METHOD FOR MANUFACTURING GALVANNEALED STEEL SHEET

摘要

PURPOSE: A method for manufacturing a galvannealed steel sheet for an automobile panel is provided to prevent surface defects such as groove mark by injecting a trace amount of zinc powder on the surface of a galvanized iron that is under Zn-Fe heat treatment. CONSTITUTION: The method is characterized in that zinc powder with a particle size of 10μm or less is sprayed onto the surface of a galvannealed iron at 1/3-1/2 point of whole length of soaking zone. Wherein, the spray pressure of zinc powder is 0.1-0.3kg/cm¬2 and the spray amount of zinc powder is 1-3g/m¬2.