HIGH STRENGTH AND HIGH TOUGHNESS STEEL BAR FOR EARTHQUAKE PROOF DAMPER EXCELLENT IN LOW CYCLE FATIGUE CHARACTERISTIC ND PRODUCING METHOD THEREFOR

摘要

PROBLEM TO BE SOLVED: To provide a steel bar for an earthquake proof damper in which the increase of strength for increasing energy absorption and the improvement of the low cycle fatigue life are made consistent and moreover excellent in low temperature toughness and to provide a producing method therefor.;SOLUTION: This high strength and high toughness steel bar for an earthquake proof damper excellent in low cycle fatigue characteristics has a composition containing, by mass, 0.02 to 0.15% C, 0.01 to 1.5% Si, 0.2 to 3.0% Mn, 0.001 to 0.3% Al and 0.001 to 0.02% N and, if required, containing other elements, and in which carbon equivalent is 0.3 to 0.8%. Moreover, this steel can be product by performing heat treatment to 850 to 1,100°C and hot-forming or performing normalizing treatment so as to be heated at 850 to 1,100°C after hot forming.;COPYRIGHT: (C)2001,JPO