MANUFACTURE OF DIRECTLY-SOFTENED STEEL WIRE ROD

PURPOSE:To carry out the direct softening treatment of a steel wire rod by utilization of hot-rolling heat, by successively applying intermediate rolling, the primary finish rolling, the secondary finish rolling, and slow cooling to a roughed steel wire rod under specific conditions. CONSTITUTION:After roughed, the steel wire rod is subjected to intermediate rolling at a temp. in the temp. region of 700-850 deg.C at 20-80% draft. Subsequently, this wire rod is subjected to the primary finish rolling at a temp. in the temp. region of 700-850 deg.C to undergo acceleration of transformation into ferrite-pearlite phase as well as of refining of austenitic grain size, which is further subjected to the secondary finish rolling at a temp. in the temp. region of 650-750 deg.C at 20-60% draft, followed by slow cooling at