| 摘要 |
<p>PURPOSE: A cold-rolled steel sheet having excellent heat resistance and a manufacturing method thereof are provided to manufacture a cold-rolled steel sheet at low costs by optimizing steel components and processing conditions while employing middle-low carbon and reducing the addition of expensive alloy elements. CONSTITUTION: A method for manufacturing a cold-rolled steel sheet comprises the steps of: heating and hot-rolling steel slab, which comprises C of 0.01-0.10%, Mn of 0.3-0.6%, P of 0.03-0.08%, Al of 0.02-0.08%, B of 0.001-0.003%, W of 0.05-0.30%, N of 0.002-0.010%, Ti of 0.07-0.15%, S of 0.015% or less, and Fe and inevitable impurities of the remaining amount, coiling and cold-rolling the hot-rolled steel sheet, annealing the cold-rolled steel sheet at a temperature of 800°C or greater, and cooling the annealed steel sheet at a cooling speed of 40°C/sec or greater.</p> |
