Corrosion Resistance of Bright Nickel Coatings in the Vapor of Acetic Acid

We study the corrosion behavior of bright nickel coatings in the vapor of concentrated acetic acid. Deposits with a sulfur content of 0.25 wt.% are obtained from electrolytes intended for bright nickel plating with an admixture of saccharin (5 g/dm 3 ). It is shown that their potentials vary within the range [(–0.02)–(– 0.01) V]. Moreover, it is demonstrated that, in the course of holding of these nickel deposits in the vapor of acetic acid, the amount of sulfur on the metal surface gradually increases and reaches 3.32 wt.%. It is established that the sulfur content of the film of black-color corrosion products formed after holding in the vapor for 24 h is close to 22 at.% and corresponds to nickel sulfide.