公开(公告)号：US11008634B2

公开(公告)日：2021-05-18

申请号：US16174780

申请日：2018-10-30

Applicant: KOREA INSTITUTE OF INDUSTRIAL TECHNOLOGY

Inventor： Min-Ha Lee ,  Joong-Hwan Jun ,  Chae-Ho Lim ,  Song-Yi Kim ,  Jin-Gu Han

IPC: C21D9/18 ,  C22C38/00 ,  C21D1/18 ,  C21D1/32 ,  C21D6/00 ,  C21D8/00 ,  C22C38/02 ,  C22C38/04 ,  C22C38/22 ,  C22C38/24 ,  C22C38/28 ,  B23D35/00

Abstract: A tool steel having strength and high impact toughness incudes 0.7 to 0.9 wt % of C, 0.4 to 0.6 wt % of Si, 0.4 to 0.6 wt % of Mn, 7.0 to 9.0 wt % of Cr, 1.5 to 2.5 wt % of Mo, up to 1.0 wt % or less (excluding 0 wt %) of V, 0.01 to 0.06 wt % of Ce, and a remainder of Fe and inevitable impurities, wherein the tool steel has a hardness of 59 to 65 HRC and an impact toughness of 30 to 42 J/cm2. The tool steel has super-high-strength combined with high impact toughness due to inclusion of Ce, thus reducing primary carbide content in an as-cast state and after solution treatment and tempering.