| 摘要 |
<p>The present invention relates to a composition structure steel sheet used in a structure member of a vehicle and, more specifically, relates to a composition structure steel sheet with superior bake hardenability; and a method to manufacture the same. An embodiment of the present invention provides a composition structure steel sheet with superior bake hardenability comprising: 0.06-0.13 wt% of carbon (C); 0.005-0.5 wt% of silicon (Si); 2.5-3.2 wt% of manganese (Mn); 0.01-0.06 wt% of soluble aluminum (Sol.Al); 0.1-0.5 wt% of chrome (Cr); 0.0005-0.005 wt% of boron (B); 0.005-0.05 wt% of antimony (Sb); 0.001-0.05 wt% of phosphorus (P); 0.001-0.007 wt% of sulfur (S); 0.001-0.007 wt% of nitrogen (N); 0.01-0.05 wt% of titanium (Ti); 0.01-0.05 wt% of niobium (Nb); the remnant Fe and other inevitable impurities wherein a refined structure consists of 3-10% of ferrite, 1-3% of martensite, and the remnant bainite based on an area fraction.</p> |
