PRODUCTION OF HOT ROLLED FERRITIC STAINLESS STEEL STRIP EXCELLENT IN TOUGHNESS AT LOW TEMPERATURE

摘要

PURPOSE: To produce a hot rolled ferritic stainless steel strip excellent in toughness at low temp. as well as in heat resistance at a low cost by subjecting a hot rolled plate, having a specific composition consisting of C, Si, Mn, Cr, Nb, Ti, Cu, N, Al, O, and Fe and also having specific plate thickness, to water cooling and then to coiling at specific temp. ;CONSTITUTION: A ferritic stainless steel, having a composition consisting of, by mass, ≤0.03% C, 0.80-1.20% Si, 0.60-1.50% Mn, 13.5-15.5% Cr, 0.20-0.80% Nb, ≤0.1% Ti, 0.02-0.30% Cu, ≤0.03% N, ≤0.05% Al, ≤0.012% O, and the balance Fe with inevitable impurities at manufacture, is hot-rolled at ≥800°C to 4.5-9.0mm final plate thickness. Then, the resulting hot rolled plate is immediately water-cooled to avoid the precipitation of Laves phase and coiled. At this time, coiling temp. T is regulated so that it satisfies the inequality, t×T≤3600 [where (t) is the thickness of the hot rolled plate].;COPYRIGHT: (C)1996,JPO