MANUFACTURE OF HIGH STRENGTH PC STEEL WIRE OR BAR HAVING SUPERIOR RELAXATION CHARACTERISTIC

摘要

PURPOSE:To simply manufacture a high strength PC steel wire or bar having superior relaxation characteristics by drawing a steel material having a specified composition consisting of C, Si, Mn, Cr, N and Fe at a proper temp. and a high reduction of area. CONSTITUTION:A steel material consisting of, by weight, 0.50-0.70% C, 0.20-1.40% Si, 0.60-1.50% Mn, 0.60-1.20% Cr, 60-150ppm N and the balance essentially Fe is drawn at 250-450 deg.C and =20% reduction of area. Thus, a high strength PC steel wire or bar having satisfactory relaxation characteristics is obtd. with small drawing force in only one heating stage.