| 摘要 |
A high-strength hot-rolled steel sheet with excellent burring workability, and a production method thereof are provided. This high-strength hot-rolled steel sheet with excellent burring workability has a composition which includes, in mass%, C: 0.06%-0.13%, Si: less than 0.5%, Mn: greater than 0.5% and less than or equal to 1.4%, P: 0.05% or less, S: 0.005% or less, N: 0.01% or less, Al: 0.1% or less, Ti: 0.05%-0.25% and V: greater than 0.15% and less than or equal to 0.4%, such that S, N, Ti and V satisfy Ti* + V ≧ 0.35 (here, Ti*=Ti-N×(48/14)-S×(48/32), and S, N, Ti and V represent the content (in mass%) of each element), with the remainder consisting of Fe and unavoidable impurities, and is of a material in which the ferrite phase fraction exceeds 90%, carbides containing Ti are precipitated, and 70% or more of said carbides have a particle diameter of less than 9nm. |
