MANUFACTURE OF HIGH TENSILE HOT ROLLED STEEL STRIP CONTAINING VANADIUM

摘要

PURPOSE:To manufacture the titled steel strip with superior strength, ductility and toughness by holding a continuously cast slab of a low carbon steel consisting of Si, Mn, S, Al, V, N and the balance essentially Fe at a specified temp., hot rolling the slab, and coiling the resulting strip after rapid cooling. CONSTITUTION:A steel slab consisting of, by weight, 0.02-0.15% C, =1.50% Si, 0.5-2.20% Mn, =0.010% S, 0.005-0.020% sol.Al, 0.02-0.30% V, 0.0050- 0.0200% N and the balance Fe with inevitable impurities is manufactured by a continuous casting method. The slab is held at the A3 point - 1,180 deg.C for a fixed time and hot rolled at =1,100 deg.C and =70% draft. After finishing the rolling at 850-680 deg.C, the resulting strip is rapidly cooled to 650-500 deg.C at =3 deg.C/sec cooling rate and coiled at the temp.