This research aims at clarifying the effects of cold press-bending on the mechanical properties of steel plates in order to reason the fact that brittle fracture has been witnessed in recent experiments of steel box-columns produced by cold press-forming. The changes in mechanical properties were investigated in the press-bent corner and its welded joint to a diaphragm plate. It was found that the cold press-bending causes the increase in strength, the decrease in ductile elongation capacity, and the remarkable reduction in impact energy absorption in the outer surface. However, these unfavorable mechanical properties related to brittle fracture were completely recovered by postheating of 850℃-normalizing.
