| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing a cold-rolled steel sheet exhibiting excellent chemical conversion processability and excellent corrosion resistance after coating in harsh corrosive environments such as in a warm salt water immersion test or a compound cyclic corrosion test; a cold rolled steel sheet manufactured by the method; and automobile members prepared using the steel sheets. <P>SOLUTION: A cold rolled steel sheet preferably containing 0.5-3.0 mass% of Si, and subjected to continuous annealing after being cold-rolled is pickled to remove an Si-containing oxide layer on the surface layer of the steel sheet, and then pickled again, thereby restricting the surface coverage of an iron-based oxide on the surface of the steel sheet to ≤40%, more preferably, restricting the maximum thickness of the iron-based oxide to ≤150 nm. <P>COPYRIGHT: (C)2012,JPO&INPIT |
