| 摘要 |
A practical high-workability steel sheet for three-piece welded cans contains, in percent by mass, more than 0.0015% to 0.0030% of carbon, 0.10% or less of silicon, 0.20% to 0.80% of manganese, 0.001% to 0.020% of phosphorus, 0.001% to 0.020% of sulfur, more than 0.040% to 0.100% of aluminum, 0.030% or less of nitrogen, and 0.0002% to 0.0050% of boron, the balance being iron and incidental impurities, and has a tensile strength of 400 MPa or more in a direction perpendicular to a rolling direction and a fracture elongation of 15% or more in the direction perpendicular to the rolling direction. This steel sheet can be produced by hot-rolling a steel having the above composition at a finish rolling temperature of the Ar 3 transformation temperature to 960°C and a coiling temperature of 560°C to 750°C; subjecting the steel sheet to first cold rolling at a rolling reduction of 89% to 93%; annealing the steel sheet at 600°C to 790°C; and subjecting the steel sheet to second cold rolling at a rolling reduction of more than 6.0% to less than 10.0%. |
