| 摘要 |
PURPOSE: A cold-rolled steel sheet and a manufacturing method thereof are provided to control a ferrite matrix structure by controlling heating speed in the direct fire furnace section of an annealing heat treatment process, thereby obtaining excellent bending properties. CONSTITUTION: A method for manufacturing a cold-rolled steel sheet includes the following steps of: finish hot-rolling a slab plate at a finishing delivery temperature of 850-950°C; cooling the slab plate at a coiling temperature of 550-650°C and coiling the cooled slab plate; cold-rolling the coiled slab after acid dipping process; after rapidly heating the cold-rolled plate at a temperature of 630-680°C and a speed of 20-40°C/sec in the direct fire furnace section. |
