Abstract: This specification discloses a stainless steel for a fuel cell separator with excellent through-plane electrical conductivity and corrosion resistance. Disclosed a stainless steel for a fuel cell separator with excellent through-plane electrical conductivity and corrosion resistance, when the surface of stainless steel containing 15% or more of Cr by weight is measured by X-ray angle-resolved photoelectron spectroscopy using an Al-K? X-ray source under the condition that the photoelectron take-off angle is 12°, following surface oxide element ratio (1) value may be 0.5 to 5, and following surface oxide element ratio (2) value may be 0.

Abstract: The present invention relates to a high-strength hot-dipped galvanized steel sheet having excellent surface quality and spot weldability and a method for manufacturing same. The hot-dipped galvanized steel sheet according to one aspect of the present invention comprises a base steel sheet and a hot-dipped galvanized layer formed on the surface of the base steel sheet, in which an inhibiting layer made of an Fe—Al alloy can be formed at an area ratio of 60% or more between the base steel sheet and the hot-dipped galvanized layer.

Abstract: A grain oriented electrical steel sheet, according to one embodiment of the present invention, comprises: linear grooves formed on one surface or both surfaces of the electrical steel sheet in the direction (X1 direction) crossing a rolling direction; and punctuated grooves formed on one surface or both surfaces of the electrical steel sheet so as to be arranged in the direction (X2 direction) crossing the rolling direction, wherein the plurality of linear grooves and the plurality of punctuated grooves are formed in the rolling direction, and an interval (D3) between the punctuated grooves with respect to an arrangement direction (X2 direction) of the punctuated grooves is 0.02 to 1.7 times the interval (D2) between the punctuated grooves with respect to the rolling direction.

Abstract: According to an aspect of the present invention, an extremely thick steel plate for steam drum having excellent surface quality and lamellar tear resistance and a manufacturing method therefor may be provided.

Abstract: A non-oriented electrical steel sheet according to an exemplary embodiment of the present invention includes, by wt %: 2.5 to 3.8% of Si, 0.1 to 1.5% of Al, 0.1 to 2.0% of Mn, 0.01 to 0.15% of Cr, and a balance of Fe and inevitable impurities, wherein the non-oriented electrical steel sheet satisfies the following Expression 1. [Cr]>([Al]+[Mn])/[Si]/10??[Expression 1] (In Expression 1, [Cr], [Al], [Mn], and [Si] represent contents (wt %) of Cr, Al, Mn, and Si, respectively.

Abstract: Provided is a hot press-formed member having excellent crack propagation resistance and ductility. The hot press-formed member includes: a base steel sheet and a zinc or zinc alloy plating layer on at least one surface of the base steel sheet. The base steel sheet contains, by wt %, carbon (C): 0.08-0.30%, silicon (Si): 0.01-2.0%, manganese (Mn): 3.1-8.0%, aluminum (Al): 0.001-0.5%, phosphorus (P): 0.001-0.05%, sulfur (S): 0.0001-0.02%, nitrogen (N): 0.02% or less, and a balance of iron (Fe) and other impurities. The hot press-formed member comprises 1-30 area % of retained austenite as a microstructure, and a Mn(wt %)/Zn(wt %) content ratio in an oxide layer of 0.5-1.2 ?m in a thickness direction from a surface layer of the plating layer is 0.1 or more.

Abstract: One embodiment of the present invention provides a carbon filament wire for laser welding of a steel sheet having an aluminum-based coating layer, a laser welding method of a steel sheet having an aluminum-based coating layer by using same, and a welded product produced by same, the carbon filament wire comprising: a resin matrix; and two or more carbon filaments provided inside the resin matrix.

Abstract: The present invention provides a correction steel sheet for quickly and accurately correcting the sensitivity of a sensor during hardness measurement in which a sudden signal change does not occur. In one embodiment, the correction steel sheet is a steel sheet having a long side and a short side and is used for correcting a sensor and includes a first part having a first hardness and a second part having a second hardness greater than the first hardness. The first part and the second part are arranged at different positions in a short side direction, and have phases changed from austenite grains of the same composition.

Abstract: The steel sheet for plating according to an aspect of the present invention has a GDS profile of an Mn element, as observed in the depth direction from the surface, sequentially including a maximum point and a minimum point, wherein a difference of converted concentration of Mn may be 80% or more, and a difference of converged concentration of Si may be 50% or more.

Abstract: A cold-rolled steel sheet having excellent processability according to an exemplary embodiment of the present invention contains, by wt %: 0.012 to 0.060% of C, 0.03% or less (excluding 0%) of Si, 0.1 to 0.4% of Mn, 0.015 to 0.050% of Al, 0.015% or less (excluding 0%) of P, 0.015% or less (excluding 0%) of S, 0.006% or less (excluding 0%) of N, and a balance of Fe and other unavoidable impurities.

Abstract: According to one aspect of the present invention, a hot-rolled steel sheet and a manufacturing method for same may be provided, wherein the hot-rolled steel sheet has excellent yield strength, vibration damping ratio, and low-temperature toughness, and thus has physical properties suitable for use in a hyper train tube.

