Abstract: Disclosed are a hot-rolled galvanized steel sheet having excellent galling resistance and formability, and a method for manufacturing the same. The hot-rolled galvanized steel sheet, includes: a base steel; and a hot-rolled galvanizing layer formed on the surface of the base steel, wherein the hot-rolled galvanizing layer provides a hot-rolled galvanized steel sheet having a Mn crystallite having a size of 10 ?m or less between the resin dendrites of zinc that form sequins.
Abstract: Provided is a hot-dip galvanized steel plate which is applicable as a material for a vehicle outer panel and has an excellent bake hardenability and anti-aging property at room temperature, and a method for manufacturing a hot-dip galvanized steel plate, the method comprising a process including the steps of: winding a hot-rolled steel plate, followed by cooling at a speed of 0.002-0.027° C./sec; cold-rolling the cooled steel plate; continuously annealing the cold-rolled steel plate; and cooling the annealed steel plate in the multi-stage manner of primary to third rounds.
Abstract: Provided is an ultra-high strength steel sheet having excellent phosphatability and bendability. The ultra-high strength steel sheet includes, by weight percentage (wt %), carbon (C): 0.08% to 0.2%, silicon (Si): 0.05% to 1.3%, manganese (Mn): 2.0% to 3.0%, phosphorus (P): 0.001% to 0.10%, sulfur (S): 0.010% or less, aluminum (Al): 0.01% to 0.1%, chromium (Cr): 0.3% to 1.2%, boron (B): 0.0010% to 0.0030%, titanium (Ti): 0.01% to 0.05%, nitrogen (N): 0.001% to 0.01%, a remainder of iron (Fe) and other inevitable impurities, satisfying: 3.4?Ti/N?10, 1.0?Mn/(Si+Cr), and 0.7?Mn*/(Si*+Cr*)?Mn/(Si+Cr), where Ti, N, Mn, Si and Cr refer to a weight percentage (wt %), and Mn*, Si* and Cr* refer to an average of values obtained by GDS component analysis from a surface to a 0.1 ?m position in a thickness direction.
Abstract: Provided is a high-manganese hot-dip aluminum-coated steel sheet comprising: a base steel sheet containing, by weight, 5% to 35% of Mn, 0.3 to 6% of Al, 0.1 to 1.2% of Si, the balanced amount of Fe, and inevitable impurities; a hot-dip aluminum-coated layer, formed on a surface of the base steel sheet, containing, by weight, 3 to 12% of Si and the balanced amount of Al, and inevitable impurities; and an alloy layer, 0.1 to 10 ?m in thickness with a Fe—Al—Si—Mn-based alloy phase on an interface between the base steel sheet and the hot-dip aluminum-coated layer, containing, by weight, 40 to 70% of Al, 2 to 13% of Si, 3 to 9% of Mn, the balance amount of Fe, and inevitable impurities.
Type:
Grant
Filed:
December 23, 2016
Date of Patent:
April 6, 2021
Assignee:
POSCO
Inventors:
Heung-Yun Kim, Hyeon-Seok Hwang, Young-Ha Kim
Abstract: The present invention relates to a cooling device and a cooling method capable of controlling, by section, the flow of coolant supplied in a widthwise direction, the cooling device comprising: a base frame connected to an external cooling fluid supply line, and disposed to be able to spray coolant onto a material that passes through a rolling mill after having been heated in a heating furnace; and a nozzle assembly disposed on the base frame, and spraying a cooling fluid in an arbitrary pattern onto a plurality of sections divided along the widthwise direction of the material to minimize a deviation in temperature in the widthwise direction of the material. Through this configuration, the flow of coolant supplied in the widthwise direction of a material can be controlled to be varied, thereby being capable of minimizing a deviation in temperature in the widthwise direction of a high temperature material.
Type:
Grant
Filed:
July 27, 2016
Date of Patent:
April 6, 2021
Assignee:
POSCO
Inventors:
Pil-Jong Lee, Jong-Hoon Kang, Hui-Seop Kwon, Gwan-Sik Min
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.
