| 摘要 |
PROBLEM TO BE SOLVED: To provide a steel sheet for a two-piece contoured can, which can be bulged at a circumferential tensile distortion of 10% or higher, after having been deep-drawn, and to provide a manufacturing technology therefor. SOLUTION: The steel sheet includes 0.0020 mass% or less C, 0.05 mass% or less Si, 0.7 mass% or less Mn, 0.02 mass% or less P, 0.010 mass% or less S, 0.100 mass% or less Al, 0.0030 mass% N and 0.003-0.03 mass% or less Nb. The manufacturing method comprises the steps of: hot-rolling the above steel slab at a finish rolling temperature of 850°C or higher; winding it up at 650°C or higher; cold-rolling it at a rolling reduction of 85% or higher; then, annealing it in the temperature range between a recrystallization temperature and 850°C; subsequently temper-rolling it at a rolling reduction of 5% or lower. Thereby, the steel sheet acquires a ferrite structure consisting of grains with sizes of 15μm or smaller; an r-value of 1.8 or larger by average; an anisotropy of the r-value (Δr) in a range between minus 0.10 and plus 0.10; elongations of 40% or larger in any of a rolling direction, a transeverse direction and a direction angled at 45 degrees; and an aging index (AI) of 0.0 MPa or lower. COPYRIGHT: (C)2006,JPO&NCIPI
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