The use of the electrochemical micro-cell for the investigation of corrosion phenomena

Electrochemical micro-cell systems based on the use of glass micro-capillaries enable to perform standard electrochemical measurements on areas with dimension in the micro- or submicrometer range. The base principle is the miniaturization of the working electrode, which is obtained using a micro-capillary to position the electrolyte on the sample surface. This technique has been extensively employed for the investigation of localized corrosion in passive surfaces like steels and aluminium alloys.This paper presents examples of the study of localized corrosion and its inhibition in aluminium alloys by means of the electrochemical micro-cell. These are discussed trying to highlight the major advantages and the critical aspects related to the use of the technique. Moreover, the combined use of the electrochemical micro-cell with other electrochemical and surface analysis techniques highlights that the micro-cell technique is a very powerful method for the investigation of corrosion phenomena.