J.CAC VOLUME 42 (2017)

Practical Electrochemistry for Conservators and Conservation Scientists: Part I – The Basics of Potential Measurement

Lyndsie Selwyn, W. Ross McKinnon

Electrochemical techniques are used in conservation to identify metals or corrosion products, or to monitor or treat metal objects. Although there are many published reports on these techniques, it is difficult to find practical information on how to get started to use them. This paper provides some of this information for one important application of these techniques, namely measurement of corrosion potential (the potential of an object immersed in a liquid electrolyte with respect to a reference electrode). Topics covered include electrochemical cells, multimeters, electrical connection to objects, electrolytes and, especially, reference electrodes – common types of reference electrodes, how to use, protect and maintain them, and how to troubleshoot problems. Examples are given of measuring corrosion potential and using Pourbaix diagrams.

Download: JCAC42 Selwyn & McKinnon I