HIGH-CORROSION RESISTANCE COLD-ROLLED STEEL SHEET WITH EXCELLENT WORKABILITY AND TARNISH RESISTANCE AND A MANUFACTURING METHOD THEREOF WHICH FORMS Cu-BASED SULFIDES ON THE STEEL SHEET SURFACE

摘要

PURPOSE: A high-corrosion resistance cold-rolled steel sheet with excellent workability and tarnish resistance and a manufacturing method thereof are provided to reduce the content of expensive alloy elements and optimize steel components and process conditions, thereby reducing manufacturing costs.;CONSTITUTION: A high-corrosion resistance cold-rolled steel sheet comprises 0.001-0.004wt.% of C, 0.05-0.35wt.% of Sn, 0.07-0.55wt.% of Mn, 0.01-0.10wt.% of Al, 0.0005-0.0020wt.% of B, 0.1-0.4wt.% of Cu, 0.003-0.020wt.% of P, 0.001-0.004wt.% of N, 0.015wt.% or less of S, and the remaining amount of Fe and inevitable impurities, where the atomic ratio of B to N is 0.5-1.5. A B-based nitrided precipitate is formed in the cold-rolled steel sheet.;COPYRIGHT KIPO 2013