| 摘要 |
<p>PURPOSE: A cold-rolled steel sheet having excellent heat resistance and discoloration resistance and a manufacturing method thereof are provided to prevent yield point elongation by enhancing aging resistance through solid solution precipitation. CONSTITUTION: A cold-rolled steel sheet comprises C of 0.01-0.10%, Mn of 0.10-0.35%, P of 0.003-0.020%, Al of 0.02-0.08%, B of 0.001-0.003%, Sn of 0.05-0.25%, N of 0.002-0.006%, Ti of 0.07-0.15%, S of 0.015% or less, and Fe and inevitable impurities of the remaining amount. The atomic ratio of Ti and C, Ti/C, is 0.3-0.7 and the atomic ratio of B and N, B/N, is 0.5-1.5.</p> |
