Corrosion Protection Improving Retreatment Method for Metal Surfaces and Conversion Coatings.

A study of the mechanism of corrosion of chromized zinc coatings has revealed that the currently available commercial chromizing treatments are capable of improvement. It is recommended that certain organic polymers, such as those with an acrylate, acrylate/styrene and alkyd resin base, be employed after the chromizing treatment to seal the chromate coating, so that dewatering is largely prevented. The possibility of obtaining excellent corrosion resistance on galvanized and ungalvanized surfaces without prior chromizing by employing the above-mentioned organic polymers simultaneously with chromium (VI) and phosphate compounds is also noted.