| 摘要 |
The present invention provides a steel sheet with excellent cold workability during forming and a process for producing the steel sheet. The steel sheet according to the present invention has a composition which contains, in terms of mass%, 0.10-0.40% C, 0.01-0.30% Si, 0.30-1.00% Mn, 0.0001-0.020% P, 0.0001-0.010% S, and 0.001-0.10% Al, with the remainder comprising Fe and unavoidable impurities, and is characterized in that (a) the ratio of the number of carbide grains present at the ferrite grain boundaries to the number of carbide grains present inside the ferrite grains exceeds 1, (b) the ferrite grains have a diameter of 5-50 µm, (c) the in-plane r value anisotropy |Δr| is 0.2 or less, (d) the Vickers hardness is 100-150 HV, and (e) in the part of the steel sheet which is located at a depth of 1/2 the sheet thickness, the random intensity ratio for the {311}<011> orientation is 3.0 or less. |
