| 摘要 |
Disclosed herein are a spangle-free, hot-dip galvanized steel sheet, and a method and device for manufacturing the same. The hot-dip galvanized steel sheet is characterized in that a solidified zinc crystal of hot-dip galvanized layer has an average crystalline texture particle diameter of 10 to 88, and there is no solidification traces of dendrites upon observing under a microscope at a magnification of 100X. The hot-dip galvanized steel sheet comprises dipping a steel sheet in a bath of a zinc-coating solution containing 0.13 to 0.3% by weight of aluminum; air-wiping the steel sheet to remove an excess of the coating solution; spraying water or an aqueous solution on the air-wiped steel sheet, using a steel sheet temperature in the range of a hot-dip galvanization temperature to 419~C as a spray initiation temperature and using a steel sheet temperature in the range of 417~C to 415~C as a spray completion temperature; passing sprayed liquid droplets of water or aqueous solution through a mesh-like high- voltage charged electrode which is electrically charged with a high voltage of -1 to -50 kV; and allowing the electrode-passed liquid droplets to be bound to the surface of the steel sheet and thereby being served as solidification nuclei of molten zinc. The hot-dip galvanized steel sheet of the present invention exhibits superior corrosion resistance, blackening resistance, oil stain resistance, surface friction coefficient and surface appearance, and can be used for a variety of materials such as inner and outer plates of car body, household electric appliances and construction materials and steel sheet for painting. |
