| 摘要 |
According to an embodiment of the present invention, a hot pressed member having superior ductility and impact toughness, comprises: 0.04-0.12 wt% of carbon (C); 0.35-1.3 wt% of silicon (Si); 0.6-1.5 wt% of manganese (Mn); 0.01-0.08 wt% of aluminum (Al); 0.03-0.1 wt% of titanium (Ti); 0.015-0.1 wt% of molybdenum (Mo); 0.03 wt% or less of phosphorus (P); 0.01% or less of sulfur (S); and 0.01 wt% of nitrogen (N); at least one kind of one selected from a group consisting of 0.01 wt% or less of chromium (Cr), 0.1 wt% or less of copper (Cu), 0.1 wt% or less of vanadium (V), 0.1 wt% or less of zirconium (Zr), 0.1 wt% or less of niobium (Nb) and 0.1 wt% or less of nickel (Ni); and the remaining consisting of iron (Fe) and inevitable impurities. Moreover, the hot pressed member may have a microstructure where 75% or more of ferrite, 25% or less of martensite or 20% or less of bainite are mixed. The hot stressed member has the above described composition and microstructure, thereby improving impact toughness and also securing superior ductility and uniform strength. |
