure has Vickers hardness of 420 HV or more and 520 HV or less, and the structure other than the pearlitic structure has Vickers hardness of 350 HV or more and 420 HV or less.

A non-oriented electrical steel sheet according to an embodiment of the present invention includes, in wt%, Si: 2.2 to 4.5 %, Mn: 0.5 % or less (excluding 0 %), AI: 0.001 to 0.5 %, Sn: 0.07 to 0.25 %, and N: 0.0010 to 0.0090 %, and the balance of Fe and inevitable impurities.

A surface layer portion existing in an inner direction from a surface of the steel sheet and a central portion existing inside the surface layer portion are included, and the central portion includes N at 0.005 wt% or less, and the surface layer portion further includes N at 0.001 wt% or more compared to the central portion; and the surface layer portion has an average grain size of 60 .Math.m or less, while the central portion has an average grain size of 70 to 300 .Math.m.

Disclosed are high-strength ferritic stainless steel STS430, which has a yield strength of 350 MPa or greater and can be applied to a clamp of a vehicle or a common hose, and a manufacturing method thereof. The high-strength ferritic stainless steel for a clamp, according to one embodiment of the present invention, comprises, by weight, 0.04-0.1% of C, 0.2-0.6% of Si, 0.01-1.5% of Mn, 14.0-18.0% of Cr, 0.005-0.2% of Al, 0.005-0.2% of V, 0.02-0.1% of N, and the remainder as Fe and inevitable impurities, satisfies Expressions (1) and (2), and has at least 2.5×10.sup.6 precipitates having a mean diameter of 0.5 μm or less per mm.sup.2. (1) 0.35%≤Si+Al+V≤0.6% (2) 0.09%≤C+N≤0.12%