| 摘要 |
The invention provides a high strength steel sheet which exhibits excellent phosphatability and corrosion resistance after electro-coating even in the case where the steel sheet has a high Si content, and a method for manufacturing such steel sheets. The method includes continuous annealing of a steel sheet which includes, in terms of mass%, C at 0.01 to 0.18%, Si at 0.4 to 2.0%, Mn at 1.0 to 3.0%, Al at 0.001 to 1.0%, P at 0.005 to 0.060% and S at ‰¤ 0.01%, the balance being represented by Fe and inevitable impurities, in such a manner that the dew point of the atmosphere is controlled to become not more than - 45°C during the course of soaking when the annealing furnace inside temperature is in the range of not less than 820°C and not more than 1000°C as well as that the dew point of the atmosphere is controlled to become not more than -45°C during the course of cooling when the annealing furnace inside temperature is in the range of not less than 750°C. |