Type:
Grant
Filed:
December 23, 2016
Date of Patent:
March 30, 2021
Assignee:
POSCO
Inventors:
Un-Hae Lee, Sung-Kyu Kim, Soon-Gi Lee, Yong-Jin Kim, Hong-Yeol Oh
Abstract: Provided is a high tensile strength steel having a tensile strength of 780 MPa grade or higher which is used for structural members of automobiles, and more specifically relates to high tensile strength steel having excellent bendability and stretch-flangeability while still satisfying characteristics of DP steels of low yield ratio and high ductility, and to a manufacturing method thereof.
Type:
Grant
Filed:
December 7, 2017
Date of Patent:
March 9, 2021
Assignee:
POSCO
Inventors:
Yeon-Sang Ahn, Chang-Hyo Seo, Ki-Hyun Park
Abstract: Provided is a cold-rolled steel sheet, a galvanized steel sheet and a galvannealed steel sheet, comprising, by wt %, 0.06-0.15% of C, 1.2% or less (excluding 0%) of Si, 1.7-2.7% of Mn, 0.15% or less (excluding 0%) of Mo, 1.0% or less (excluding 0%) of Cr, 0.1% or less (excluding 0%) of P, 0.01% or less (excluding 0%) of S, 0.001-0.04% of Ti, 0.001-0.04% of Nb, 0.01% or less (excluding 0%) of N, 0.01% or less (excluding 0%) of B, and a remainder of Fe and unavoidable impurities, wherein the Si, C, Mn, Mo and Cr contents satisfy Relationship 1, and wherein a microstructure comprising, in area %, 10-70% of ferrite, 10-50% of the sum of bainite and retained austenite, and a remainder of fresh martensite, wherein a ratio (Mb/Mt) is 60% or more, and methods of manufacturing these steel sheets. ([Si]+[C]×3)/([Mn]+[Mo]+[Cr])?0.18.
Type:
Grant
Filed:
July 24, 2019
Date of Patent:
March 9, 2021
Assignee:
POSCO
Inventors:
Chang Hyo Seo, Yeon Sang Ahn, Joo Hyun Ryu, Kyoo Young Lee, Won Pyo Hong
Abstract: A method for manufacturing a non-oriented electrical steel sheet according to an exemplary embodiment of the present invention includes performing hot rolling on a slab after heating the slab to manufacture a hot rolled sheet; performing hot rolled sheet annealing on the hot rolled sheet; performing cold rolling on a steel sheet on which the hot rolled sheet annealing is completed to manufacture a cold rolled sheet; and performing cold rolled sheet annealing on the cold rolled sheet in which a difference between a cold rolled sheet annealing temperature in the cold rolled sheet annealing and a hot rolled sheet annealing temperature in the hot rolled sheet annealing is 100° C. or lower.
Abstract: Provided is a plated steel sheet for hot press forming, having an excellent impact property, including: a base steel sheet comprising, by wt %, 0.15-0.4% of C, 0.05-1.0% of Si, 0.6-3.0% of Mn, 0.001-0.05% of P, 0.0001-0.02% of S, 0.01-0.1% of Al, 0.001-0.02% of N, 0.001-0.01% of B, 0.01-0.5% of Cr, 0.01-0.05% of Ti, and the balance of Fe and inevitable impurities; and an Al—Si plated layer formed on the surface of the base steel sheet. A thickness of a carbon-depleted layer in a surface layer part of the base steel sheet is 5 ?m or less. The surface layer part means a region from the surface of the base steel sheet to a depth of 200 ?m, and the carbon-depleted layer means a region which the carbon content is 50% or less of an average carbon amount (C0) of the base steel sheet.
Type:
Grant
Filed:
December 15, 2017
Date of Patent:
March 2, 2021
Assignee:
POSCO
Inventors:
Seong-Woo Kim, Jin-Keun Oh, Yeol-Rae Cho
Abstract: A core laminator of an adhesive laminate core manufacturing apparatus includes a heating unit heating an adhesive interposed between laminar members to integrate the laminar members to form a laminate core, a pinch unit rotatably provided at a lower side of the heating unit which applies a lateral pressure to the laminate core, a squeeze unit including a cylinder rotatably provided at an upper side of the heating unit and a squeezer fixed in the cylinder to align the laminar members in a straight line, a guide provided in the heating unit for guiding a movement of the laminar members, and a driving unit for selectively rotating the pinch unit and the squeeze unit.
