Environmental Integrity of Coating/Metal Interface
Annual progress rept. 1 Feb 1988-31 Jan 1989
ROCKWELL INTERNATIONAL CORP THOUSAND OAKS CA SCIENCE CENTER
Pagination or Media Count:
It is the objective of this project to establish the molecular details of the corrosion-induced loss of adhesion of organic films from steel. Scanning acoustic microscopy SAM has allowed observation of the microscopic details of the attack of cathodic corrosion products on a model organic coating on steel. Attack of the polymer by the alkaline corrosion products occurs at numerous localized regions resulting in the mechanical degradation of the coatingmetal interface. Acoustic microscopy has also provided a rapid determination of the kinetics of the disbonding process. The disbond distance away from a cathodically polarized scribe increases with the square root of time. The corresponding rate parameter Kd increases with increasing potential for applied potentials below -750 mV vs AgAgCl.
- Coatings, Colorants and Finishes