DRAWABLE HIGH STRENGTH STEEL SHEET HAVING SUPERIOR FATIGUE PROPERTY OF SPOT-WELDING POINT AND ANTI-POWDERING AND METHOD FOR MANUFACTURING THE SAME

摘要

for the automotive, consumer products, such as being used for building materials , Spot Welding fatigue characteristics and excellent powder processing ringseong . the high strength steel sheet and a manufacturing method thereof are provided ; in the steel sheet is by weight %, C: 0.01 ~ 0.20%, Si: less than 0.10%, Mn: 0.1 ~ 0.6%, P: 0.03% or less, S: less than 0.020%, Sol.Al: 0.01 ~ 0.20%, Mo: 0.01 ~ 0.10%, Cu: 0.01 ~ 0.20%, ; N: 0.005 ~ 0.015%, remainder of Fe and other unavoidable and the composition as an impurity , ; the C, Si, Mn, P, Mo, Cu, N , the following conditions , ; 29.1 + 98C (%) + 4.0Mn (%) + 9.1Si (%) + 82P (%) + 3.5Mo (%) + 2.9Cu (%) + 410N (%) 45 and satisfies , ; the Al and N contents , the following relationship , ; 3.1 is satisfied Al / N 6.0. ; According to the present invention , the blood of spot Welding characteristics and powder ringseong excellent tensile strength 45kg / than treating high strength can provide a steel sheet .