METHOD FOR MANUFACTURING DROSS-FREE GALVANNEALED STEEL SHEET

摘要

PURPOSE: A method for manufacturing dross-free galvannealed steel sheet is provided to effectively manufacture galvannealed steel sheet having superior surface quality by optimally controlling composition and conditions of plating pot for enabling dross-free operation to be performed. CONSTITUTION: In a process for manufacturing a galvannealed steel sheet by dipping a steel sheet into a galvanizing pot and charging the steel sheet coming out of the plating pot into an alloying furnace, the method is characterized in that the plating pot is composed so that electromotive force of the plating pot is controlled to 75 to 80 mV, and temperature of the plating pot is maintained to 440 to 455 deg.C, wherein 0.115 to 0.125 wt.% of Al is contained in the plating pot.