> ... research into sacrificial anodes and how useful they can be for outdoor > sculptures ...
The reason that the literature you found is geared towards underwater applications is because sacrificial anodes only work under water (or some other fluid which conducts electricity, known as an electrolyte). Corrosion is an electrochemical process, which means current flows. If you connect two different metals together, electrons will want to flow from one metal to the other, where the metal losing electrons will corrode (the anode in the galvanic corrosion process). In the case of the sacrificial anode, it corrodes instead of the object you want to protect. But that can only happen if the electric circuit is complete. Electrons can't just flow one way without something flowing the other way, and that is only when both metals are in contact with each other in an electrolyte, i.e. under water. Then there is ionic flow through the electrolyte to keep the metals electrically neutral. In any case, there is an ethical issue with using sacrifical anodes. You have to somehow firmly attach the sacrificial anode to the object you are protecting to ensure good electrical contact. Dr. W. (Bill) Wei Senior Onderzoeker / Senior conservation scientist Rijkserfgoedlaboratorium / Cultural Heritage Laboratory Ministerie van Onderwijs, Cultuur en Wetenschap Rijksdienst voor het Cultureel Erfgoed Bezoek|Visit|Courier: Hobbemastraat 22 | NL-1071 ZC | Amsterdam Post|Mail: Postbus 1600 | NL-3800 BP | Amersfoort The Netherlands T +31 33 421 7183 M +31 6 5273 2101 b....@cultureelerfgoed.nl<mailto:b....@cultureelerfgoed.nl> www.cultureelerfgoed.nl<http://www.cultureelerfgoed.nl> ****** Unsubscribe by sending a message to consdistlist-le...@cool.conservation-us.org Searchable archives: http://cool.conservation-us.org/byform/mailing-lists/cdl/
