Evaluation of Corrosion Characteristics of Zn-Al and Zn Arc Thermal Spray Coatings Using Atmospheric Exposure Tests

Abstract

In this study, atmospheric exposure tests were conducted using Zn-Al arc thermal spray coatings, Zn arc thermal spray coatings, and hot-dip Zn coatings at two locations: the Kibana Campus and the Nobeoka Field of the University of Miyazaki. The corrosion characteristics of each coating were compared by surface observation, film thickness measurement, XRD and SEM/EDX analysis, from the viewpoint of differences in composition. As a result, no significant corrosion was observed in the Zn-Al arc thermal spray specimens even after two years of atmospheric exposure test, while corrosion product deposition was observed in the Zn arc thermal spray and hot-dip Zn specimens.