公开(公告)号：US11220731B2

公开(公告)日：2022-01-11

申请号：US16065321

申请日：2016-12-23

Applicant: POSCO

Inventor： Hwan-Goo Seong ,  Seong-Beom Bae

IPC: C22C38/14 ,  C21D8/02 ,  C22C38/00 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/12 ,  C23C2/02 ,  C23C2/06 ,  C23C2/12 ,  C23C2/40

Abstract: Provided is a hot-rolled coated steel sheet having a yield point elongation of less than 4% and a manufacturing method for the same. The hot-rolled steel sheet comprises, by weight, 0.03 to 0.06% of carbon (C), 0.5 to 1.5% of manganese (Mn), 0.01 to 0.25% of silicon (Si), 0.01 to 0.05% of aluminum (Al), 0.001 to 0.02% of phosphorus (P), 0.006% or less of sulfur (S), 0.0001 to 0.02% of titanium (Ti), 0.0001 to 0.03% of niobium (Nb), 0.001 to 0.005% of nitrogen (N), and a balance of iron (Fe) and inevitable impurities, wherein the Ti, Al and N satisfy the following relationship 1, and the Nb, C and N satisfy the following relationship 2: 0.03≤(wt % Ti)×(wt % Al)×(wt % N)×106≤0.20 (1), and 22≤(mol % Nb)/{(mol % C)×(mol % N)}≤1826 (2).

公开(公告)号：US20210062313A1

公开(公告)日：2021-03-04

申请号：US16957948

申请日：2018-12-14

Applicant: POSCO

Inventor： Hwan-Goo Seong ,  Yeol-Rae Cho ,  Seong-Beom Bae

IPC: C22C38/54 ,  C22C38/42 ,  C22C38/50 ,  C22C38/44 ,  C22C38/06 ,  C22C38/04 ,  C22C38/02 ,  C22C38/00 ,  C21D9/46 ,  C21D9/08 ,  C21D8/02 ,  C21D8/10 ,  C21D6/00

Abstract: A preferable aspect of the present invention provides: a hot-rolled steel sheet containing, by weight, 0.35-0.55% of C, 0.7-1.5% of Mn, 0.3% or less of Si, 0.03% or less of P, 0.004% or less of S, 0.04% or less of Al, 0.3% or less (excluding 0%) of Cr, 0.3% or less of Mo, one or two of 0.1-1.0% of Ni and 0.1-1.0% of Cu, 0.4% or more of Cu+Ni, 0.006% or less of N, and the balance Fe and other impurities, the alloy elements satisfying relational formulas 1 to 3 below, wherein a microstructure of the hot-rolled steel sheet comprises, by volume, 10% or more of ferrite and 90% or less of pearlite; a steel pipe and a member each using the same; and manufacturing methods therefore. [Relational formula 1] (Mn/Si)≥3 (weight ratio) [Relational formula 2] (Ni+Cu)/(C+Mn)≥0.2 (weight ratio) [Relational formula 3] (Ni/Si)≥(weight ratio).

公开(公告)号：US12258657B2

公开(公告)日：2025-03-25

申请号：US17752306

申请日：2022-05-24

Applicant: POSCO

Inventor： Hwan-Goo Seong ,  Yeol-Rae Cho ,  Seong-Beom Bae

IPC: C22C38/02 ,  C21D6/00 ,  C21D8/02 ,  C21D8/10 ,  C21D9/08 ,  C21D9/46 ,  C22C38/00 ,  C22C38/04 ,  C22C38/06 ,  C22C38/42 ,  C22C38/44 ,  C22C38/50 ,  C22C38/54

Abstract: A preferable aspect of the present invention provides: a hot-rolled steel sheet with excellent impact resistance containing, by weight, 0.35-0.55% of C, 0.7-1.5% of Mn, 0.3% or less (excluding 0%) of Si, 0.03% or less (including 0%) of P, 0.004% or less (including 0%) of S, 0.04% or less (excluding 0%) of Al, 0.3% or less (excluding 0%) of Cr, 0.3% or less (excluding 0%) of Mo, one or two of 0.1-1.0% of Ni and 0.1-1.0% of Cu, 0.4% or more of Cu+Ni, 0.006% or less (excluding 0%) of N, and the balance Fe and other impurities, the alloy elements satisfying relational formulas 1 to 3 below, wherein a microstructure of the hot-rolled steel sheet comprises, by volume, 10% or more of ferrite and 90% or less of pearlite; a steel pipe and a member each using the same; and manufacturing methods therefore. (Mn/Si)≥3 (weight ratio)  [Relational formula 1] (Ni+Cu)/(C+Mn)≥0.2 (weight ratio)  [Relational formula 2] (Ni/Si)≥(weight ratio).  [Relational formula 3]

公开(公告)号：US20240209467A1

公开(公告)日：2024-06-27

申请号：US18596117

申请日：2024-03-05

Applicant: POSCO CO, LTD

Inventor： Hwan-Goo Seong ,  Yeol-Rae Cho ,  Seong-Beom Bae

IPC: C21D8/02 ,  C21D9/08 ,  C21D9/46 ,  C22C38/00 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/10 ,  C22C38/12 ,  C22C38/28 ,  C22C38/32 ,  C23G1/00

