Atmospheric corrosion in two different urban environments in Portugal: results of one-year exposure

An atmospheric corrosion campaign was carried out to update the information on the environmental corrosivity in Portugal, available from earlier MICAT and ICP-Materials projects. This communication summarises the initial atmospheric corrosion of copper, zinc and grey cast iron in the cities of Coimbra and Aveiro. The new data was produced in the scope of the project TRAPHIC, which aimed at evaluating the effects of air pollution on materials in the city of Coimbra. Samples of the three metals were exposed in three different locations and the surface modifications were monitored over time together with the local environmental conditions. Chromatic alterations in copper and zinc were analysed and corrosion products were characterised using SEM/EDS. First-year corrosion rates were measured for the three locations to complement the national corrosivity map. Results indicate the reduction of acidic pollution and decreasing of corrosion rates over the past 30 years in Portugal.