Abstract: The present exemplary embodiments relate to a positive electrode active material, its manufacturing method, and a lithium secondary battery including the same. The positive electrode active material according to an exemplary embodiment is a metal oxide particle including: a metal oxide particle comprising a central portion and a surface portion located on the surface of the central portion, wherein, the metal oxide particle includes nickel, cobalt, manganese, and doping elements and is composed of a single particle, and the metal oxide particle includes a crystal phase of layered structure belonging to the R-3m space group on the surface, and an average grain size is 1550 ? or more.

Abstract: The present invention relates to a steel material used as materials for building structures, ship structures, offshore structures, or the like and, more specifically, to a steel material having low yield ratio and excellent weld heat affected zone toughness and a manufacturing method therefor.

Abstract: The present invention relates to technology for printing an image such as a letter, a picture, or the like on a surface of a metal material, including printing equipment capable of stably printing the image on the surface of the metal material at high speed, a printing method using the same, and a printed metal material obtained therefrom.

Abstract: The present invention relates to: a hot rolled steel sheet for ground reinforcement and a steel pipe for ground reinforcement, which have excellent strength and formability; and manufacturing methods thereof. An aspect of the present disclosure is to provide a hot-rolled steel sheet for ground reinforcement and a steel pipe for ground reinforcement, having excellent strength and formability, and manufacturing methods thereof.

Abstract: The present disclosure relates to a cold rolled steel sheet having excellent weldability, strength and formability and a method of manufacturing the same. An aspect of the present disclosure is to provide a cold-rolled steel sheet having excellent weldability, strength, and formability, and a method of manufacturing the same. As set forth above, according to an aspect of the present disclosure, a cold-rolled steel sheet having excellent weldability, strength, and formability and a method of manufacturing the same may be provided.

Abstract: The present invention provides a battery case comprising: a side frame; longitudinal members which are arranged in the side frame and extend in the longitudinal direction; width-direction members which are arranged in the side frame and extend in the width-direction so as to be connected crosswise with the longitudinal members, and which each include a first lower width-direction unit and a second lower width-direction unit that are arranged overlapping in the height direction; and a cooling panel which is arranged above the first lower width-direction units and cools a battery module.

Abstract: The present invention relates to a discharge method of a battery, comprising: a first discharging step of discharging a battery by connecting the battery and a power converter and applying voltage thereto; and a second discharging step of discharging the battery by applying a reverse voltage of the voltage of the first discharging step, after the first discharging step. According to the present invention, electrical energy of a battery can be recovered and recycled, and an electrically safe state can be secured in a subsequent disassembly process by putting the battery in a completely discharged state in which normal operation is impossible.

Abstract: The present invention provides a seat frame comprising: a cushion part for supporting a cushion; a height-adjusting part which is provided below the cushion part, and which adjusts the height of the cushion part by means of a plurality of rotary links; a rotating part which is provided below the height-adjusting part, and which rotates the height-adjusting part and the cushion part; and reinforcing bracket parts which are coupled to the lower side of the rotating part so as to reinforce the rotating part, and which are provided over a pair of rails of a rail part arranged below same so as to be spaced apart.

Abstract: An embodiment of the present invention provides a hot-rolled steel sheet comprising, by wt %, 0.06-0.12% of C, 0.004-0.4% of Si, 0.8-2.0% of Mn, 0.01-0.05% of Al, 0.05-1.0% of Cr, 0.001-0.3% of Mo, 0.001-0.05% of P, 0.001-0.005% of S, 0.001-0.01% of N, 0.001-0.05% of Nb, 0.001-0.05% of Ti, 0.001-0.005% of B, and the remainder of Fe and other inevitable impurities, satisfying relational formula 1 below, and having a microstructure including, by area, 80% or more of auto-tempered martensite, and a remainder of at least one of fresh martensite, bainite, and ferrite. [Relational formula 1] (10[C]+[Si]+2.5[Mn])/(1.5[Cr]+2.0[Mo]?3.

