Abstract: In accordance with one aspect of the present disclosure, there is provided a steel material for a tailor-welded blank, including 0.04 to 0.06 wt % of carbon (C), 1.2 to 1.5 wt % of manganese (Mn), 0.01 to 0.10 wt % of titanium (Ti), 0.01 to 0.10 wt % of niobium (Nb), and the balance of iron (Fe) and inevitable impurities; having a tensile strength (TS) of 550 MPa or greater, a yield strength (YS) of 300 MPa or greater, and an elongation (EL) of 20% or greater; and having a dual-phase structure of ferrite and martensite.

Abstract: In accordance with one aspect of the present disclosure, there is provided a steel material for a tailor-welded blank, including 0.04 to 0.06 wt % of carbon (C), 1.2 to 1.5 wt % of manganese (Mn), 0.01 to 0.10 wt % of titanium (Ti), 0.01 to 0.10 wt % of niobium (Nb), and the balance of iron (Fe) and inevitable impurities; having a tensile strength (TS) of 550 MPa or greater, a yield strength (YS) of 300 MPa or greater, and an elongation (EL) of 20% or greater; and having a dual-phase structure of ferrite and martensite.

Abstract: A steel sheet for hot stamping includes an amount of 0.17 wt % to 0.25 wt % of carbon (C), an amount of 0.3 wt % to 1.0 wt % of silicon, an amount of 0.6 wt % to 1.0 wt % of manganese (Mn), an amount of 0.02 wt % or less of phosphorus (P), an amount of 0.01 wt % or less of sulfur (S), an amount of 0.1 wt % to 1.0 wt % of aluminum (Al), an amount of 0.001 wt % to 0.005 wt % of boron (B), an amount of 0.01 wt % to 0.1 wt % of titanium (Ti), an amount of 0.02 wt % to 0.06 wt % of niobium (Nb), an amount of 0.3 wt % to 1.0 wt % of a sum of at least one of chromium (Cr), nickel (Ni), and molybdenum (Mo), and the balance of iron (Fe) and other unavoidable impurities; and also a microstructure including ferrite and pearlite.

Abstract: Provided is a hot-stamped part including a base steel sheet, the base steel sheet including an amount of about 0.19 to about 0.25 wt % of carbon (C), an amount of about 0.1 to about 0.6 wt % of silicon (Si), an amount of about 0.8 to about 1.6 wt % of manganese (Mn), an amount of about 0.03 wt % or less of phosphorus (P), an amount of about 0.015 wt % or less of sulfur (S), an amount of about 0.1 to about 0.6 wt % of chromium (Cr), an amount of about 0.001 to about 0.005 wt % of boron (B), an amount of about 0.1 wt % or less of an additive, remaining iron (Fe), and other unavoidable impurities. In an indentation strain rate with respect to an indentation depth of about 200 nm to about 600 nm is observed in a nano indentation test, a number of indentation dynamic strain aging (DSA) is about 26 to about 40.

Abstract: A method for producing a molded article includes the steps of: preparing a first steel plate and a second steel plate. The first steel plate and the second steel plate are joined to each other, thereby preparing a joined steel plate. The joined steel plate is heated at a temperature between 910° C. and 950° C. The heated joined steel plate is then subjected to hot-press molding, thereby preparing an intermediate molded article; and cooling the intermediate molded article, wherein the first steel plate has a tensile strength (TS) higher than that of the second steel plate.

