| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a high-strength molten zinc-plated steel sheet having low YP value, good stretch flange property and excellent corrosion resistance and a process for producing the steel sheet. <P>SOLUTION: The steel sheet has a composition containing, by mass, >0.015 to <0.10% C,≤0.5% Si, 1.0 to 1.9% Mn, 0.015 to 0.050% P,≤0.03% S, 0.01 to 0.5% sol.Al,≤0.005% N, <0.40% Cr,≤0.005% B, <0.15% Mo,≤0.4% V and <0.020% Ti, and satisfying 2.2≤[Mneq]≤3.1 and [%Mn]+3.3[%Mo]≤1.9, and ([%Mn]+3.3[%Mo])/(1.3[%Cr]+8[%P]+150B<SP>*</SP>)<3.5. The steel structure has ferrite and a second phase, wherein the second phase is contained at a ratio of 2 to 12% by volume, and 1 to 10% by volume of martensite and 0 to 5% by volume of remainingγare contained as the second phase. <P>COPYRIGHT: (C)2011,JPO&INPIT</p> |
