公开(公告)号：US20240401173A1

公开(公告)日：2024-12-05

申请号：US18691253

申请日：2022-12-20

Applicant: POSCO CO., LTD

Inventor： Jin-Keun Oh ,  Seong-Woo Kim ,  Sea-Woong Lee ,  Sang-Heon Kim ,  Jae-Seong Park ,  Ru-Ri Lee

IPC: C22C38/04 ,  C22C21/00 ,  C22C38/02 ,  C22C38/06 ,  C22C38/28 ,  C22C38/32 ,  C23C2/12 ,  C23C2/20

Abstract: The present disclosure relates to a plated steel sheet for hot press forming, having excellent paint adhesion and corrosion resistance after hot press forming; a preparation method for the plated steel sheet; and a hot press formed member. The plated steel sheet according to an aspect of the present disclosure comprises a base steel sheet and a plating layer consisting of Al—Fe alloy formed on the base steel sheet, wherein the sum of contents of Al and Fe in the plating layer is 80% or more by weight, the average content of Fe in the plating layer is 20% or more by weight, and the product of Ra and RPC of the surface of the plating layer may be 60-150 μm/cm. Here, Ra represents arithmetic mean roughness and the unit thereof is μm, and RPc represents the number of peaks per unit length and the unit thereof is /cm.

公开(公告)号：US20240301527A1

公开(公告)日：2024-09-12

申请号：US18666200

申请日：2024-05-16

Applicant: POSCO CO., LTD

Inventor： Jin-Keun Oh ,  Yeol-Rae Cho ,  A-Ra Cho ,  Jin-Ho Cha ,  Si-Myoung Heo ,  Jeong-Won Seo ,  Seong-Woo Kim

IPC: C21D9/46 ,  B21B3/02 ,  B21D22/02 ,  C21D6/00 ,  C21D8/02 ,  C22C38/00 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/20 ,  C22C38/22 ,  C22C38/24 ,  C22C38/26 ,  C22C38/50 ,  C22C38/54

CPC classification number: C21D9/46 ,  B21B3/02 ,  B21D22/022 ,  C21D6/004 ,  C21D6/005 ,  C21D6/008 ,  C21D8/0205 ,  C21D8/0226 ,  C21D8/0236 ,  C21D8/0247 ,  C22C38/001 ,  C22C38/002 ,  C22C38/008 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/20 ,  C22C38/22 ,  C22C38/24 ,  C22C38/26 ,  C22C38/50 ,  C22C38/54 ,  C21D2211/003 ,  C21D2211/005

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 %).

公开(公告)号：US20240295003A1

公开(公告)日：2024-09-05

申请号：US18643362

申请日：2024-04-23

Applicant: POSCO CO., LTD

Inventor： Seong-Woo Kim ,  Jin-Keun Oh ,  Sang-Heon Kim ,  Sang-Bin Han

IPC: C21D9/48 ,  B32B15/01 ,  C21D6/00 ,  C21D8/04 ,  C22C38/00 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/28 ,  C22C38/32 ,  C23C2/02 ,  C23C2/12 ,  C23C2/28 ,  C23C2/40

CPC classification number: C21D9/48 ,  B32B15/012 ,  C21D6/002 ,  C21D6/005 ,  C21D6/008 ,  C21D8/0405 ,  C21D8/0421 ,  C21D8/0447 ,  C22C38/001 ,  C22C38/002 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/28 ,  C22C38/32 ,  C23C2/02 ,  C23C2/12 ,  C23C2/28 ,  C23C2/29 ,  C23C2/40

Abstract: The present invention pertains to a hot press forming member having excellent resistance to hydrogen embrittlement, and a method for manufacturing same. An aspect of the present invention provides a hot press forming member having excellent resistance to hydrogen embrittlement, the hot press forming member comprising a base steel plate and an alloy-plated layer formed on the surface of the base steel plate, wherein the alloy-plated layer contains pores such that pores having a size of 5 μm or less constitute 3-30% of the surface area of the alloy-plated layer as viewed in a cross-section taken in the thickness direction of the member.

