A new insight into the rate determining step of cathodic delamination

Abstract

One of the most important mechanisms of organic coating degradation is cathodic delamination. Although a significant progress towards the fundamentals of delamination was achieved in the recent decades, the underlying key parameters are not fully understood. It is believed that either cation migration along the delaminated interface or oxygen reduction at the interface are rate determining. However, as will be shown here this is not the case. A new hypothesis, which is cation insertion into the intact interface as the rate determining step in delamination, is proposed using a combined Scanning Kelvin Probe/potentiostat set-up and an in-depth delamination rate analysis.

Topics & Concepts