公开(公告)号：US10822671B2

公开(公告)日：2020-11-03

申请号：US15535618

申请日：2015-12-21

申请人： POSCO

发明人： Hak-Cheol Lee ,  Sung-Ho Jang

IPC分类号： C22C38/08 ,  C22C38/12 ,  C22C38/14 ,  C22C38/16 ,  C21D9/46 ,  C22C38/04 ,  C21D6/00 ,  C21D8/02 ,  C22C38/00 ,  C22C38/02

摘要： Provided are high-strength steel having superior brittle crack arrestability and a production method therefor. The structural ultra-thick steel comprises 0.05-0.1 wt % of C, 0.9-1.5 wt % of Mn, 0.8-1.5 wt % of Ni, 0.005-0.1 wt % of Nb, 0.005-0.1 wt % of Ti, 0.1-0.6 wt % of Cu, 0.1-0.4 wt % of Si, at most 100 ppm of P, and at most 40 ppm of S with the remainder being Fe and other inevitable impurities, has microstructures including one structure selected from the group consisting of a single-phase structure of ferrite, a single-phase structure of bainite, a complex-phase structure of ferrite and bainite, a complex-phase structure of ferrite and pearlite, and a complex-phase structure of ferrite, bainite, and pearlite, and has a thickness of at least 50 mm. The high-strength steel has high yield strength and superior brittle crack arrestability.

公开(公告)号：US10689735B2

公开(公告)日：2020-06-23

申请号：US14654649

申请日：2012-12-28

申请人： POSCO

发明人： Sung-Ho Jang ,  Woo-Gyeom Kim ,  Ki-Hyun Bang

IPC分类号： C22C38/16 ,  C21D6/00 ,  C21D8/02 ,  C21D9/46 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/12 ,  C22C38/14 ,  C22C38/08 ,  C22C38/00 ,  C22C38/20

摘要： A high strength steel sheet comprises 0.02 to 0.12 wt % of carbon (C), 0.5 to 2.0 wt % of manganese (Mn), 0.05 to 0.5 wt % of silicon (Si), 0.05 to 1.0 wt % of nickel (Ni), 0.005 to 0.1 wt % of titanium (Ti), 0.005 to 0.5 wt % of aluminum (Al), 0.015 wt % or less of phosphorus (P), 0.015 wt % or less of sulfur (S), and the balance of Fe and other inevitable impurities. The microstructure thereof includes 70% to 90% of ultrafine ferrite and 10% to 30% of MA (martensite/austenite) structure by area fraction, and the yield ratio (YS/TS) thereof is 0.8 or less.

公开(公告)号：US20190390292A1

公开(公告)日：2019-12-26

申请号：US16469483

申请日：2017-12-20

申请人： POSCO

发明人： Hak-Cheol Lee ,  Sung-Ho Jang

IPC分类号： C21D9/46 ,  C21D8/02 ,  C21D6/00 ,  C22C38/14 ,  C22C38/12 ,  C22C38/08 ,  C22C38/06 ,  C22C38/02 ,  C22C38/04 ,  C22C38/00

摘要： Disclosed are a high-strength ultra-thick steel material and a method for manufacturing same. The high-strength ultra-thick steel material comprises in weight % 0.04-0.1% of C, 0.05-0.5% of Si, 0.01-0.05% of Al, 1.6-2.2% of Mn, 0.5-1.2% of Ni, 0.005-0.050% of Nb, 0.005-0.03% of Ti and 0.2-0.6% of Cu, 100 ppm or less of P and 40 ppm or less of S with a balance of Fe, and inevitable impurities, and comprises, in a subsurface area up to t/10 (t hereafter being referred to as the thickness of the steel material), bainite of 90 area % or greater (including 100 area %) as microstructures. And the particle size of crysta1lites having a high inclination angle boundary of 15° or higher measured by EBSD is 10 μm or less (not including 0 μm).

