An electrochemical and mechanical approach to the corrosion
resistance of cathodic electrocoatings under combined cyclic and DC
polarization conditions

Sepehr Lajevardi Esfahani

article info

Article history
Received 6 August 2013
Received in revised form 13 February 2014
Accepted 29 March 2014

Keywords: Cyclic test, EIS, Polarization, Electrocoated films, Corrosion

abstracts

A modified AC/DC/AC test has been introduced. It consists of a combination of EIS test, cathodic polarizations, wet and dry cycles. This test method was applied to cathodically electrocoated mild steel substrates baked at different conditions. This study aims at characterizing protective behavior of under-, normaland over-baked electrocoatings under cyclic corrosion conditions. It was found that the resistive failure is the dominant failure mechanism of all the coatings in this test. It was also found that a low crosslink density coating withstands the mechanical stresses due to dry–wet cycles better than a higher crosslink density one.