| 摘要 |
PURPOSE:To obtain a Cr plating soln. enabling deposition to a large thickness and forming plating having satisfactory corrosion resistance by incorporating hexavalent and tervalent Cr ions, an org. acid and iodic acid or iodate. CONSTITUTION:An aq. soln. contg. about 100-1,000g/l chromic acid, about 50-1,000g/l org. acid and about 2-10g/l iodic acid or iodate is adjusted to about 1.5-3.0pH with sulfuric acid or an aq. ammonia soln. to obtain a Cr plating soln. The reduction of Cr in the plating soln. is accelerated by both the org. acid and iodic acid, rapid plating proceeds and thick plating having satisfactory corrosion resistance is obtd. The hardness of the resulting plating is increased by heat treatment. |
