Manufactuing methods of galvannealed sheet steels with good anti-powdering

摘要

PURPOSE: A method for manufacturing galvannealed sheet steels with good anti-powdering is provided, in which by the addition of cerium in plating solution, the growth of gamma-phase, an intermetallic compound of zinc and iron, is restricted. CONSTITUTION: The method is characterized in that 0.005-0.02wt% of cerium is added in conventional plating solution of which aluminium concentration is 0.12-0.14wt% so that the growth of gamma-phase, an intermetallic compound of zinc and iron, is restricted thus securing excellent powdering resistance. The plating solution is coated on one surface of a steel sheet in an amount of 60g/m¬2 to 100g/m¬2.