Setup of galvanic sensors for the monitoring of gilded bronzes.
Traditional electrochemical techniques, such as linear polarization resistance (Rp), and electrochemical impedance spectroscopy (EIS), cannot be applied to gilded bronzes, as it may not be possible to interpret the results obtained due to the bimetallic nature of the studied material. The measurement of the macrocouple current generated by the gold/bronze galvanic couple can be used as an indicator of degradation processes. Nevertheless, this measurement cannot be performed directly on the original artifacts due to the systematic presence of short-circuits between the two metals. In the present work the use of galvanic sensors is proposed as a possible solution for the monitoring of gilded bronze artefacts. The sensors have been designed to simulate real gilded bronze surfaces in terms of composition and stratigraphy and have proved to be a reliable diagnostic tool for the in situ monitoring of the rates of deterioration of gilded bronze surfaces and to test new conservation treatments. Their set-up and application is reported and their performances discussed.
Department of Chemistry, Materials and Chemical Engineering "Giulio Natta", Politecnico di Milano, Via Mancinelli 7, 20131 Milano, Italy. sara.goidanich@polimi.it.
Sara
S
Goidanich
Department of Chemistry, Materials and Chemical Engineering "Giulio Natta", Politecnico di Milano, Via Mancinelli 7, 20131 Milano, Italy. davide.gulotta@polimi.it.
Davide
D
Gulotta
Haute-Ecole Arc Conservation-Restauration, Espace de l'Europe 11, 2000 Neuchâtel, Switzerland. laura.brambilla@he-arc.ch.
Laura
L
Brambilla
Chemistry Department, University of Fribourg, Chemin du Musée 9, CH-1700 Fribourg, Switzerland. ruben.beltrami@unifr.ch.
Ruben
R
Beltrami
Department of Chemistry, University of Milan, Via Golgi 19, 20133 Milan, Italy. paola.fermo@unimi.it.
Paola
P
Fermo
Department of Chemistry, Materials and Chemical Engineering "Giulio Natta", Politecnico di Milano, Via Mancinelli 7, 20131 Milano, Italy. lucia.toniolo@polimi.it.
Lucia
L
Toniolo