| 摘要 |
PURPOSE: A method for manufacturing a zero spangled hot dipped galvanized iron with superior surface quality is provided which has superior plating cohesion over a period of time lapsed even on a minimized spangle, and has neither flow marks nor pitting defects due to manufacturing of the minimized spangle. CONSTITUTION: The method for manufacturing a hot dipped galvanized hot rolled strip with superior surface quality comprises the steps of plating the pickled hot rolled strip by dipping a pickled hot rolled strip into a plating pot comprising 0.18 to 0.25 wt.% of Al, 0.01 wt.% or less of Pb, 0.05 to 0.075 wt.% of Sb and a balance of Zn and inevitable impurities; manufacturing a minimized spangle by spraying an ammonium hydrogenphosphate solution onto the hot rolled strip dipped into the plating pot just before the hot zinc is solidified; and skin passing the surface of the plating layer to a reduction force of 150 tons or more using a shot blast texturing dull roll.
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