Abstract: The present invention relates to a graphite steel having excellent machinability, and a manufacturing method therefor, and more specifically, to a calcium-containing graphite steel having machinability superior to that of normal free-cutting steel and a manufacturing method therefor.

Abstract: Provided is a plated steel sheet and a method for manufacturing the same, and more particularly, to a zinc-based plated steel sheet having high strength and high formability that may be suitably applied as a material for an automotive outer panel and a method for manufacturing the same.

Abstract: One aspect of the present invention provides a method for preventing spot welding crack of a galvanized steel plate, which can reduce crack occurring due molten zinc having a low melting point when a galvanized advanced high strength steel (AHSS) plate is spot-welded, and can thus improve welding strength and fatigue life.

Abstract: The present invention relates to a surface treatment composition comprising, on the basis of 100 wt % of the solid part of the composition, 20-40 wt % of a water-soluble polyurethane resin, 40-60 wt % of a silane-based sol-gel resin in which three types of silane compounds are cross-linked, 5-15 wt % of a curing agent, 0.5-1.5 wt % of a corrosion inhibitor, 0.1-1.0 wt % of a molybdenum-based compound, 1.0-3.0 wt % of a silane coupling agent; 1.0-2.0 wt % of an organometallic complex, 1.0-2.0 wt % of an acid scavenger, 0.1-1.0 wt % of an aluminum-based compound, and 1.0-2.0 wt % of a lubricant. A ternary hot-dip galvannealed steel sheet treated with a chromium-free surface treatment coating agent, according to an exemplary embodiment in the present invention, has excellent resistance to blackening, alkali and corrosion, and provides excellent effects without concern for problems, in chromium treatment, of additional equipment installation, an increase in manufacturing costs and environmental pollution.

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 Fe3Al, FeAl(Si), Fe2Al5, and FeAl3; 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: 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.

Abstract: The present invention relates to an ultra-high strength cold-rolled steel sheet and a manufacturing method thereof and, more specifically, to a cold-rolled steel sheet and a manufacturing method thereof, wherein the cold-rolled steel sheet has a tensile strength of 1.5 GPa and exhibits an excellent elongation rate, and as such, can be suitably used for cold stamping.

Abstract: The present invention related to a structural steel sheet having excellent seawater resistance and having excellent corrosion resistance in environments in which corrosion is accelerated by seawater, and a method for manufacturing same.

Abstract: A galvanized steel sheet according to one aspect of the present invention comprises: a base steel sheet; and a Zn—Al—Mg-based plating layer provided on at least one surface of the base steel sheet, wherein the Zn—Al—Mg-based plating layer may include a surface modified region enriched with cerium (Ce) on a surface layer side of the Zn—Al—Mg-based plating layer.

Abstract: The present invention provides a steel material, and a method of manufacturing the same. The steel material comprises, by weight %, 0.02 to 0.07% of carbon, 0.1 to 0.5% of silicon, 0.2 to 0.7% of manganese, 0.05% or less of phosphorus, 0.02% or less of sulfur, 0.07% or less of aluminum, 0.1 to 0.5% of chromium, 0.3 to 1.0% of molybdenum, 0.05% or less of vanadium, 50 ppm or less of boron, 0.01 to 0.5% of nickel, 0.5% or less of copper, 0.02% or less of titanium, 0.05% or less of niobium, and 2 to 100 ppm of calcium, and the balance of Fe and other unavoidable impurities, and satisfies relational expressions 1 and 2 mentioned below, wherein the microstructure thereof contains, by area %, 90% or more of martensite and 10% or less of bainite. 260?1589×[C]+228?340??[Relational Expression 1] [C]/[Mo]?0.

Abstract: The present invention relates to a steel material to which post weld heat treatment (PWHT) is applied after pipe making and, more specifically, to a steel material that maintains excellent low-temperature toughness even after undergoing a PWHT process, a steel material which is obtained therefrom, and which has undergone PWHT, and a method for manufacturing the same.