Patents by Inventor Jin Keun Oh

Jin Keun Oh has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 11952652
    Abstract: Provided is a method of manufacturing a zinc-plated steel sheet. The method includes: coating a metal on the steel sheet on a steel sheet; annealing the metal coated steel sheet; and zinc plating the annealed steel sheet by dipping in a molten zinc plating bath. Further provided is a method of manufacturing a hot-press part including: coating a metal on the steel sheet on a steel sheet; annealing the metal coated steel sheet; zinc plating the annealed steel sheet by dipping in a molten zinc plating bath; heating the zinc-plated steel sheet; and press forming the heated steel sheet.
    Type: Grant
    Filed: March 7, 2018
    Date of Patent: April 9, 2024
    Assignee: POSCO CO., LTD
    Inventors: Il-Ryoung Sohn, Jong-Sang Kim, Joong-Chul Park, Yeol-Rae Cho, Jin-Keun Oh, Han-Gu Cho, Bong-Hoon Chung, Jong-Seog Lee
  • Patent number: 11939651
    Abstract: Provided is an Al—Fe-alloy plated steel sheet for hot forming, having excellent TWB welding characteristics since excellent hardness uniformity of a TWB weld zone after hot forming is obtained by suitably controlling a batch annealing condition, after plating Al, such that an Al—Fe-alloy layer is formed; a hot forming member; and manufacturing methods therefor.
    Type: Grant
    Filed: May 31, 2018
    Date of Patent: March 26, 2024
    Assignee: POSCO CO., LTD
    Inventors: Seong-Woo Kim, Jin-Keun Oh, Yeol-Rae Cho, Hyeon-Jeong Shin
  • Publication number: 20240084429
    Abstract: The present invention provides an aluminum-iron-plated steel sheet, having excellent mold wear resistance, for hot press forming, and a manufacturing method thereof.
    Type: Application
    Filed: December 17, 2020
    Publication date: March 14, 2024
    Applicant: POSCO
    Inventors: Jin-Keun Oh, Seong-Woo Kim, Sang-Heon Kim, Hyo-Sik Chun
  • Patent number: 11904572
    Abstract: The present disclosure relates to an aluminum-based plated steel that is provided for vehicles by hot forming, an aluminum-based alloy plated steel manufactured using the same, and method of manufacturing thereof.
    Type: Grant
    Filed: March 14, 2023
    Date of Patent: February 20, 2024
    Assignee: POSCO CO., LTD
    Inventors: Jin-Keun Oh, Il-Ryoung Sohn, Seong-Woo Kim, Jeom-Soo Shin
  • Publication number: 20240051265
    Abstract: Provided is a steel sheet for a hot press formed member having excellent resistance to hydrogen delayed fracture, and a method for manufacturing the same. A steel sheet for a hot press formed member comprises: a base steel sheet; an aluminum alloy plating layer on a surface of the base steel sheet; and an oxide layer which is formed on a surface of the plating layer and has a thickness of 0.05 ?m or more.
    Type: Application
    Filed: September 27, 2023
    Publication date: February 15, 2024
    Applicant: POSCO CO., LTD
    Inventors: Seong-Woo KIM, Jin-Keun OH, Yeol-Rae CHO
  • Patent number: 11897014
    Abstract: The present disclosure provides a hot-press formed part comprising a plated steel sheet and an aluminum alloy plated layer formed on the plated steel sheet, wherein the aluminum alloy plated layer comprises: an alloying layer (I) formed on the plated steel sheet and containing, by weight %, 5-30% of Al; an alloying layer (II) formed on the alloying layer (I) and containing, by weight %, 30 to 60% of Al; an alloying layer (III) formed on the alloying layer (II) and containing, by weight %, 20-50% of Al and 5-20% of Si; and an alloying layer (IV) formed continuously or discontinuously on at least a part of the surface of the alloying layer (III), and containing 30-60% of Al, wherein the rate of the alloying layer (III) exposed on the outermost surface of the aluminum alloy plated layer is 10% or more.
    Type: Grant
    Filed: January 12, 2023
    Date of Patent: February 13, 2024
    Assignee: POSCO CO., LTD
    Inventors: Seong-Woo Kim, Jin-Keun Oh, Sang-Heon Kim, Hyo-Sik Chun
  • Publication number: 20240026479
    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.
    Type: Application
    Filed: October 2, 2023
    Publication date: January 25, 2024
    Applicant: POSCO CO., LTD
    Inventors: Jin-Keun OH, Seong-Woo KIM, Yeol-Rae CHO, Won-Mo BAK
  • Publication number: 20240009963
    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.
    Type: Application
    Filed: September 25, 2023
    Publication date: January 11, 2024
    Applicant: POSCO Co., Ltd.
