Atmospheric corrosion of Cu-Si-Mn bronze for contemporary art under simulated runoff and continuous immersion conditions. (15th August 2022)

• Record Type: Journal Article
• Authors: Chiavari, Cristina; Martini, Carla; Balbo, Andrea; Monticelli, Cecilia; Velino, Cecilia; Masi, Giulia; Bernardi, Elena
• Is Part Of: Corrosion science. Volume 205(2022)
• Publication Date: 2022-08-15
• Subjects: Copper (A) -- Alloy (A) -- EIS (B) -- IR spectroscopy (B) -- SEM (B) -- Atmospheric corrosion (C); Corrosion and anti-corrosives -- Periodicals; 620.11223
• DOI: 10.1016/j.corsci.2022.110442
• Languages: English
• ISSNs: 0010-938X

Abstract

Abstract: Silicon bronze is widely used for monuments: corrosion of Cu-3Si-1Mn was studied with respect to Cu-5Sn-5Zn-5Pb during ageing tests (runoff/full immersion) in acid rain. Surface characterisation (FEG-SEM/EDS elaborated through PCA, TEM, Raman, FTIR, profilometry), metal release and EIS measurements were performed. Under runoff conditions, where mechanical action plays a role, the alloys showed comparable corrosion resistance. In full immersion the corrosion rate of Cu-3Si-1Mn was slightly higher than that of Cu-5Sn-5Zn-5Pb, due to the different nature of the corrosion products. Results showed that, compared to Sn oxide/hydroxide, Si tends to form less protective amorphous products, detaching from the surface. Highlights: Need of less toxic, Pb-free copper-based alloys for industry and art. Study of mechanisms of atmospheric corrosion of an as-cast Si-Mn bronze. Simulation of unsheltered outdoor conditions through runoff test. Surface, electrochemical and metal release analyses; statistical (PCA) elaboration. Corrosion influenced by microstructure and different from traditional bronze.