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Potentiometric Probes
Published in Allen J. Bard, Michael V. Mirkin, Scanning Electrochemical Microscopy, 2022
Guy Denuault, Geza Nagy, Klara Tóth
The earliest forms of SECM experiments were carried out in the potentiometric mode. Evans128 reported how he used a traveling reference electrode to map equipotential surfaces in solution and calculate corrosion rates on a water pipeline. Isaacs129,130 revived the idea in 1972 and coined the acronym SRET for scanning reference electrode technique. Instruments used to be home made, often with rudimentary traveling devices such as the arm of an X-Y recorder129,131 and the spatial resolution was at best submillimeter. A computer-controlled instrument was commercially produced by Uniscan Instruments with a spatial resolution around 20 μm.132 The SRET has now been superseded by the scanning vibrating electrode technique,133 known as SVET, which achieves higher spatial resolution134 and improved sensitivity. SVET workstations are now commercially available from BioLogic and AMETEK Scientific Instruments.
Electrochemical techniques for studying tribocorrosion processes in situ
Published in J.-P. Celis, P. Ponthiaux, Testing tribocorrosion of passivating materials supporting research and industrial innovation: Handbook, 2017
Vincent Vignal, François Wenger, Bernard Normand
– Scanning techniques, where the immersed metal surface is scanned with a microprobe to measure the potential in a static mode (Scanning Reference Electrode Technique SRET) or the current in a vibrating mode (Scanning Vibrating Electrode Technique SVET). A conventional SRET has been modified to provide a novel method for characterizing the real-time localized tribocorrosion behavior of uncoated and PVD C/Cr coated samples during rubbing [55]. The influences of various testing conditions involving contact load and test environments have been demonstrated, and have been found to affect some electrochemical parameters (local anodic current, number of active anodic areas, sample (repassivation) recovery time, free corrosion potential) and mechanical parameters (amount of wear, wear coefficient and wear morphology). More recently, the Scanning electrochemical Microscope (SECM, Figure 4.16) allows the mapping of species distribution around an active site.
Carbon Nanoallotropes-Based Anticorrosive Coatings
Published in Hatem M.A. Amin, Ahmed Galal, Corrosion Protection of Metals and Alloys Using Graphene and Biopolymer Based Nanocomposites, 2021
Khaled M. Amin, Hatem M.A. Amin
To investigate the presence of localized corrosion of steel, the study applied the Scanning Vibrating Electrode Technique (SVET) (Fig. 3). As the steel electrode in pure HCl solution was exposed to severe corrosion, it showed the highest positive current. On the other hand, a significant decrease in the current was observed in case of imidazole and FCDs solutions and the highest decrease in current was observed for FCDs. This observation confirms that the corrosion inhibition is induced by the FCDs. Moreover, as shown in Fig. 3, current density decreased with the increase in inhibitor concentration and immersion time.
Comparing the corrosion behaviour of AA2050 and AA7050 aluminium alloys by scanning vibrating electrode and scanning ion-selective electrode techniques
Published in Corrosion Engineering, Science and Technology, 2022
Bárbara Victoria Gonçalves De Viveiros, Uyime Donatus, Maicon Cavalieri De Alencar, Larissa Oliveira Berbel, Isolda Costa
In the present study, the corrosion resistance of the AA2050-T84 and AA7050-T7451 alloys and their galvanic interactions were investigated by scanning vibrating electrode technique (SVET) and scanning ion-selective electrode technique (SIET) alongside microscopic techniques to examine the extent and morphologies of corrosion in these two alloys. SVET and SIET are very useful techniques to evaluate galvanic activities [21,22] and localised corrosion resistance [23,24].