发明授权
- 专利标题： High-strength steel sheet, hot-dipped steel sheet, and alloy hot-dipped steel sheet that have excellent fatigue, elongation, and collision characteristics, and manufacturing method for said steel sheets
- 专利标题（中）： 具有优异的疲劳，伸长率和碰撞特性的高强度钢板，热浸镀锌钢板和合金热浸镀锌钢板以及所述钢板的制造方法
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申请号： US13138898申请日： 2010-05-26
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公开(公告)号： US08888933B2公开(公告)日： 2014-11-18
- 发明人: Kunio Hayashi , Toshimasa Tomokiyo , Nobuhiro Fujita , Naoki Matsutani , Koichi Goto
- 申请人： Kunio Hayashi , Toshimasa Tomokiyo , Nobuhiro Fujita , Naoki Matsutani , Koichi Goto
- 申请人地址： JP Tokyo
- 专利权人： Nippon Steel & Sumitomo Metal Corporation
- 当前专利权人： Nippon Steel & Sumitomo Metal Corporation
- 当前专利权人地址： JP Tokyo
- 代理机构： Kenyon & Kenyon LLP
- 优先权： JP2009-127340 20090527
- 国际申请： PCT/JP2010/003541 WO 20100526
- 国际公布： WO2010/137317 WO 20101202
- 主分类号： C22C38/02
- IPC分类号： C22C38/02 ; C22C38/04 ; C22C38/14 ; C22C38/06 ; C21D8/02 ; C23C2/06 ; C21D9/46 ; C22C38/00 ; C23C2/28 ; C23C2/02 ; C22C38/12
摘要：
This high-strength steel sheet includes: in terms of percent by mass, 0.03 to 0.10% of C; 0.01 to 1.5% of Si; 1.0 to 2.5% of Mn; 0.1% or less of P; 0.02% or less of S; 0.01 to 1.2% of Al; 0.06 to 0.15% of Ti; and 0.01% or less of N; and contains as the balance, iron and inevitable impurities, wherein a tensile strength is in a range of 590 MPa or more, and a ratio between the tensile strength and a yield strength is in a range of 0.80 or more, a microstructure includes bainite at an area ratio of 40% or more and the balance being either one or both of ferrite and martensite, a density of Ti(C,N) precipitates having sizes of 10 nm or smaller is in a range of 1010 precipitates/mm3 or more, and a ratio (Hvs/Hvc) of a hardness (Hvs) at a depth of 20 μm from a surface to a hardness (Hvc) at a center of a sheet thickness is in a range of 0.85 or more.