| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a method for producing a hot-dip galvanized steel sheet excellent in plating suitability and elongation properties. <P>SOLUTION: The method include: preparing a steel sheet having a composition containing, by mass,≤0.04% C,≤0.05% Si, 0.05-0.5% Mn,≤0.01% S,≤0.05% P,≤0.08% sol.Al, and≤0.01% N; heating the steel sheet in a direct heating zone of a direct heating system; further performing the reduction of a sheet surface and annealing in a reducing atmosphere in a reducing zone; and then dipping the sheet in a hot-dip galvanizing bath to galvanize. At that time, the direct heating zone is divided into 4 zones of the first to fourth zones, and the air ratios are made to be 0.70-0.90 in the first zone, 0.70-0.90 in the second zone, 0.70-0.90 in the third zone and 0.70-0.85 in the fourth zone. <P>COPYRIGHT: (C)2012,JPO&INPIT</p> |