公开(公告)号：US11788166B2

公开(公告)日：2023-10-17

申请号：US18114387

申请日：2023-02-27

Applicant: POSCO Co., Ltd

Inventor： Jin-Keun Oh ,  Yeol-Rae Cho ,  A-Ra Cho ,  Jin-Ho Cha ,  Si-Myoung Heo ,  Jeong-Won Seo ,  Seong-Woo Kim

IPC: C21D9/46 ,  B21B3/02 ,  B21D22/02 ,  C21D6/00 ,  C21D8/02 ,  C22C38/00 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/20 ,  C22C38/22 ,  C22C38/24 ,  C22C38/26 ,  C22C38/50 ,  C22C38/54

CPC classification number: C21D9/46 ,  B21B3/02 ,  B21D22/022 ,  C21D6/004 ,  C21D6/005 ,  C21D6/008 ,  C21D8/0205 ,  C21D8/0226 ,  C21D8/0236 ,  C21D8/0247 ,  C22C38/001 ,  C22C38/002 ,  C22C38/008 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/20 ,  C22C38/22 ,  C22C38/24 ,  C22C38/26 ,  C22C38/50 ,  C22C38/54 ,  C21D2211/003 ,  C21D2211/005

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 %).

公开(公告)号：US20230086620A1

公开(公告)日：2023-03-23

申请号：US17983759

申请日：2022-11-09

Applicant: POSCO

Inventor： Jin-Keun Oh ,  Seong-Woo Kim ,  Sang-Heon Kim ,  Yeol-Rae Cho

IPC: B32B15/01 ,  C22C38/00 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/28 ,  C22C38/32 ,  C23C2/12 ,  C23C2/28 ,  C23C2/40 ,  C23C24/04 ,  C23C28/02

Abstract: The present invention provides a steel sheet plated with aluminum-iron and a preparation method therefor, the steel sheet comprising: a base steel sheet; and a plated layer formed on the surface of the base steel sheet and comprising: an alloyed layer containing at least one of Fe3Al, FeAl(Si), Fe2Al5, and FeAl3; and an aluminum layer formed on the alloyed layer and having a thickness less than 10% of that of the plated layer, wherein the plated layer is 20-35 μm in thickness and contains 1-20 wt % of Mg as measured by GDS at a position 0.1 μm deep from the surface of the plated layer and 10 wt % of oxygen as measured by GDS at a position 0.1 μm deep from the surface of the plated layer.

公开(公告)号：US11578397B2

公开(公告)日：2023-02-14

申请号：US17296458

申请日：2019-11-20

Applicant: POSCO

Inventor： Seong-Woo Kim ,  Jin-Keun Oh ,  Sang-Heon Kim ,  Hyo-Sik Chun

IPC: B32B15/01 ,  C23C2/28 ,  B21D35/00 ,  C21D6/00 ,  C21D9/46 ,  C22C38/00 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/28 ,  C22C38/32 ,  C23C2/12 ,  C23C2/40

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.

公开(公告)号：US20230039057A1

公开(公告)日：2023-02-09

申请号：US17967618

申请日：2022-10-17

Applicant: POSCO

Inventor： Seong-Woo Kim ,  Jin-Keun Oh ,  Sang-Heon Kim ,  Yeol-Rae Cho

IPC: C23C2/12 ,  C22C38/06 ,  C22C38/04 ,  C22C38/00 ,  C22C21/02 ,  C21D9/48 ,  B32B15/01 ,  C22C38/02

Abstract: A method of manufacturing a steel sheet plated with an Al—Fe alloy for hot forming. The method includes: aluminum-plating and coiling a base steel sheet to obtain an aluminum-plated steel sheet, where an amount of the aluminum-plating is 30 to 200 g/m2 based on one surface of the base steel sheet, and tension in the coiling is 0.5 to 5 kg/mm2; after the aluminum-plating, performing cooling to 250° C. at a rate of 20° C./sec or less; annealing the aluminum-plated steel sheet to obtain the steel sheet plated with the Al—Fe alloy; and cooling the steel sheet plated with the Al—Fe alloy. The annealing is carried out for 30 minutes to 50 hours within a heating temperature range of 550 to 750° C. in a batch annealing furnace.

