Investigation on the De-adhesion Resistance of Bituminous Coatings

Authors

1 Polymer Engineering Department, Amirkabir University of Technology

2 Department of Polymer Engineering and Color Technology, Amirkabir University of Technology

Abstract

Two types of bituminous coating, bitumen and coal tar pitch, were investigated using cathodic delamination and adhesion measurements. The bituminous coatings were applied on shot blasted steel with 100 µm thickness and then were subjected to cathodic delamination and wet adhesion tests during immersion in %3.5 NaCl w/w solution. The wet adhesion test results showed good agreement with cathodic delamination resistance. It could be indicate that the mechanism of cation diffusion to the interface in cathodic delamination process is similar to immersion condition without applied voltage. The mechanism of cation diffusion for bitumen based coating was through the intact coating and for coal tar pitch based coating was through defects in coating. The results showed that the cathodic delamination process is a criterion for estimating of the wet adhesion failure during immersion time.

Keywords