| 摘要 |
The present invention provides a steel sheet having excellent cold-forming properties and post-heat treatment ductility, and a manufacturing method therefor. A steel sheet according to the present invention has a component composition comprising, in terms of mass%, 0.10-0.40% C, 0.30-1.00% Si, 0.30-1.00% Mn, 0.001-0.10% Al, 0.0001-0.02% P and 0.0001-0.01% S, with the remainder being Fe and unavoidable impurities. The steel sheet is characterized in that the ratio (B/A) of the number (B) of carbides at the ferrite grain boundaries to the number (A) of carbides within the ferrite grains is greater than 1, the ferrite grain diameter is 5-50 μm, inclusive, the average particle diameter of the carbides is 0.4-2.0 μm, inclusive, the pearlite surface area ratio is 6% or less, and the Vickers hardness is 120-170 HV, inclusive. |
