Hot-dip galvanizing treatment method, production method of alloyed hot-dip galvanized steel sheet using the hot-dip galvanizing treatment method, production method of hot-dip galvanized steel sheet using the hot-dip galvanizing treatment method, alloyed hot-dip galvanized steel sheet and hot-dip galvanized steel sheet

摘要

A hot-dip galvanizing treatment method capable of suppressing the occurrence of surface defects such as dross defects, non-plating, and surface scratches is provided. The hot-dip galvanizing treatment method according to the present disclosure is a hot-dip galvanizing treatment method used for producing a hot-dip galvanized steel sheet or an alloyed hot-dip galvanized steel sheet, and using a hot-dip galvanizing bath containing Al. This hot-dip galvanizing treatment method includes a concentration maintaining step. In the concentration maintaining step, when the free Fe concentration in the hot-dip galvanizing bath is defined as X (mass%) and the free Al concentration in the hot-dip galvanizing bath is defined as Y (mass%), the free Fe concentration in the hot-dip galvanizing bath And the free Al concentration in a range satisfying the formulas (1) to (4).