| 摘要 |
<p>PURPOSE: A high strength steel sheet with superior formability for hydroforming and a manufacturing method thereof are provided to improve the workability and formability of a high strength steel sheet, thereby enabling application to a high strength steel pipe. CONSTITUTION: A method for manufacturing a high strength steel sheet with superior formability for hydroforming comprises a step of hot rolling a slab to an FDT(Finishing Delivery Temperature) of 870-910°C(S110) and a step of cooling and coiling the hot rolled sheet at a CT of 620-660°C(S120). The slab comprises carbon of 0.05-0.09 weight%, silicon of 0.030 weight% or less, manganese of 0.50-0.80 weight%, aluminum of 0.020-0.050 weight%, nitrogen of 40PPm or less, and iron and inevitable impurities of the remaining amount.</p> |
