发明名称 |
THICK-WALLED HIGH-STRENGTH HOT ROLLED STEEL SHEET HAVING EXCELLENT HYDROGEN INDUCED CRACKING RESISTANCE AND MANUFACTURING METHOD THEREOF |
摘要 |
A thick-walled high-strength hot rolled steel sheet having excellent hydrogen induced cracking resistance which is preferably used as a raw material for a high-strength welded steel pipe of X65 grade or more and a method of manufacturing the thick-walled high-strength hot rolled steel sheet are provided. The composition of the thick-walled high-strength hot rolled steel sheet contains by mass % 0.02 to 0.08% C, 0.50 to 1.85% Mn, 0.03 to 0.10% Nb, 0.001 to 0.05% Ti, 0.0005% or less B in such a manner that (Ti+Nb/2)/C<4 is satisfied or also contains one or two kinds or more of 0.010% or less Ca, 0.02% or less REM, and Fe and unavoidable impurities as a balance. The steel sheet has the structure formed of a bainitic ferrite phase or a bainite phase. Surface layer hardness is 230HV or less in terms of Vickers hardness. |
申请公布号 |
US2012018056(A1) |
申请公布日期 |
2012.01.26 |
申请号 |
US201013146751 |
申请日期 |
2010.01.29 |
申请人 |
NAKAGAWA KINYA;KAMI CHIKARA;JFE STEEL CORPORATION |
发明人 |
NAKAGAWA KINYA;KAMI CHIKARA |
分类号 |
C21D8/02;C21D11/00;C22C38/02;C22C38/04;C22C38/06;C22C38/08;C22C38/12;C22C38/14;C22C38/16;C22C38/42;C22C38/44;C22C38/46;C22C38/48;C22C38/50;C22C38/54;C22C38/58 |
主分类号 |
C21D8/02 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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