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: 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: Disclosed is a ferritic stainless steel with reduced grain boundary erosion. A ferritic stainless steel with reduced grain boundary erosion according to an embodiment includes, in percent by weight (wt %), 0.005 to 0.1% of C, 0.01 to 1.0% of Si, 0.01 to 1.5% of Mn, 13 to 18% of Cr, 0.005 to 0.1% of N, 0.005 to 0.2% of Al, 0.005 to 0.1% of Ni, 0.003% or less of Mo, 0.05% or less of P, 0.005% or less of S, and the remainder being Fe and impurities, and satisfies an Acl, defined by Formula (1) below, of 900 or more and 990 or less: Ac1=36Cr+90Si+76Mo+760Al+350?(800C+1300N+150Ni+50Mn)??Formula (1): (wherein C, N, Si, Mn, Cr, Ni, Al, Mn, and Mo represent a content (wt %) of each element).

Abstract: The present disclosure relates to a lens that can be used for a hologram, an augmented/virtual reality display, and the like, and more particularly, to a meta-lens using a meta surface.

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: 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: 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: 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: A steel sheet for porcelain enamel according to an embodiment of the present invention comprises 0.0005 to 0.0030 wt % of C, 0.15 to 0.55 wt % of Mn, to 0.03 wt % of S, 0.0001 to 0.002 wt % of Al, 0.001 to 0.020 wt % of P, 0.001 to 0.030 wt % of S, 0.02 to 0.06 wt % of Cu, 0.005 to 0.012 wt % of N, 0.05 to 0.20 wt % of Cr, and 0.03 to 0.06 wt % of O, with the balance being Fe and inevitable impurities. A cold-rolled steel sheet for porcelain enamel according to an embodiment of the present invention comprises an oxide layer that extends inward from the surface, wherein the thickness of the oxide layer is 0.006-0.030 ?m.

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 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: 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: 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: 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 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: 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: A variable die according to an embodiment of the present invention may comprise: a first lower die part; and a first upper die part disposed above the first lower die part, wherein: the first lower die part comprises a first lower die center part and a first lower die side part; the first lower die center part includes a first sensor unit which measures a distance; a first lower die side part includes an inner member having a slope, and a drive unit which moves the inner member toward the first lower die center part; the first sensor unit measures a forming distance which is the distance from the first sensor unit to a material; and the driver unit is driven on the basis of the forming distance to adjust a correction distance which is the moving distance of the inner member.

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.