| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for manufacturing, stably and in a short period of time, a hot-dip galvanized steel sheet having excellent press formability.SOLUTION: The method includes the steps of: hot-dip galvanizing a steel sheet; temper-rolling the steel sheet; subsequently making the steel sheet brought into contact with an acidic solution having a pH buffer action and containing an iron masking agent; holding the steel sheet for 1 to 60 seconds after the contact treatment; and washing the steel sheet with water. Thereby, a zinc based oxide layer is formed on a surface of the plated steel sheet. In the iron masking agent, it is preferable that a logarithm of the formation constant of a complexation reaction with Fe(II) is 3.0 or more, and that the logarithm of the formation constant of the complexation reaction with Fe(II) is higher than a logarithm of a formation constant of the complexation reaction with Zn(II). |
