发明名称 |
HIGH-STRENGTH HOT-DIPPED GALVANIZED STEEL SHEET AND HIGH-STRENGTH ALLOYED HOT-DIPPED GALVANIZED STEEL SHEET,EACH HAVING TENSILE STRENGTH OF 980 MPA OR MORE,EXCELLENT PLATING ADHESION,EXCELLENT FORMABILITY AND EXCELLENT BORE EXPANDING PROPERTIES ,AND METHOD FOR PRODUCING SAME |
摘要 |
Provided is a high-strength hot-dip galvanized steel sheet having excellent plating adhesion, formability, and hole expandability with an ultimate tensile strength of 980 MPa or more, the hot-dip galvanized steel sheet comprising a hot-dip galvanized layer formed on a surface of a base steel sheet. The base steel sheet contains, by mass%, C: 0.05% to 0.4%; Si: 0.01% to 3.0%; Mn: 0.1% to 3.0%; Al: 0.01 to 2.0%; in which Si + Al > 0.5%, P: limited to 0.04% or less; S: limited to 0.05% or less; N: limited to 0.01% or less; and a balance including Fe and inevitable impurities, a microstructure of the base steel sheet contains 40% or more by total volume fraction of martensite and bainite, 8% or more by volume fraction of residual austenite, and a balance of the microstructure being ferrite or ferrite and 10% or less by volume fraction of pearlite. The martensite contains 10% or more by total volume fraction of two or more kinds of three kinds of martensites (1), (2), and (3), and the hot-dip galvanized layer contains less than 7 mass% of Fe. |
申请公布号 |
ZA201402970(B) |
申请公布日期 |
2015.04.29 |
申请号 |
ZA20140002970 |
申请日期 |
2014.04.23 |
申请人 |
NIPPON STEEL & SUMITOMO METAL CORPORATION |
发明人 |
WAKABAYASHI,CHISATO;FUJITA,NOBUHIRO;AZUMA,MASAFUMI;SANO,KOHICHI |
分类号 |
C21D;C22C;C23C |
主分类号 |
C21D |
代理机构 |
|
代理人 |
|
主权项 |
|
地址 |
|