| 摘要 |
PURPOSE:To easily manufacture a hot dip galvanized steel sheet having superior press workability after powder coating at a low cost by subjecting a dead soft steel having a specified compsn. consisting of C, Si, Mn, S, N, Ti and Fe to specified hot rolling. CONSTITUTION:A steel consisting of, by weight, 0.002-0.03% C, <=0.10% Si, 0.05-0.45% Mn, <=0.010% S, <=0.006% N, <=0.10% Ti and the balance Fe with inevitable impurities and having 3.0-10.0 atomic ratio of total Ti* except Ti in the form of TiN to C[Ti*/C] is hot rolled at <=1,100 deg.C rough rolling finish temp., >=20sec interval between the end of rough rolling and the beginning of finish rolling, >=40% total draft in several stands in the latter stage of a finish rolling mill and 650-730 deg.C coiling temp. The hot rolled sheet is pickled, cold rolled and hot dip galvanized. Thus, a hot dip galvanized steel sheet having satisfactory adhesion and superior workability is obtd. The yield elongation of the steel sheet is regulated to about <=2% even when heat treated at high temp. after powder coating.
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