Localized electrochemical techniques: Theory and practical examples in corrosion studies

This paper aims at giving an idea of the contributions to the study of corrosion phenomena ensured by the practice of localized electrochemical techniques. For many corrosion phenomena high resolution is required. This is due to the fact that a huge amount of relevant information about electrochemical processes can be examined at a microscale.The present work is focused both on theoretical and practical aspects of these modern localized electrochemical techniques. In particular Scanning Kelvin Probe (SKP) and Scanning Vibrating Electrode Technique (SVET) will be discussed in detail. Concerning theoretical aspects, this paper summarizes in some fundamental equations the main operating principles behind the two different techniques. The basics of the two equipments are explained in simple terms with the aid of some pictures. Experimental data are also reported, in order to better understand the working principles of these devices and their potential. The novelty of the data obtained with these tools will be highlighted by the discussion of the theoretical principles and the explanation of several examples.