Field Experiment to Partition the effects of Dry and Wet Deposition on Metallic Materials

摘要

At a material exposure site located at the Research Triangle Park, NC, the Environmental Protection Agency began in 1982 a study to partition the effects of dry and wet deposition on galvanized and weathering steel panels. At the site, air quality and meteorological parameters are continuously measured and reported as hourly averages. The concentration and chemistry of particles and the amount of rainfall and chemistry are also recorded. In this study a mobile device covers a set of panels only during each rain event. Another set of panels is exposed uncovered at the site. The panels are exposed and cleaned according to standard ASTM procedures. After two years of exposure the weight-loss of the galvanized steel for the uncovered exposure was nearly twice the weight-loss recorded for the covered condition.