This paper examines the effect of acid rain on sheltered and unsheltered areas of the patina of a quaternary bronze sculpture of King Louis XIV located in Versailles, France, as well as on artificially corroded G85 bronze coupons. The corrosion behaviour of the coupons was examined through wet-dry tests to simulate the stagnant and leaching rainfall conditions found on the sculpture. The results show that in sheltered conditions, the patina is a multi-layered system with an inner tin-enriched layer covered by copper and lead compounds. In runoff conditions, a tin-rich patina behaves as a thin porous layer allowing significant dissolution of the other alloying elements of the bronze. Therefore, properly aged surfaces, reflecting the complexity of real patinas, are needed for adequately testing corrosion inhibitors.
PREDICTING THE CORROSION BEHAVIOUR OF OUTDOOR BRONZES: ASSESSMENT OF ARTIFICIALLY EXPOSED AND REAL OUTDOOR SAMPLES / C. Chiavari; E. Bernardi; C. Martini; L. Morselli; F. Ospitali; L. Robbiola; A. Texier. - ELETTRONICO. - (2010), pp. 160-166. (Intervento presentato al convegno Triennial Meeting of the ICOM-CC Metal Working Group tenutosi a Charleston, South carolina, USA nel 11-15/10/2010).
PREDICTING THE CORROSION BEHAVIOUR OF OUTDOOR BRONZES: ASSESSMENT OF ARTIFICIALLY EXPOSED AND REAL OUTDOOR SAMPLES
CHIAVARI, CRISTINA;BERNARDI, ELENA;MARTINI, CARLA;MORSELLI, LUCIANO;OSPITALI, FRANCESCA;
2010
Abstract
This paper examines the effect of acid rain on sheltered and unsheltered areas of the patina of a quaternary bronze sculpture of King Louis XIV located in Versailles, France, as well as on artificially corroded G85 bronze coupons. The corrosion behaviour of the coupons was examined through wet-dry tests to simulate the stagnant and leaching rainfall conditions found on the sculpture. The results show that in sheltered conditions, the patina is a multi-layered system with an inner tin-enriched layer covered by copper and lead compounds. In runoff conditions, a tin-rich patina behaves as a thin porous layer allowing significant dissolution of the other alloying elements of the bronze. Therefore, properly aged surfaces, reflecting the complexity of real patinas, are needed for adequately testing corrosion inhibitors.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
