Abstract: The present invention relates to a zinc plated steel sheet having excellent surface quality and spot weldability, and a manufacturing method therefore. A zinc plated steel sheet according to one aspect of the present invention comprises a base steel sheet and a zinc-based plating layer formed on the surface of the base steel sheet, wherein the GDOES profile of oxygen, which is measured in the depth direction from the surface of the base steel sheet, has a form in which a local minimum point and a local maximum point alternately appear in the depth direction from the surface, and the difference (a local maximum value?a local minimum value) between the oxygen concentration (a local minimum value) at the local minimum point and the oxygen concentration (a local maximum value) at the local maximum point can be 0.1 wt % or more.

Abstract: The present invention relates to a high-strength steel sheet having excellent surface quality due to improved coatability thereof and a method for manufacturing same.

Abstract: Disclosed are a ultrafine austenitic stainless steel simultaneously satisfying a high strength, a high elongation, and a high yield ratio and a method for manufacturing the same. An austenitic stainless steel according to an embodiment of the present disclosure includes, in percent by weight (wt %), 0.005 to 0.03% of carbon (C), 0.1 to 1.0% of silicon (Si), 0.1 to 2.0% of manganese (Mn), 6.0 to 12.0% of nickel (Ni), 16.0 to 20.0% of chromium (Cr), 0.01 to 0.2% of nitrogen (N), 0.25% or less of niobium (Nb), and the balance of iron (Fe) and inevitable impurities, wherein a thickness central region has an average grain size d of 5 ?m or less, and a fraction of a unrecrystallized area in a band form is 10% or less.

Abstract: The present invention provides a plated steel sheet excellent in corrosion resistance and excellent in at least one of weldability and phosphatability, and a manufacturing method therefor. And more specifically, the present invention provides a Zn—Mg—Al-based plated steel sheet excellent in corrosion resistance, weldability and phosphatability, and a manufacturing method therefor.

Abstract: The present invention relates to a highly thick steel material and a manufacturing method therefor and, more specifically, to a highly thick steel material that exhibits excellent low-temperature impact toughness after long-term PWHT although the steel sheet is thick, and a manufacturing method therefor.

Abstract: An aspect of the present invention relates to a high strength steel sheet having an excellent high-temperature elongation characteristic, wherein the sheet comprises, by weight %, 0.4-0.9% of C, 0.01-1.5% of Cr, 0.03% or less (exclusive of 0%) of P, 0.01% or less (exclusive of 0%) of S, 0.01% or less (exclusive of 0%) of N, 0.01% or less (exclusive of 0%) of sol. Al, and a balance of Fe and inevitable impurities, and comprises at least one among 2.1% or less (exclusive of 0%) of Mn and 1.6% or less (exclusive of 0%) of Si; the sheet has a microcrystalline structure including pearlite having an area fraction of 80% or more and ferrite having an area fraction of 20% or less; and the pearlite includes cementite having a major axis length of 200 nm or shorter.

Abstract: The present invention provides a high strength hot rolled steel sheet and a method for manufacturing same, the steel sheet containing, in weight percentage, 0.11-0.14% of C, 0.20-0.50% of Si, 1.8-2.0% of Mn, 0.03% or less of P, 0.02% or less of S, 0.01-0.04% of Nb, 0.5-0.8% of Cr, 0.01-0.03% of Ti, 0.2-0.4% of Cu, 0.1-0.4% of Ni, 0.2-0.4% of Mo, 0.007% or less of N, 0.001-0.006% of Ca, 0.01-0.05% of Al, a balance of Fe and inevitable impurities, wherein relational expressions 1 to 3 below are satisfied, and a microstructure includes, by area percentage, 88% or more of bainite, 10% or less of ferrite, 2% or less of pearlite, and 0.8% or less of island martensite. [Relational Expression 1] 7?(Mo/93)/(P/31)?16. [Relational Expression 2] 1.6?Cr+3Mo+2Ni?2. [Relational Expression 3] 6?(3C/12+Mn/55)×100?7.

Abstract: The present disclosure relates to a hot-rolled steel sheet utilized as material for heavy machinery, vehicle frames, and the like, and more specifically to a high-strength hot-rolled steel sheet having excellent bendability and low-temperature toughness and a method for manufacturing same.

Abstract: The present invention provides a Zn—Mg—Al-based plated steel sheet having excellent in corrosion resistance and whiteness, and a method for manufacturing the same. And more specifically, the present invention provides a Zn—Mg—Al-based plated steel sheet having excellent in corrosion resistance, whiteness and bendability, and a method for manufacturing the same.

