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

ABSTRACT

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.

KEYWORDS:

• Atmospheric corrosivity
• corrosion
• copper
• grey cast iron
• zinc

Acknowledgements

The authors would like to thank Professor Lídia Gil Catarino of the University of Coimbra for the guidance and support given regarding the use and interpretation of the spectrophotometric results. The authors would also like to thank Professor José M. Castanheira of the University of Aveiro for authorising the use of space for the rack and for providing data on meteorological variables observed in the meteorological station of the University of Aveiro. Finally, the authors would like to thank the Geophysics Institute of Coimbra for providing the space to perform this work, specifically Eng. Paulo Ribeiro for the support given to this project and for providing the required data from the Geophysics Institute’s meteorological station.

Disclosure statement

No potential conflict of interest was reported by the authors.

ORCID

A. M. Ferro Rocha http://orcid.org/0000-0001-9808-1387

Additional information

Funding

This work was supported by the Fundação para a Ciência e aTecnologia (FCT) in the framework of the research project ‘TRAPHIC – Traffic-related air pollution impacts on historic city centres: an integrated approach’, reference P2020-PTDC/ECM-URB/3329/2014.