Abstract: A method for manufacturing a hot-stamped part includes reheating a steel slab at a temperature of 1,200° C. to 1,250° C., the steel slab including, by wt %, 0.20 to 0.50% carbon (C), 0.05 to 1.00% silicon (Si), 0.10 to 2.50% manganese (Mn), more than 0% and not more than 0.015% phosphorus (P), more than 0% and not more than 0.005% sulfur (S), 0.05 to 1.00% chromium (Cr), 0.001 to 0.009% boron (B), 0.01 to 0.09% titanium (Ti), and a balance of iron (Fe) and inevitable impurities; finish-rolling the reheated steel slab at a temperature of 880° C. to 950° C.; cooling the hot-rolled steel plate without using water, and coiling the cooled steel plate at a temperature of 680° C. to 800° C. to form a hot-rolled decarburized layer on a surface of the steel plate; pickling the coiled steel plate, followed by cold rolling; annealing the cold-rolled steel plate in a reducing atmosphere; plating the annealed steel plate; and hot-stamping the plated steel plate.

Abstract: In accordance with one aspect of the present disclosure, there is provided a steel material for a tailor-welded blank, including 0.04 to 0.06 wt % of carbon (C), 1.2 to 1.5 wt % of manganese (Mn), 0.01 to 0.10 wt % of titanium (Ti), 0.01 to 0.10 wt % of niobium (Nb), and the balance of iron (Fe) and inevitable impurities; having a tensile strength (TS) of 550 MPa or greater, a yield strength (YS) of 300 MPa or greater, and an elongation (EL) of 20% or greater; and having a dual-phase structure of ferrite and martensite.

Abstract: In accordance with one aspect of the present disclosure, there is provided a steel material for a tailor-welded blank, including 0.04 to 0.06 wt % of carbon (C), 1.2 to 1.5 wt % of manganese (Mn), 0.01 to 0.10 wt % of titanium (Ti), 0.01 to 0.10 wt % of niobium (Nb), and the balance of iron (Fe) and inevitable impurities; having a tensile strength (TS) of 550 MPa or greater, a yield strength (YS) of 300 MPa or greater, and an elongation (EL) of 20% or greater; and having a dual-phase structure of ferrite and martensite.

Abstract: A method for manufacturing a hot-stamped part includes reheating a steel slab at a temperature of 1,200° C. to 1,250° C., the steel slab including, by wt %, 0.20 to 0.50% carbon (C), 0.05 to 1.00% silicon (Si), 0.10 to 2.50% manganese (Mn), more than 0% and not more than 0.015% phosphorus (P), more than 0% and not more than 0.005% sulfur (S), 0.05 to 1.00% chromium (Cr), 0.001 to 0.009% boron (B), 0.01 to 0.09% titanium (Ti), and a balance of iron (Fe) and inevitable impurities; finish-rolling the reheated steel slab at a temperature of 880° C. to 950° C.; cooling the hot-rolled steel plate without using water, and coiling the cooled steel plate at a temperature of 680° C. to 800° C. to form a hot-rolled decarburized layer on a surface of the steel plate; pickling the coiled steel plate, followed by cold rolling; annealing the cold-rolled steel plate in a reducing atmosphere; plating the annealed steel plate; and hot-stamping the plated steel plate.

Abstract: A method for producing a molded article includes the steps of: preparing a first steel plate and a second steel plate. The first steel plate and the second steel plate are joined to each other, thereby preparing a joined steel plate. The joined steel plate is heated at a temperature between 910° C. and 950° C. The heated joined steel plate is then subjected to hot-press molding, thereby preparing an intermediate molded article; and cooling the intermediate molded article, wherein the first steel plate has a tensile strength (TS) higher than that of the second steel plate.

Abstract: Disclosed is a high-strength hot-rolled plated steel sheet capable of suppressing material deterioration at the time of plating, while having high strength, and a method for manufacturing the same. The high-strength hot-rolled plated steel sheet may include: a hot-rolled steel sheet base material composed of 0.03-0.1 wt % of C, below 0.06 wt % of Si, 0.7-2.0 wt % of Mn, below 0.02 wt % of P, below 0.01 wt % of S, 0.1-0.5 wt % of one or more precipitate forming elements, 0.3-1.0 wt % of Al, 0.1-0.5 wt % of Mo, Fe, and unavoidable impurities; and a plated layer formed on the surface of the hot-rolled steel sheet base material.