| 摘要 |
There is provided a high-strength hot rolled steel sheet excellent in phosphatability, wherein a maximum depth (Ry) of pits and bumps, existing on a surface thereof, is not less than 10 μm, and an average interval (Sm) of the pits and the bumps is not more than 30 μm, meeting either a requirement for a load length ratio (tp40) of the pits and the bumps on the surface at not more than 20%, or a requirement for a difference between a load length ratio (tp60) and the load length ratio (tp40), at not less than 60%, or both thereof. The high-strength hot rolled steel sheet is capable of exhibiting stable and excellent phosphatability even if Mo highly effective for reinforcement in strength is added thereto in expectation of a higher strength. |
