| 摘要 |
The present invention provides high strength hot rolled steel plate superior in stretch flange formability and fatigue characteristics comprising steel plate containing C: 0.03 to 0.20%, Si: 0.08 to 1.5%, Mn: 1.0 to 3.0%, P: 0.05% or less, S: 0.02% or more, N: 0.0005 to 0.01%, acid soluble Al: 0.01% or less, acid soluble Ti: less than 0.008%, and a total of one or both of Ce or La: 0.0005 to 0.04%, having a balance of iron and unavoidable impurities, having a number ratio of stretched inclusions present in the steel plate having a circle equivalent diameter of 1 µm or more and a long axis/short axis of 5 or more of 20% or less, and having a (Ce+La)/S ratio of 0.1 to 70. |