公开(公告)号：US11634784B2

公开(公告)日：2023-04-25

申请号：US16469480

申请日：2017-12-20

申请人： POSCO

发明人： Hak-Cheol Lee ,  Sung-Ho Jang

IPC分类号： C22C38/04 ,  C21D9/46 ,  C21D6/00 ,  C21D8/02 ,  C22C38/00 ,  C22C38/08 ,  C22C38/12 ,  C22C38/14 ,  C22C38/16

摘要： Disclosed are a high-strength ultra-thick steel material and a method for manufacturing same. The high-strength ultra-thick steel material comprises in weight % 0.04-0.1% of C, 1.2-2.0% of Mn, 0.2-0.9% of Ni, 0.005-0.04% of Nb, 0.005-0.03% of Ti and 0.1-0.4% of Cu, 100 ppm or less of P and 40 ppm or less of S with a balance of Fe, and inevitable impurities, and comprises, in a subsurface area up to t/10 (t hereafter being referred to as the thickness of the steel material), polygonal ferrite of 50 area % or greater (including 100 area %) and bainite of 50 area % or less (including 0 area %) as microstructures.

公开(公告)号：US11649518B2

公开(公告)日：2023-05-16

申请号：US16469483

申请日：2017-12-20

申请人： POSCO

发明人： Hak-Cheol Lee ,  Sung-Ho Jang

IPC分类号： C21D9/46 ,  C21D8/02 ,  C21D6/00 ,  C22C38/14 ,  C22C38/12 ,  C22C38/08 ,  C22C38/06 ,  C22C38/02 ,  C22C38/04 ,  C22C38/00

CPC分类号： C21D9/46 ,  C21D6/005 ,  C21D6/008 ,  C21D8/0205 ,  C21D8/0226 ,  C22C38/002 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/08 ,  C22C38/12 ,  C22C38/14 ,  C21D2211/001 ,  C21D2211/002 ,  C21D2211/005 ,  C21D2211/008

摘要： Disclosed are a high-strength ultra-thick steel material and a method for manufacturing same. The high-strength ultra-thick steel material comprises in weight % 0.04-0.1% of C, 0.05-0.5% of Si, 0.01-0.05% of Al, 1.6-2.2% of Mn, 0.5-1.2% of Ni, 0.005-0.050% of Nb, 0.005-0.03% of Ti and 0.2-0.6% of Cu, 100 ppm or less of P and 40 ppm or less of S with a balance of Fe, and inevitable impurities, and comprises, in a subsurface area up to t/10 (t hereafter being referred to as the thickness of the steel material), bainite of 90 area % or greater (including 100 area %) as microstructures. And the particle size of crystallites having a high inclination angle boundary of 15° or higher measured by EBSD is 10 μm or less (not including 0 μm).

公开(公告)号：US10883159B2

公开(公告)日：2021-01-05

申请号：US15535607

申请日：2015-12-21

申请人： POSCO

发明人： Hak-Cheol Lee ,  Sung-Ho Jang

IPC分类号： C22C38/02 ,  C22C38/04 ,  C22C38/08 ,  C22C38/12 ,  C22C38/14 ,  C22C38/16 ,  C21D8/02 ,  C21D9/46

摘要： Provided are high-strength steel having superior brittle crack arrestability and a production method therefor. The high-strength steel comprises 0.05-0.1 wt % of C, 1.5-2.2 wt % of Mn, 0.3-1.2 wt % of Ni, 0.005-0.1 wt % of Nb, 0.005-0.1 wt % of Ti, 0.1-0.5 wt % of Cu, 0.1-0.3 wt % of Si, at most 100 ppm of P, and at most 40 ppm of S with the remainder being Fe and other inevitable impurities, has microstructures including one structure selected from the group consisting of a single-phase structure of ferrite, a single phase structure of bainite, a complex-phase structure of ferrite and bainite, a complex-phase structure of ferrite and pearlite, and a complex-phase structure of ferrite, bainite, and pearlite, and has a thickness of at least 50 mm. The high-strength steel has high yield strength and superior brittle crack arrestability.