Abstract: One embodiment of the present invention provides: a high toughness high carbon cold rolled steel sheet having excellent formability comprising, by weight %, C: 0.80% to 1.25%, Mn: 0.2% to 0.6%, Si: 0.01% to 0.4%, P: 0.005% to 0.02%, S: 0.01% or less, Al: 0.01% to 0.1%, Cr: 0.01% to 1.0%, Sn: 0.05% to 0.5%, the remainder being Fe and other unavoidable impurities, in which a microstructure includes, by area %, retained austenite: 1% to 10%, martensite: 1% to 10%, ferrite: 5% or less (including 0%), the remainder being bainite, and has an average grain size of 3 ?m to 20 ?m, and an internal oxide layer formed directly below the surface has a thickness of 10 ?m or less; and a method for manufacturing same.

Abstract: Disclosed is a high-strength austenitic stainless steel with improved low-temperature toughness in a hydrogen environment. The austenitic stainless steel with improved low-temperature toughness in a hydrogen environment includes, in percent by weight (wt %), 0.1% or less of C, 1.5% or less of Si, 0.5 to 3.5% of Mn, 17 to 23% of Cr, 8 to 14% of Ni, 0.15 to 0.3% of N, and the balance of Fe and impurities, and optionally further includes at least one of 2% or less of Mo, 0.2 to 2.5% of Cu, 0.05% or less of Nb, and 0.05% or less of V, and the number of precipitates having an average diameter of 30 to 1000 nm and distributed in a microstructure is 20 or less per 100 ?m2.

Abstract: According to one aspect of the present invention, a hot-rolled steel sheet and a manufacturing method for same may be provided, wherein the hot-rolled steel sheet has excellent yield strength, vibration damping ratio, electrical resistivity, and low-temperature toughness, and thus has properties suitable for use in a hyper train tube.

Abstract: Provided according to one embodiment of the present invention are a non-magnetic steel material and a method for manufacturing the same. The steel material comprises 15-27 wt % of manganese, 0.1-1.1 wt % of carbon, 0.05-0.50 wt % of silicon, 0.03 wt % or less (0% exclusive) of phosphorus, 0.01 wt % or less (0% exclusive) of sulfur, 0.050 wt % or less (0% exclusive) of aluminum, 5 wt % or less (0% inclusive) of chromium, 0.01 wt % or less (0% inclusive) of boron, 0.1 wt % or less (0% exclusive) of nitrogen, and a balance amount of Fe and inevitable impurities, has an index of sensitivity of 3.4 or less, the index of sensitivity being represented by the following relational expression (1): [Relational expression 1]?0.451+34.131*P+111.152*Al?799.483*B+0.526*Cr?3.4 (wherein [P], [Al], [B] and [Cr] each mean a wt % of corresponding elements), and contains a microstructure with austenite at an area fraction of 95% or greater therein.

Abstract: Provided is a hot-dip galvanized steel sheet used for an automobile outer panel and so forth and, more specifically, to a method for producing a hot-dip galvanized steel sheet having excellent press formability and clarity after painting, and to a hot-dip galvanized steel sheet produced by the method.

Abstract: According to one aspect of the present invention, a high-strength hot-dip galvanized steel sheet having an excellent surface quality and spot weldability, and a manufacturing method therefor may be provided.

Abstract: An exemplary embodiment of the present invention provides an enamel steel sheet, including: by wt % (% by weight), 0.01 to 0.05% of C, 0.05 to 0.8% of Mn, 0.001 to 0.03% of Si, 0.03 to 0.12% of Al, 0.001 to 0.02% of P, 0.001 to 0.02% of S, 0.004% or less (excluding 0%) of N, 0.001 to 0.003% of B, 0.003% or less (excluding 0%) of O, and the balance of Fe and inevitable impurities. The enamel steel sheet according to an exemplary embodiment of the present invention includes an oxide layer in an inside direction from a surface, and a thickness of the oxide layer is 0.006 to 0.030 ?m.

Abstract: An embodiment of the present invention provides a method for manufacturing a tailor welded blank using a steel sheet for hot pressing having an Al-Fe-based intermetallic alloy layer, the method comprising the steps of: preparing a plated steel sheet having a base steel sheet and an aluminum-based plated layer formed on one surface or both surfaces of the base steel sheet; heat-treating the plated steel sheet so that the aluminum-based plated layer becomes an Al-Fe-based intermetallic alloy layer; and subjecting the heat-treated plated steel sheet to butt welding, wherein, before the welding, a part or the entirety of the Al-Fe-based intermetallic alloy layer located in an area to be welded is removed.

Abstract: The present invention relates to a hot press formed member. A hot press formed member according to one aspect of the present invention comprises a steel sheet; and a plating layer on the steel sheet, wherein a number of voids per 1000 ?m2 of an area from an interface between the plating layer and the steel sheet to 15 ?m is zero and wherein a concentration gradient at a section having an Fe content of 45% to 80% in the plating layer in a thickness direction from a surface of the plating layer according to a result of GDS analysis is 7 wt %/?m or less.