摘要 |
PROBLEM TO BE SOLVED: To provide a method for producing a hot dip galvanized steel sheet having a fine surface appearance free from unplating and having excellent plating adhesion with an Si-containing high strength steel sheet as a base material, and to provide a method for producing a hot dip galvannealed steel sheet having a fine surface appearance free from unplating, and having excellent plating adhesion. SOLUTION: When a steel sheet containing, as chemical components, by mass, 0.05 to 0.30% C, 1.0 to 3.0% Si, 0.5 to 3.0% Mn, 0.01 to 3.0% Al, 0.001 to 0.01% S and 0.001 to 0.1% P, and the balance Fe with inevitable impurities is hot-dip galvanized, the temperature of the steel sheet is raised in an atmosphere comprising 0.01 to 1 vol% O<SB>2</SB>and including a dew point of≤0°C, and the steel sheet is heated to a temperature within the range of 750 to 900°and is thereafter, or is heated and held and is thereafter, cooled and is subjected to hot dip galvanizing. COPYRIGHT: (C)2010,JPO&INPIT |