Observations on chromate conversion coatings from a sol-gel perspective

Chromate conversion coatings (CCCs) have been applied to aluminum substrates for many years to improve corrosion resistance and paint adhesion In recent years the so-called sor-gel chemistry based coating systems have been examined as possible replacements for CCCs on aluminum. A mechanism is proposed for the formation of CCC on aluminum that is consistent with sol-gel chemistry principles. The conclusions illustrate important considerations for developing non-CCCs for aluminum. (C) 2001 Published by Elsevier Science B.V.