    Inventors: Seong-Woo KIM, Jin-Keun OH, A-Ra CHO, Hyeon-Jeong SHIN
  • Publication number: 20240011138
    Abstract: An embodiment of the present invention provides a method for manufacturing a tailor welded blank using a steel sheet for hot pressing having an Al-Fe-based intermetallic alloy layer, the method comprising the steps of: preparing a plated steel sheet having a base steel sheet and an aluminum-based plated layer formed on one surface or both surfaces of the base steel sheet; heat-treating the plated steel sheet so that the aluminum-based plated layer becomes an Al-Fe-based intermetallic alloy layer; and subjecting the heat-treated plated steel sheet to butt welding, wherein, before the welding, a part or the entirety of the Al-Fe-based intermetallic alloy layer located in an area to be welded is removed.
    Type: Application
    Filed: December 17, 2021
    Publication date: January 11, 2024
    Applicant: POSCO CO., LTD
    Inventors: Sang-Ho UHM, Jin-Keun OH
  • Publication number: 20230416863
    Abstract: An aspect of the present invention relates to a cold-rolled steel plate for hot forming, which is excellent in corrosion-resistance and spot-weldability, contains, by weight %, C: 0.1-0.4%, Si: 0.5-2.0%, Mn: 0.01-4.0%, Al: 0.001-0.4%, P: 0.001-0.05%, S: 0.0001-0.02%, Cr: 0.5% to less than 3.0%, N: 0.001-0.02%, and a balance of Fe and inevitable impurities, satisfying formula (1) below, and includes an Si amorphous oxidation layer continuously or discontinuously formed at a thickness of 1 nm-100 nm on the surface thereof. Formula (1): 1.4?0.4*Cr+Si?3.2 (wherein element symbols denote measurements of respective element contents by weight %).
    Type: Application
    Filed: September 5, 2023
    Publication date: December 28, 2023
    Applicant: POSCO Co., Ltd
    Inventors: Jin-Keun OH, Yeol-Rae CHO, A-Ra CHO, Jin-Ho CHA, Si-Myoung HEO, Jeong-Won SEO, Seong-Woo KIM
  • Publication number: 20230383373
    Abstract: Provided are plated steel sheets for hot press forming, hot press formed parts, and manufacturing methods thereof, the plated steel sheets comprising: a base steel sheet comprising, in weight %, C: 0.07 to 0.5%, Si: 0.05 to 1%, Mn: 0.5 to 5%, P: 0.001 to 0.015%, S: 0.0001 to 0.02%, Al: 0.01 to 0.1%, Cr: 0.01 to 1%, N: 0.001 to 0.02%, Ti: 0.1% or less, B: 0.01% or less, Sn: 0.01 to 0.1%, and a balance of Fe and inevitable impurities; an aluminum or aluminum alloy plating layer disposed on at least one surface of the base steel sheet; and an Sn-enriched layer provided between the base steel sheet and the plating layer, wherein the Sn-enriched layer satisfies a specific relationship.
    Type: Application
    Filed: December 3, 2021
    Publication date: November 30, 2023
    Applicant: POSCO Co., Ltd
    Inventors: Jin-Keun Oh, Seong-Woo Kim, Sang-Heon Kim, Hyo-Sik Chun
  • Patent number: 11827947
    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.
    Type: Grant
    Filed: July 7, 2017
    Date of Patent: November 28, 2023
    Assignee: POSCO CO., LTD
    Inventors: Jin-Keun Oh, Seong-Woo Kim, Yeol-Rae Cho, Won-Mo Bak
  • Patent number: 11820103
    Abstract: The present invention relates to a steel sheet for a hot press formed member having excellent coating adhesion, and a method for manufacturing the same. A steel sheet for hot press forming according to one aspect of the present invention is an aluminum alloy plated steel sheet, wherein an average Fe content in a plating layer may be 40 wt % or more, and a concentration gradient of a section having a Fe content of 45 wt % to 80 wt % in the plating layer may 7 wt %/?m or less of 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.
    Type: Grant
    Filed: November 2, 2021
    Date of Patent: November 21, 2023
    Assignee: POSCO CO., LTD
    Inventors: Seong-Woo Kim, Jin-Keun Oh, A-Ra Cho, Hyeon-Jeong Shin
  • Patent number: 11801664
    Abstract: Provided is a steel sheet for a hot press formed member having excellent resistance to hydrogen delayed fracture, and a method for manufacturing the same. A steel sheet for a hot press formed member comprises: a base steel sheet; an aluminum alloy plating layer on a surface of the base steel sheet; and an oxide layer which is formed on a surface of the plating layer and has a thickness of 0.05 ?m or more.
    Type: Grant
    Filed: April 25, 2022
    Date of Patent: October 31, 2023
    Assignee: POSCO CO., LTD.
    Inventors: Seong-Woo Kim, Jin-Keun Oh, Yeol-Rae Cho
  • Patent number: 11788166
    Abstract: An aspect of the present invention relates to a cold-rolled steel plate for hot forming, which is excellent in corrosion-resistance and spot-weldability, contains, by weight %, C: 0.1-0.4%, Si: 0.5-2.0%, Mn: 0.01-4.0%, Al: 0.001-0.4%, P: 0.001-0.05%, S: 0.0001-0.02%, Cr: 0.5% to less than 3.0%, N: 0.001-0.02%, and a balance of Fe and inevitable impurities, satisfying formula (1) below, and includes an Si amorphous oxidation layer continuously or discontinuously formed at a thickness of 1 nm-100 nm on the surface thereof. Formula (1): 1.4?0.4*Cr+Si?3.2 (wherein element symbols denote measurements of respective element contents by weight %).
