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Effects of cleaning procedures on the long-term corrosion behavior of bronze artifacts of the cultural heritage in outdoor environment

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The cleaning of metallic artworks is a crucial step for their preservation. Cleaning operations generally aim at removing deposits and corrosion layers, and all the non-stable and potentially reactive phases formed as a consequence of the interaction of the metal with the environment. Thus, all secondary-formed compounds and layers that can undermine the overall preservation of the artwork, both from the esthetic and the corrosion point of view, should be removed. On the other hand, superficial stable patinas contributing to the artistic and historic value of the objects and that may provide protection to the metallic surface should be preserved. The optimal cleaning procedure should be able to promote a long-term improvement of the corrosion resistance of the surfaces. Therefore, the long-term monitoring of the corrosion behavior of the cleaned surfaces with electrochemical techniques could provide valuable information for the selection of the optimal methodology. In this work, five cleaning procedures have been applied to five bronze sculptures. The cleaned surfaces have been characterized following a multi-analytical and non-invasive approach, and the long-term evolution of their corrosion behavior has been monitored by means of on-site non-invasive linear polarization resistance (LPR) and electrochemical impedance spectroscopy (EIS) measurements for more than 2 years.

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The authors are grateful to Fonderia Artistica Battaglia for the fundamental support and collaboration to this research, and to Maria Agnese Zappa for her precious contribution to the experimental activity.

Author information

All authors contributed to the study conception and design.

Material preparation was performed by Bruna Mariani.

Data collection and analysis were performed by Chiara Petiti, Sara Goidanich, and Davide Gulotta.

The draft of the manuscript was written by Chiara Petiti. All authors commented on previous versions and read and approved the final manuscript.

Lucia Toniolo and Sara Goidanich supervised the whole research and writing activity.

Correspondence to Chiara Petiti.

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Petiti, C., Toniolo, L., Gulotta, D. et al. Effects of cleaning procedures on the long-term corrosion behavior of bronze artifacts of the cultural heritage in outdoor environment. Environ Sci Pollut Res (2020). https://doi.org/10.1007/s11356-020-07814-4

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  • Long-term monitoring
  • Cleaning
  • Outdoor bronze
  • Cultural heritage
  • Atmospheric corrosion
  • Electrochemical techniques