Title:
LOW-CARBON LOW-ALLOY TRIP STEEL OR HOT-DIP GALVANIZED TRIP STEEL HAVING TENSILE STRENGTH GREATER THAN OR EQUAL TO 980 MPA, AND MANUFACTURING METHOD THEREFOR
Document Type and Number:
WIPO Patent Application WO/2022/206912
Kind Code:
A1
Abstract:
A low-carbon low-alloy TRIP steel or hot-dip galvanized TRIP steel having a tensile strength greater than or equal to 980 MPa, comprising the following chemical components in percentage by mass: C: 0.17-0.25%, Si: 1.1-2.0%, Mn: 1.6-2.4%, P≤0.015%, S≤0.002%, and Al: 0.02-0.05%, and further comprising one or two of Cr, Mo, Ti, Nb, and V, wherein Cr+Mo+Ti+Nb+V≤0.5%, with the balance being Fe and other inevitable impurities. A manufacturing method therefor comprises: smelting, casting, hot rolling, cold rolling, and rapid heat treatment or rapid heat treatment hot dipping; the duration of the whole rapid heat treatment process is 281-350 s, and the duration of the whole rapid heat treatment hot dipping process is 118-328 s. In the present invention, rapid heating, short-term thermal insulation, and rapid cooling processes in the rapid heat treatment process are controlled, recovery, recrystallization, and austenite phase transformation processes of a deformed structure are changed, a nucleation rate is increased, a grain growth time is shortened, and grains are fined, thereby finally obtaining a TRIP steel whose microstructure is a bainite, ferrite and austenite multiphase structure, and has an average grain size of 1-3 μm. Good plasticity and toughness are obtained while the strength of a material is enhanced.
Inventors:
LI JUN (CN)
WANG JIAN (CN)
ZHANG LIXIANG (CN)
ZHANG BAOPING (CN)
ZHANG LIYANG (CN)
CHEN PEILIN (CN)
CHEN YUNPENG (CN)
MENG QINGGE (CN)
DU XIAOFENG (CN)
MA XINJIAN (CN)
WANG JIAN (CN)
ZHANG LIXIANG (CN)
ZHANG BAOPING (CN)
ZHANG LIYANG (CN)
CHEN PEILIN (CN)
CHEN YUNPENG (CN)
MENG QINGGE (CN)
DU XIAOFENG (CN)
MA XINJIAN (CN)
Application Number:
PCT/CN2022/084524
Publication Date:
October 06, 2022
Filing Date:
March 31, 2022
Export Citation:
Assignee:
BAOSHAN IRON & STEEL (CN)
International Classes:
C23C2/06; C21D9/52; C22C38/02; C22C38/04; C23C2/40
Domestic Patent References:
| WO2016001710A1 | 2016-01-07 |
Foreign References:
| CN109943769A | 2019-06-28 | |||
| CN109943770A | 2019-06-28 | |||
| CN111945076A | 2020-11-17 | |||
| CN110747391A | 2020-02-04 | |||
| CN106636899A | 2017-05-10 | |||
| CN102492823A | 2012-06-13 | |||
| EP2000554A1 | 2008-12-10 | |||
| US20170130290A1 | 2017-05-11 |
Attorney, Agent or Firm:
SHANGHAI PATENT & TRADEMARK LAW OFFICE, LLC (CN)
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