CHROMIUM HYDROXIDE PLATING SOLUTION AND METHOD FOR FORMING CHROMIUM HYDROXIDE FILM HAVING LOW CONTACT RESISTANCE DURING SEAM WELDING USING THE SAME

摘要

PURPOSE: A chromium hydroxide plating solution and a method for forming chromium hydroxide film having a low contact resistance during seam welding using the same are provided to form a chromium hydroxide plating layer having superior seam weldability by welding after forming a chromium hydroxide layer using an electrolyte to which an appropriate concentration of ethanol is added, thereby not increasing welding resistance. CONSTITUTION: The chromium hydroxide plating solution comprises 40 to 80 g of chromic acid, 0.05 to 0.15 g of sulfuric acid, 0.5 to 2.0 g of hydrofluorosilicic acid, 5 to 15 g of ethanol and a balance of water. The method comprises the processes of preparing a base steel sheet by forming a tin plating layer on the pore area of the metallic chromium layer after forming a metallic chromium layer on the surface of which pores are formed on a steel sheet; and immersing the base steel sheet into the chromium hydroxide plating solution, and anode electrolyzing the base steel sheet immersed into the chromium hydroxide plating solution so that a thickness of the chromium hydroxide formed on the tin plating layer is comparatively thinly formed than a thickness of the chromium hydroxide formed on the metallic chromium layer, wherein a current density during the anode electrolyzing is 10 to 30 A/m2, and a contact resistance of a chromium hydroxide plating layer manufactured by the method is 5x 10¬-4 Ω or less.