Search International and National Patent Collections

1. (WO2018199145) HIGH-Mn STEEL AND PRODUCTION METHOD THEREFOR

Pub. No.:    WO/2018/199145    International Application No.:    PCT/JP2018/016764
Publication Date: Fri Nov 02 00:59:59 CET 2018 International Filing Date: Thu Apr 26 01:59:59 CEST 2018
IPC: C22C 38/00
C21D 8/02
C22C 38/38
C22C 38/58
Applicants: JFE STEEL CORPORATION
JFEスチール株式会社
Inventors: ARAO Ryo
荒尾 亮
IZUMI Daichi
泉 大地
UEDA Keiji
植田 圭治
HASE Kazukuni
長谷 和邦
Title: HIGH-Mn STEEL AND PRODUCTION METHOD THEREFOR
Abstract:
The present invention proposes a method for imparting better ductility to high-Mn steel that has superior cryogenic toughness in both a welding heat-affected part and a matrix after being welded. This high-Mn steel has a component composition comprising, in mass%, 0.30-0.90% of C, 0.05-1.0% of Si, 15-30% of Mn, not more than 0.030% of P, not more than 0.0070% of S, 0.01-0.07% of Al, 0.5-7.0% of Cr, 0.0050-0.0500% of N, not more than 0.0050% of O, the respective contained amounts of Ti and Nb being at suppressed levels of less than 0.005%, with the remaining portion being Fe and unavoidable impurities, wherein the high-Mn steel has a microstructure including austenite as a matrix phase, the area fraction of non-metal inclusion in the microstructure is less than 5.0%, and the high-Mn steel has a yield strength of at least 400 MPa and an absorption energy (vE-196) of at least 100 J.