Type:
Grant
Filed:
June 16, 2016
Date of Patent:
February 16, 2021
Assignee:
POSCO DAEWOO CORPORATION
Inventors:
Il Gwen Chung, Duk Kyoun Woo, Chan Jung Kim, Chang Don Park
Abstract: Provided is vertical semi-continuous casting equipment including a guide device disposed under the mold to support the slab drawn from the plate, the guide device being configured to guide the descending of the slab. The guide device includes first and second guide parts including a plurality of guide rolls respectively disposed on both sides of a moving path of the plate under the mold to support the slab moving by the plate and guide the movement of the slab and a braking unit connected to each of the guide rolls to apply braking force to the guide roll that rotates by the movement of the slab. In accordance with an exemplary embodiment, the slab having the length longer than that of the slab in accordance with the related art may stably descend, the shaking of the slab may be prevented, and the casting speed may be stabilized.
Type:
Grant
Filed:
October 23, 2015
Date of Patent:
February 9, 2021
Assignee:
POSCO
Inventors:
Kyung Shik Oh, Young Hoon Kang, Joo Dong Lee, Ki Hwan Joung, Un Kwan Cho
Abstract: Provided is an ultrahigh-strength steel sheet for a vehicle and, more specifically, to an ultrahigh-strength and high-ductility steel sheet having excellent yield ratio and a manufacturing method therefor. Provided is an ultrahigh-strength and high-ductility steel sheet for cold press forming and a manufacturing method therefor, the steel sheet ensuring ultrahigh strength and high ductility since an alloy component of steel and manufacturing conditions are controlled and, simultaneously, having excellent impact characteristics due to a high yield strength ratio (yield ratio). Provided is the steel sheet capable of satisfying formability and impact stability, which are required for a vehicle steel sheet for cold forming, and replacing a conventional steel sheet for hot press forming, thereby reducing manufacturing costs.
Type:
Grant
Filed:
April 20, 2017
Date of Patent:
February 2, 2021
Assignees:
POSCO, POSTECH ACADEMY-INDUSTRY FOUNDATION
Inventors:
Joo-Hyun Ryu, Nack-Joon Kim, Sung-Hak Lee, Won-Hwi Lee, Kyoo-Young Lee, Sea-Woong Lee
Abstract: A plated steel material includes a plated layer containing, by wt %: 0.5 to 14% of Al, 0.5 to 5% of Mg, and the balance being Zn and inevitable impurities. The plated steel material satisfies the following Equation: ([Mg]S?[Mg]1/2)/[Mg]1/2?0.3. [Mg]S means a content (wt %) of Mg in a surface of the plated layer, and [Mg]1/2 means a content (wt %) of Mg at a ½t position (t represents a thickness of the plated layer) from the surface of the plated layer in a thickness direction.
Type:
Grant
Filed:
December 16, 2016
Date of Patent:
February 2, 2021
Assignee:
POSCO
Inventors:
Min-Suk Oh, Jong-Sang Kim, Il-Ryoung Sohn, Tae-Chul Kim
Abstract: Provided are a hot-dip galvanized steel sheet and a hot-dip galvannealed steel sheet with excellent aging-resistance properties and bake hardenability, and a method for manufacturing the same. The hot-dip galvanized steel sheet has a molten zinc plated layer on the surface of a base steel sheet, wherein the base steel sheet comprises: 0.002-0.012 wt % of carbon (C); 1.6-2.7 wt % of manganese (Mn); 0.03 wt % or less (excluding 0 wt %) of phosphorus (P); 0.01 wt % or less (excluding 0 wt %) of sulfur (S); 0.01 wt % or less (excluding 0 wt %) of nitrogen (N); 0.02-0.06 wt % of aluminum (sol.Al); 1.0 wt % or less (excluding 0 wt %) of chromium (Cr), with the remainder being iron and inevitable impurities; the base steel sheet satisfies the relation of 1.3?Mn(wt %)/(1.15×Cr(wt %))?20.5; Mneq defined by relational expression 1 satisfies 1.9?Mneq?3.9.
