公开(公告)号：US20240401166A1

公开(公告)日：2024-12-05

申请号：US18799527

申请日：2024-08-09

Applicant: POSCO CO., LTD ,  POSTECH ACADEMY-INDUSTRY FOUNDATION

Inventor： Sea-Woong LEE ,  Bruno C. DE COOMAN ,  Kyoo-Young LEE ,  Eun-Jung SEO ,  Seon-Jong LEE ,  Joo-Hyun RYU ,  Won-Hwi LEE

IPC: C21D9/46 ,  C21D6/00 ,  C21D8/02 ,  C22C38/00 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/12 ,  C22C38/38 ,  C23C2/02 ,  C23C2/06 ,  C23C2/28 ,  C23C2/40

Abstract: One aspect of the present invention relates to an ultrahigh-strength steel sheet having an excellent yield ratio, comprising, by wt %, 0.3-0.5% of C, 2.0% (excluding 0%) of Si, 3.0-6.5% of Mn, 0.02% or less of P, 0.01% or less of S, 0.01-3.0% of Al, 0.02% or less (excluding 0%) of N, and the balance of Fe and other inevitable impurities, and a microstructure comprises 5-30% of remaining austenite by area fraction and comprises 5% or less of secondary martensite.

公开(公告)号：US20190256940A1

公开(公告)日：2019-08-22

申请号：US16347704

申请日：2017-11-07

Applicant: POSCO ,  POSTECH ACADEMY-INDUSTRY FOUNDATION

Inventor： Sea-Woong LEE ,  Bruno C. DE COOMAN ,  Kyoo-Young LEE ,  Eun-Jung SEO ,  Seon-Jong LEE ,  Joo-Hyun RYU ,  Won-Hwi LEE

IPC: C21D9/46 ,  C21D8/02 ,  C21D6/00 ,  C23C2/02 ,  C23C2/06 ,  C23C2/40 ,  C22C38/38 ,  C22C38/12 ,  C22C38/06 ,  C22C38/04 ,  C22C38/02 ,  C22C38/00

Abstract: One aspect of the present invention relates to an ultrahigh-strength steel sheet having an excellent yield ratio, comprising, by wt %, 0.3-0.5% of C, 2.0% (excluding 0%) of Si, 3.0-6.5% of Mn, 0.02% or less of P, 0.01% or less of S, 0.01-3.0% of Al, 0.02% or less (excluding 0%) of N, and the balance of Fe and other inevitable impurities, and a microstructure comprises 5-30% of remaining austenite by area fraction and comprises 5% or less of secondary martensite.