Q. The nickel deposit we are obtaining from our nickel sulfamate plating bath is noticeably brighter than the results we were getting six months ago. We do not add any brighteners to the bath. What is going on?—S.B.
A. You are forming a brightening agent in the sulfamate nickel solution. The sulfamate in the plating bath is gradually being oxidized to azodisulfonate. This usually occurs when you have polarized or inert anodes. The best way to handle the problem is to treat the bath with peroxide and carbon.