Abstract: An oriented electrical steel sheet according to an exemplary embodiment of the present invention includes Si: 2.0 to 7.0%, C: 0.005% or less (excluding 0%), Al: 0.05% or less (excluding 0%), N: 0.005% or less (excluding 0%), S: 0.005% or less (excluding 0%), a content of each of Ba and Y or a sum thereof: 0.001 to 0.3%, and Fe and other unavoidable impurities as a balance by wt %.
Type:
Grant
Filed:
December 22, 2016
Date of Patent:
February 2, 2021
Assignee:
POSCO
Inventors:
Hyung Don Joo, Hyung Ki Park, Jin Wook Seo, Sang Woo Lee
Abstract: Provided is a high-strength hot-dip galvanized steel sheet having good surface quality and spot weldability. The high-strength hot-dip galvanized steel sheet includes a base steel sheet and a zinc plating layer formed on the base steel sheet. The base steel sheet includes carbon (C): 0.1% to 0.3%, silicon (Si): 0.5% to 2.5%, manganese (Mn): 2.0% to 8.0%, soluble aluminum (sol.Al): 0.001% to 0.5%, phosphorus (P): 0.04% or less (excluding 0%), sulfur (S): 0.015% or less, nitrogen (N): 0.02% or less, chromium (Cr): 0.01% to 0.7%, titanium (Ti): (48/14)*[N] % to 0.1%, and a balance of iron (Fe) and inevitable impurities. The base steel sheet has a microstructure comprising ferrite in an area fraction of 5% to 30%, austenite in an area fraction of 5% to 20%, bainite and martensite in an area fraction of 50% to 80%, and precipitates in an area fraction of 2% or less.
Type:
Grant
Filed:
December 13, 2016
Date of Patent:
January 26, 2021
Assignee:
POSCO
Inventors:
Myung-Soo Kim, Ki-Cheol Kang, Il-Jeong Park
Abstract: A lithium titanium composite oxide including aluminum-coated primary particles and a method for manufacturing the same are disclosed. A lithium titanium composite oxide including aluminum-coated primary particles according to an embodiment is manufactured by coating lithium titanium oxide primary particles with aluminum by mixing an aluminum compound with re-pulverized particles and then by spray-drying the mixture again to prepare secondary particles. A battery including the lithium titanium composite oxide including the aluminum-coated primary particles exhibits effects of suppressing electrolyte decomposition and gas generation that may be respectively caused by titanium ions and residual lithium in conventional lithium titanium composite oxides.
Type:
Application
Filed:
March 12, 2019
Publication date:
January 21, 2021
Applicant:
POSCO CHEMICAL CO., LTD
Inventors:
Su Bong CHOI, Chun Gu KANG, Jeong Han KIM, Jae An LEE
Abstract: A high strength steel sheet mainly used as an automotive exterior panel material is provided. In detail, a complex-phase steel sheet having excellent formability and a method of manufacturing the same are provided. A steel sheet may have excellent strength and ductility, and a relatively low yield ratio and an excellent surface quality may be provided.
Abstract: Disclosed are a non-quenched and tempered wire rod and a manufacturing method therefor, the non-quenched and tempered wire rod comprising in percentage by weight: 0.15 to 0.30% of C; 0.05 to 0.3% of Si; 1.0 to 2.0% of Mn; 0.5% of less of Cr (except for 0%); 0.02% or less of P; 0.02% or less of S; 0.01 to 0.05% of sol. Al; 0.005 to 0.02% of Nb; 0.05 to 0.2% of V; 0.01% or less of N; Fe as the remainder; and unavoidable impurities, wherein the non-quenched and tempered wire rod satisfies the following formulas 1 and 2, wherein, when the hardness of the wire rod measured in ½d position and in ¼d position in the diameter direction of the wire rod is Hv,1/2d(Hv) and Hv,1/4d(Hv), respectively (here, d is the diameter of the wire). (Hv,1/2d+Hv,1/4d)/2?240??[Formula 1] Hv,1/2d/Hv,1/4d?1.
Type:
Grant
Filed:
November 11, 2016
Date of Patent:
January 12, 2021
Assignee:
POSCO
Inventors:
Dong-Jun Mun, Sang-Yoon Lee, Yong-Kwan Heo, Ha-Ni Kim