A new insight into the rate determining step of cathodic delamination

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.

Automated summary

Cathodic delamination is one of the most important mechanisms in organic coating degradation. While significant progress has been made towards understanding the fundamentals of delamination, the underlying key parameters are still not fully comprehended. In this study, a new hypothesis is proposed that cation insertion into the intact interface determines the rate of delamination, based on the analysis using a combined Scanning Kelvin Probe/potentiostat set-up and in-depth delamination rate analysis.