TOUGH STEEL FOR ANCHOR HEAD HAVING HIGH SURFACE HARDNESS AND SUPERIOR TOUGHNESS AT LOW TEMPERATURE

摘要

PURPOSE:To provide tough steel for an anchor head consisting of prescribed percentages of C, Si, Mn, P, S, Ni, Cr, Mo, Cu and Sn and the balance Fe with inevitable impurities and having high surface hardness and superior toughness at low temp. CONSTITUTION:This tough steel for an anchor head consists of, by weight, 0.36-0.40% C, 0.15-0.35% Si, 0.60-0.90% Mn, =0.015% P, =0.008% S, 1.80- 2.20% Ni, 0.80-1.20% Cr, 0.25-0.35% Mo, =0.15% Cu, =0.015% Sn and the balance Fe with inevitable impurities. Since the steel has high surface hardness and superior toughness at low temp., it is most suitable for use as a steel material for a prestressed system anchor head used in a reactor container made of prestressed concrete for a nuclear power plant.