| 摘要 |
PROBLEM TO BE SOLVED: To provide a cold-rolled steel sheet having excellent workability and shape fixability, a process for production of same, and a backlight chassis by appropriate control of minor components and r value. SOLUTION: Disclosed is a cold-rolled steel sheet which is characterized by containing C: 0.0010 to 0.0030%, Si: 0.05% or less, Mn: 0.1 to 0.3%, P: 0.05% or less, S: 0.02% or less, Al: 0.02 to 0.10%, N: 0.005% or less, and Nb: 0.010 to 0.030% with the balance being Fe and unavoidable impurities and which is characterized in that the r value in the longitudinal and crosswise directions are each 1.0 to 1.6 and that the mean El<SB>m</SB>of elongations in the longitudinal direction, in the direction at 45° to the longitudinal direction and in the crosswise direction is 40% or above, with the proviso that El<SB>m</SB>=(El<SB>L</SB>+2×El<SB>D</SB>+El<SB>C</SB>)/4El<SB>L</SB>: wherein El<SB>L</SB>: elongation in the longitudinal direction, El<SB>D</SB>: elongation in the direction at 45° to the longitudinal direction, and El<SB>C</SB>: elongation in the crosswise direction. COPYRIGHT: (C)2010,JPO&INPIT |
