POSCO Holdings Inc.
High-strength hot-dip galvanized steel sheet having excellent plating surface quality and adhesion, and method of manufacturing the same

Abstract:

Provided is a method of manufacturing a hot-dip galvanized steel sheet. According to an aspect of the present invention, the method may include preparing a base steel sheet, forming a iron (Fe)-plated layer on the prepared base steel sheet, oxidation heating the steel sheet having the Fe-plated layer formed thereon at a temperature ranging from 600.degree. C. to 800.degree. C., maintaining the heated steel sheet at a temperature ranging from 750.degree. C. to 900.degree. C. for 5 seconds or more in a reducing atmosphere with a dew point of between -30.degree. C. to 5.degree. C. including 20 ppm or less of oxygen, 1 vol % to 20 vol % of H.sub.2, and N.sub.2 as well as unavoidable gases as a remainder, cooling the maintained steel sheet, and plating the cooled steel sheet by dipping in a hot-dip galvanizing bath.