| 摘要 |
PROBLEM TO BE SOLVED: To provide a cold rolled steel sheet having excellent workability in a stable state and to provide an advantageous manufacturing method thereof.SOLUTION: A cold rolled steel sheet has a composition containing, by mass, more than 0.010 and 0.035% or less C, 0.1% or less Si, 0.35% or less Mn, 0.035% or less P, 0.02% or less S, 0.0060% or less N, and 0.005-0.1% Al, and satisfying the relation of [%Mn]/[%Al]<20, with the remainder comprising Fe and unavoidable impurities. The cold rolled steel sheet is characterized in that the ferrite grain size in the steel is 5 μm or more, and 50% or more of the precipitating cementite precipitates in the ferrite grain boundary. |