CPC classification number: C21D8/0226 ,  C21D9/085 ,  C21D9/46 ,  C22C38/001 ,  C22C38/002 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/105 ,  C22C38/12 ,  C22C38/28 ,  C22C38/32 ,  C23G1/00 ,  C21D2211/001 ,  C21D2211/005 ,  C21D2211/008 ,  C21D2211/009

Abstract: A preferable aspect of the present invention provides: an ultra-high-strength hot-rolled steel sheet containing, by weight, one or two of 0.40-0.60% of C, 0.7-1.5% of Mn, 0.3% or less (excluding 0%) of Si, 0.03% or less (including 0%) of P, 0.004% or less (including 0%) of S, 0.04% or less (excluding 0%) of Al, 0.3% or less (excluding 0%) of Cr, 0.3% or less (excluding 0%) of Mo, 0.9-1.5% of Ni, and 0.9-1.5% of Cu, 1.1% or more of Cu+Ni, 0.04% or less (excluding 0%) of Ti, 0.005% or less (excluding 0%) of B, 0.006% or less (excluding 0%) of N, and the balance Fe and other impurities, the alloy elements satisfying relational formulas 1 and 2 below, wherein a microstructure of the hot-rolled steel sheet comprises, by volume, 7% or more of ferrite and 93% or less of perlite; a steel pipe and a member each using the same; and manufacturing methods therefor. [Relational formula 1] (Mn/Si) #3 (weight ratio) [Relational formula 2] (Ni/Si) #1 (weight ratio)

公开(公告)号：US11939639B2

公开(公告)日：2024-03-26

申请号：US16957675

申请日：2018-12-13

Applicant: POSCO

Inventor： Hwan-Goo Seong ,  Yeol-Rae Cho ,  Seong-Beom Bae

IPC: C21D8/02 ,  C21D9/08 ,  C21D9/46 ,  C22C38/00 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/10 ,  C22C38/12 ,  C22C38/28 ,  C22C38/32 ,  C23G1/00

CPC classification number: C21D8/0226 ,  C21D9/085 ,  C21D9/46 ,  C22C38/001 ,  C22C38/002 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/105 ,  C22C38/12 ,  C22C38/28 ,  C22C38/32 ,  C23G1/00 ,  C21D2211/001 ,  C21D2211/005 ,  C21D2211/008 ,  C21D2211/009

Abstract: A preferable aspect of the present invention provides: an ultra-high-strength hot-rolled steel sheet containing, by weight, one or two of 0.40-0.60% of C, 0.7-1.5% of Mn, 0.3% or less (excluding 0%) of Si, 0.03% or less (including 0%) of P, 0.004% or less (including 0%) of S, 0.04% or less (excluding 0%) of Al, 0.3% or less (excluding 0%) of Cr, 0.3% or less (excluding 0%) of Mo, 0.9-1.5% of Ni, and 0.9-1.5% of Cu, 1.1% or more of Cu+Ni, 0.04% or less (excluding 0%) of Ti, 0.005% or less (excluding 0%) of B, 0.006% or less (excluding 0%) of N, and the balance Fe and other impurities, the alloy elements satisfying relational formulas 1 and 2 below, wherein a microstructure of the hot-rolled steel sheet comprises, by volume, 7% or more of ferrite and 93% or less of perlite; a steel pipe and a member each using the same; and manufacturing methods therefor. [Relational formula 1] (Mn/Si) #3 (weight ratio) [Relational formula 2] (Ni/Si) #1 (weight ratio)

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：US20220341012A1

公开(公告)日：2022-10-27

申请号：US17752306

申请日：2022-05-24

Applicant: POSCO

Inventor： Hwan-Goo Seong ,  Yeol-Rae Cho ,  Seong-Beom Bae

IPC: C22C38/54 ,  C21D6/00 ,  C21D8/02 ,  C21D8/10 ,  C21D9/08 ,  C21D9/46 ,  C22C38/00 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/42 ,  C22C38/44 ,  C22C38/50

Abstract: A preferable aspect of the present invention provides: a hot-rolled steel sheet with excellent impact resistance containing, by weight, 0.35-0.55% of C, 0.7-1.5% of Mn, 0.3% or less (excluding 0%) of Si, 0.03% or less (including 0%) of P, 0.004% or less (including 0%) of S, 0.04% or less (excluding 0%) of Al, 0.3% or less (excluding 0%) of Cr, 0.3% or less (excluding 0%) of Mo, one or two of 0.1-1.0% of Ni and 0.1-1.0% of Cu, 0.4% or more of Cu+Ni, 0.006% or less (excluding 0%) of N, and the balance Fe and other impurities, the alloy elements satisfying relational formulas 1 to 3 below, wherein a microstructure of the hot-rolled steel sheet comprises, by volume, 10% or more of ferrite and 90% or less of pearlite; a steel pipe and a member each using the same; and manufacturing methods therefore. (Mn/Si)≥3 (weight ratio)  [Relational formula 1] (Ni+Cu)/(C+Mn)≥0.2 (weight ratio)  [Relational formula 2] (Ni/Si)≥(weight ratio)  [Relational formula 3].