    Type: Grant
    Filed: February 27, 2023
    Date of Patent: October 17, 2023
    Assignee: POSCO CO., LTD
    Inventors: Jin-Keun Oh, Yeol-Rae Cho, A-Ra Cho, Jin-Ho Cha, Si-Myoung Heo, Jeong-Won Seo, Seong-Woo Kim
  • Publication number: 20230287535
    Abstract: One aspect of the present invention relates to a plated steel sheet for hot press forming, having an excellent impact property.
    Type: Application
    Filed: May 19, 2023
    Publication date: September 14, 2023
    Applicant: POSCO CO., LTD
    Inventors: Seong-Woo KIM, Jin-Keun OH, Yeol-Rae CHO
  • Publication number: 20230286030
    Abstract: Provided are a plated steel sheet for hot press forming including: a base steel sheet containing, by wt%, 0.14 to 0.5% of C, 0.001 to 1% of Si, 0.3 to 4% of Mn, 0.001 to 0.015% of P, 0.0001 to 0.02% of S, 0.001 to 0.1% of Al, 0.001 to 1% of Cr, 0.001 to 0.02% of N, 0.1% or less of Ti, 0.01% or less of B, 0.005 to 0.1% of Sb, and a balance of Fe and unavoidable impurities; an aluminum or aluminum alloy plating layer provided on at least one surface of the base steel sheet; and a Sb-rich layer provided between the base steel sheet and the plating layer, wherein the plated steel sheet for hot press forming satisfies the following Relational Expressions 1-1 and 1-2, a hot press formed member manufactured using the same, and methods for manufacturing the plated steel sheet for hot press forming and the hot press formed member. S b max S b c o a t ? 1.2 ­­­[Relational Expression 1-1] S b max ? S b c o a t 2 × ? t ? 0.
    Type: Application
    Filed: October 19, 2021
    Publication date: September 14, 2023
    Applicant: POSCO Co., Ltd
    Inventors: Sang-Heon Kim, Jin-Keun Oh, Seong-Woo Kim, Sang-Bin Han
  • Patent number: 11732323
    Abstract: One aspect of the present invention relates to a plated steel sheet for hot press forming, having an excellent impact property.
    Type: Grant
    Filed: February 8, 2022
    Date of Patent: August 22, 2023
    Assignee: POSCO
    Inventors: Seong-Woo Kim, Jin-Keun Oh, Yeol-Rae Cho
  • Publication number: 20230235423
    Abstract: An aspect of the present invention relates to a cold-rolled steel plate for hot forming, which is excellent in corrosion-resistance and spot-weldability, contains, by weight %, C: 0.1-0.4%, Si: 0.5-2.0%, Mn: 0.01-4.0%, Al: 0.001-0.4%, P: 0.001-0.05%, S: 0.0001-0.02%, Cr: 0.5% to less than 3.0%, N: 0.001-0.02%, and a balance of Fe and inevitable impurities, satisfying formula (1) below, and includes an Si amorphous oxidation layer continuously or discontinuously formed at a thickness of 1 nm-100 nm on the surface thereof. Formula (1): 1.4?0.4*Cr+Si?3.2 (wherein element symbols denote measurements of respective element contents by weight %).
    Type: Application
    Filed: February 27, 2023
    Publication date: July 27, 2023
    Applicant: POSCO Co., Ltd
    Inventors: Jin-Keun OH, Yeol-Rae CHO, A-Ra CHO, Jin-Ho CHA, Si-Myoung HEO, Jeong-Won SEO, Seong-Woo KIM
  • Publication number: 20230227956
    Abstract: The present disclosure provides a hot-press formed part comprising a plated steel sheet and an aluminum alloy plated layer formed on the plated steel sheet, wherein the aluminum alloy plated layer comprises: an alloying layer (I) formed on the plated steel sheet and containing, by weight %, 5-30% of Al; an alloying layer (II) formed on the alloying layer (I) and containing, by weight %, 30 to 60% of Al; an alloying layer (III) formed on the alloying layer (II) and containing, by weight %, 20-50% of Al and 5-20% of Si; and an alloying layer (IV) formed continuously or discontinuously on at least a part of the surface of the alloying layer (III), and containing 30-60% of Al, wherein the rate of the alloying layer (III) exposed on the outermost surface of the aluminum alloy plated layer is 10% or more.
    Type: Application
    Filed: March 20, 2023
    Publication date: July 20, 2023
    Applicant: POSCO CO, LTD
    Inventors: Seong-Woo KIM, Jin-Keun OH, Sang-Heon KIM, Hyo-Sik CHUN