Inhibition of cut edge corrosion of coil-coated architectural cladding

This study has investigated the solubility of inhibiting pigments and also the leaching behaviour of corrosion inhibitors from a polyester binder in an acid rain solution. This study has relevance to the control of cut-edge corrosion by inhibitor pigments, which are incorporated into the primer coatings of coil-coated architectural cladding. The concentrations of leachate solutions in tubes glued to the top surface of primer-coated galvanised steel specimens were measured using inductively coupled plasma emission spectroscopy (ICPES) for a range of commercial inhibitors. In addition, the saturated solubility was measured using ICPES. It was found that the leaching rate, rather than the saturated solubility, controls the amount of inhibitor which is available for corrosion control at cut edges and in a coating defect area. These results are compared to impedance testing of polyester-coated galvanised steel specimens coated with the same primers. # 1999 Elsevier Science S.A. All rights reserved.