| 摘要 |
<p>Disclosed are a high-strength molten zinc-plated steel sheet having a low YP value, good stretch flangeability and excellent corrosion resistance and a process for producing the steel sheet. The steel sheet comprises 0.015 to 0.10 mass% exclusive of C, 0.5 mass% or less of Si, 1.0 to 1.9 mass% inclusive of Mn, 0.015 to 0.050 mass% inclusive of P, 0.03 mass% or less of S, 0.01 to 0.5 mass% inclusive of sol. Al, 0.005 mass% or less of N, less than 0.40 mass% of Cr, 0.005 mass% or less of B, less than 0.15 mass% of Mo, 0.4 mass% or less of V and less than 0.020 mass% of Ti, wherein the components meet the requirements represented by the following formulae: 2.2≤[Mneq]≤3.1, [%Mn]+3.3[%Mo]≤1.9, and ([%Mn]+3.3[%Mo])/ (1.3[%Cr]+8[%P]+150B*) < 3.5. The steel structure comprises 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> |
