| 摘要 |
<p>PURPOSE: A cold-rolled steel sheet with excellent formability and heat resistance and a manufacturing method thereof are provided to obtain various workabilities including elongation flangeability, bendability, and deep-drawability of a cold-rolled steel sheet. CONSTITUTION: A cold-rolled steel sheet comprises 0.002-0.005weight% of C, 0.05-0.08weight% of Ti, 0.02-0.20weight% of Sn, 0.10-0.55weight% of Mn, 0.01-0.10weight% of Al, 0.003-0.020weight% of P, 0.002-0.006weight% of N, 0.015weight% or less of S, and the remaining amount of Fe and inevitable impurities, where the atomic ratio of Ti and C, Ti/C, is 1.6-4.0. The cold-rolled steel sheet comprises equiaxed ferrite and acicular ferrite structures. [Reference numerals] (a) Invented material 3; (b) Comparison material 10</p> |
