Method of producing corrosion- resistance steel sheet coated with zirconium and silane coupling agent

摘要

PURPOSE: Provided is a method of producing a phosphate treated steel sheet with superior corrosion resistance and wettability by performing zirconium coating on the surface of phosphate treated steel sheet, along with applying silane coupling agent. The present invention is environmental-friendly method because chrome sealing treatment that is generally employed to avoid pit corrosion is not required. CONSTITUTION: In a production of phosphate treated steel sheet by using cold strip and/or galvanized steel, the present invention comprises the steps of dipping a phosphate treated steel sheet in a zirconium solution containing zirconium 0.003-0.01 M for 2-7 seconds to deposit zirconium film on the phosphate treated steel sheet; after deposition of zirconium on the phosphate treated steel sheet, drying it in the temperature of 120 to 200C followed by air-cooling or water-cooling; after coating the phosphate treated steel sheet with zirconium, dipping it in a silane solution containing silane compound 0.02-0.2 M for 2-7 seconds; curing it in the temperature range of 140-200C followed by air-cooling or water-cooling.