PRETREATMENT FOR ZINC AND ZINC ALLOY PRIOR TO CHROMATING

摘要

Drying into place a covering of an aqueous solution of nickel and/or cobalto us sulfate and/or phosphate sans on a zinc or zinc alloy surface improves at least one of the blackening resistance and corrosion resistance after subsequent chromating treat- ment and the corrosion resistance and paint adherence after subsequent chromating treatment and painting.