公开(公告)号：US20230002873A1

公开(公告)日：2023-01-05

申请号：US17778614

申请日：2020-12-18

Applicant: POSCO

Inventor： Seong-Woo Kim ,  Jin-Keun Oh ,  Sang-Heon Kim ,  Hyo-Sik Chun ,  Seong-Beom Bae

IPC: C22C38/22 ,  C22C38/00 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C21D8/02 ,  C23C2/12 ,  C22C21/02 ,  B21B1/24

Abstract: An embodiment of the present invention provides steel for hot forming, a hot-formed member, and methods for manufacturing same, the steel comprising, by wt %, 0.06-0.1% of C, 0.05-0.6% of Si, 0.6-2% of Mn, 0.05% or less of P, 0.02% or less of S, 0.01-0.1% of Al, 0.01-0.8% of Cr, 0.01-0.5% of Mo, 0.02% or less of N, and the remainder of Fe and inevitable impurities, wherein an alloy factor represented by relational expression 1 below is 7 or more, and the number of carbides having a circular equivalent diameter of 0.5 μm or greater is 105/mm2 or less. Alloy factor=I(Mn)×I(Si)×I(Cr)×I(Mo)  [Relational expression 1] where the I values for the components are I(Mn)=3.34×Mn+1, I(Si)=0.7×Si+1, I(Cr)=2.16×Cr+1, and I(Mo)=3×Mo+1, respectively, and the content of each component is expressed as wt %.

公开(公告)号：US20220025479A1

公开(公告)日：2022-01-27

申请号：US17311219

申请日：2019-12-19

Applicant: POSCO

Inventor： Seong-Woo Kim ,  Jin-Keun Oh ,  Sang-Heon Kim ,  Yeol-Rae Cho

IPC: C21D9/46 ,  C21D8/02 ,  C22C38/00 ,  C22C38/28 ,  C22C38/32 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C25D3/22 ,  C25D3/44 ,  B21D22/02

Abstract: The present invention provides: a plated steel sheet for hot press forming having excellent impact properties after hot press forming; a hot press formed member manufactured using the plated steel sheet for hot press forming; and manufacturing methods thereof. The plated steel sheet comprises: a base steel sheet containing, by weight, 0.15-0.4% of C, 0.1-1% of Si, 0.6-8% 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, and 0.01-0.5% of Cr, with the remainder comprising Fe and miscellaneous impurities; and a plating layer formed on the surface of the base steel sheet and composed of zinc, aluminum, or an alloy containing zinc and aluminum, wherein the ratio (C S/C B) of the content (C S) of C in a surface layer to the content (C B) of C in the base steel sheet is 0.6 or less, and the ratio ((Mn S+Cr S)/(Mn B+Cr B)) of the total content (Mn S+Cr S) of Mn and Cr in the surface layer to the total content (Mn B+Cr B) of Mn and Cr in the base steel sheet is 0.8 or more.

公开(公告)号：US11193189B2

公开(公告)日：2021-12-07

申请号：US16469942

申请日：2017-12-07

Applicant: POSCO

Inventor： Min-Seo Koo ,  Seong-Woo Kim

IPC: C22C38/38 ,  C21D6/00 ,  C21D8/02 ,  C21D9/46 ,  C21D9/52 ,  C22C38/00 ,  C22C38/02 ,  C22C38/06 ,  C22C38/22 ,  C22C38/24 ,  C22C38/26 ,  C22C38/28 ,  C22C38/32 ,  C23C2/06

Abstract: Provided is an ultra-high strength steel sheet used as a material of a vehicle and, more specifically, to an ultra-high strength steel sheet having excellent bendability and a manufacturing method therefor. There is an effect of providing a steel sheet by utilizing a continuous annealing furnace without having water quenching equipment, thereby simultaneously ensuring a tensile strength of 1200 MPa or greater compared with that of conventional super high strength martensite steel and having excellent shape and bending properties.