Abstract: One embodiment of the present invention relates to a lithium metal anode. Wherein the lithium metal anode comprises a current collector and a lithium metal thin film layer disposed on at least one surface of the current collector and having a thickness in a range of 0.1 to 200 ?m and a coating layer disposed on a surface of the lithium metal thin film layer, wherein, the coating layer comprising a Li—N—C—H—O based ionic compound.

Abstract: The present invention provides a Zn—Mg—Al plated steel sheet having excellent in corrosion resistance and bendability, and a method for manufacturing same. And more specifically, the present invention provides a Zn—Mg—Al-based plated steel sheet having excellent in corrosion resistance, bendability, and plating adhesion, and a method for manufacturing the same.

Abstract: The present invention relates to steel suitable for a pressure vessel that can be used as petrochemical manufacturing equipment, a storage tank, and the like, and, more specifically, to steel having excellent hydrogen-induced cracking (HIC) resistance and low-temperature impact toughness and a method for manufacturing same.

Abstract: The present invention provides a cross member for a battery case. The cross member comprises: a first frame part; a second frame part; and a connection frame part arranged between the first frame part and the second frame part to connect the first frame part with the second frame part, wherein the connection frame part is made of a material different from those of the frame part and the second frame part.

Abstract: The present invention provides a shape checking device for a bending material including: a material fixing unit including a support member in which a first surface of a material including a first surface and a second surface, bent from the first surface is seated, and a pressing member configured to press the first surface of the material; and a distance measuring unit, and measuring a distance to the second surface, wherein the distance measuring unit includes a first distance measuring device for measuring a distance to the second surface, and a second distance measuring device for measuring a distance to a second surface, which is the same as the second surface on which a distance thereof is measured by the first distance measuring device, in a position, spaced apart from the first distance measuring device in a first direction, different from a bending forming direction of a material.

Abstract: The present invention relates to: a steel material having high strength and excellent impact toughness, the steel material being usable for a land wind power generator and the like; and a method for manufacturing same.

Abstract: A ferritic stainless steel with improved expandability includes, in percent (%) by weight of the entire composition, Cr: 10 to 25%, N: 0.015% or less (excluding 0), Al: 0.005 t 0.04%, Nb: 0.1 to 0.6%, Ti: 0.1 to 0.5%, the remainder of iron (Fe) and other inevitable impurities, and satisfies the following equation (1): Z=X*Y?17??equation(1).

Abstract: The present invention provides an aluminum-based plated steel plate used in hot-press forming, the steel plate comprising: a base steel plate; and a plating layer formed on the base steel plate, wherein the plating layer comprises: an alloying layer formed on the surface of the base steel plate and including one or more of Fe 3Al, FeAl(Si), Fe 2Al 5, and FeAl 3; and an aluminum layer formed on the alloying layer and having a thickness less than 10% of the thickness of the plating layer, and the plating layer has a thickness of 5-20 ?m and an oxygen content of 10 weight % or less, as measured by GDS, at a depth of 0.1 ?m from the surface of the plating layer.

Abstract: One aspect of the present invention relates to an ultrahigh-strength steel sheet having an excellent yield ratio, comprising, by wt %, 0.3-0.5% of C, 2.0% (excluding 0%) of Si, 3.0-6.5% of Mn, 0.02% or less of P, 0.01% or less of S, 0.01-3.0% of Al, 0.02% or less (excluding 0%) of N, and the balance of Fe and other inevitable impurities, and a microstructure comprises 5-30% of remaining austenite by area fraction and comprises 5% or less of secondary martensite.

Abstract: A grain-oriented electrical steel sheet according to an embodiment of the present disclosure includes: a forsterite layer formed on the surface of an electrical steel sheet; a groove which is formed on the forsterite layer in a direction perpendicular to a rolling direction; and a forsterite calcination layer which is formed in the direction of both ends of the electrical steel sheet on the basis of an upper end of the groove and has a width of 1.1 to 1.3 times the width of the groove.

Abstract: Disclosed in the present specification are steel and a steel wire, which are for a spring, and manufacturing methods therefor, the steel and the steel wire having excellent resistance to permanent deformation by having increased in-material dislocation density or reduced average grain diameter. The steel wire for a spring, having excellent resistance to permanent deformation, according to one embodiment of the present invention, comprises, by wt %, 0.4-0.7% of C, 1.2-2.3% of Si, 0.2-0.8% of Mn, 0.2-0.8% of Cr, and the balance of Fe (iron) and other inevitable impurities, wherein the dislocation density thereof can be 1.16×1015/m2 or more, and the average grain diameter thereof can be 8.4 ?m or less.