Several common-use artifacts (coins, faience, cult objects, etc.) coming from two excavations sites near Rio de Janeiro, two sugar farms Historico do Rochedo and Cruzeiro, have been the subject of this investigation, which aimed to integrate physico-chemical characterizations with the identification of degradation mechanisms, and the proposal of innovative conservation methods, such as PECVD deposition of SiO2-like films for protection of metallic artifacts. For the microchemical, micromorphological and microstructural analysis, optical microscopy-OM, X-ray diffraction XRD, X-ray fluorescence-XRF, and scanning electron microscopy equipped with electron microprobe-SEM + EDS have been employed. A cleaning step followed by a consolidation step has been carried out on glassy artefacts, while on metallic artefacts the mechanical cleaning has been followed by a stabilization treatment when necessary. For long-term protection the deposition by PECVD of SiO 2-like films has been performed on a series of copper-based alloys in a home made reactor fed with an tetraethoxysilane-oxygenargon mixture. The coatings show a good barrier effect against the diffusion of water and oxygen from the environment to the metal surface, that increases with increasing the oxygen to monomer ratio in the feeding gas mixture and the input power density. Moreover, the coating adhesion increases if the deposition process is performed after a hydrogen plasma treatment.

Integrated approach to the characterization and conservation of artefacts of the Brazilian colonial period / Angelini, EMMA PAOLA MARIA VIRGINIA; Grassini, Sabrina; Solorzano, G; DO NASCIMENTO CAMPOS, G; DE CARO, Tilde. - In: APPLIED PHYSICS. A, MATERIALS SCIENCE & PROCESSING. - ISSN 0947-8396. - STAMPA. - 83:4(2006), pp. 485-491. [10.1007/s00339-006-3544-x]

Integrated approach to the characterization and conservation of artefacts of the Brazilian colonial period

ANGELINI, EMMA PAOLA MARIA VIRGINIA;GRASSINI, Sabrina;DE CARO, TILDE
2006

Abstract

Several common-use artifacts (coins, faience, cult objects, etc.) coming from two excavations sites near Rio de Janeiro, two sugar farms Historico do Rochedo and Cruzeiro, have been the subject of this investigation, which aimed to integrate physico-chemical characterizations with the identification of degradation mechanisms, and the proposal of innovative conservation methods, such as PECVD deposition of SiO2-like films for protection of metallic artifacts. For the microchemical, micromorphological and microstructural analysis, optical microscopy-OM, X-ray diffraction XRD, X-ray fluorescence-XRF, and scanning electron microscopy equipped with electron microprobe-SEM + EDS have been employed. A cleaning step followed by a consolidation step has been carried out on glassy artefacts, while on metallic artefacts the mechanical cleaning has been followed by a stabilization treatment when necessary. For long-term protection the deposition by PECVD of SiO 2-like films has been performed on a series of copper-based alloys in a home made reactor fed with an tetraethoxysilane-oxygenargon mixture. The coatings show a good barrier effect against the diffusion of water and oxygen from the environment to the metal surface, that increases with increasing the oxygen to monomer ratio in the feeding gas mixture and the input power density. Moreover, the coating adhesion increases if the deposition process is performed after a hydrogen plasma treatment.
File in questo prodotto:
Non ci sono file associati a questo prodotto.
Pubblicazioni consigliate

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11583/1524866
 Attenzione

Attenzione! I dati visualizzati non sono stati sottoposti a validazione da parte dell'ateneo