EARTHQUAKE-PROOF DAMPER STEEL FOR WITH A LOW YIELD RATIO, A HIGH ELONGATION RATIO, AND EXCELLENT LOW-TEMPERATURE IMPACT CHARACTERISTIC AND A MANUFACTURING METHOD THEREOF

摘要

PURPOSE: Earthquake-proof damper steel for with a low yield ratio and a manufacturing method thereof are provided to improve the earthquake-proof performance of a building by providing a low yield ratio, a high elongation ratio, and excellent low-temperature impact characteristic.;CONSTITUTION: Earthquake-proof damper steel comprises 0.01-0.05 weight% of C, 0.05-0.1 weight% of Si, 0.1-0.5 weight% of Mn, 0.015 weight% or less of P, 0.01 weight% or less of S, 0.03 weight% or less of Ti, 40ppm or less of N, and the remaining amount of Fe and inevitable impurities. The earthquake-proof damper steel has a tensile strength of 250-280MPa, a yield strength of 160-190MPa, an elongation ratio of 50-52 weight%, and a 0°C impact toughness of 200-250J.;COPYRIGHT KIPO 2013;[Reference numerals] (AA) Start; (BB) End; (S110) Slab reheating(SRT: 1150-1250°C); (S120) Hot rolling(FDT: 950-1050°C); (S130) Cooling(Air-cooling)