Topic:
Coupled Multielectrode
Sensors
for Real-Time Localized
Corrosion Monitoring
Abstract
Real-time monitoring plays an important
role in corrosion control and mitigation. The monitoring of localized
corrosion which accounts for the majority of the corrosion-induced failures,
however, has been a challenge to researchers, engineers and plant operators,
because it often takes place in small and isolated areas.
Multielectrode systems or wire beam
electrodes have been used successfully in the study of corrosion for
approximately fifteen years. Coupled multielectrode array (CMA) devices have
been used in the studies of spatially distributed electrochemical phenomena
and corrosion processes for nearly ten years. In a CMA device, multiple
electrodes that are electrically coupled behave as a one-piece metal in a
corrosive environment; corroding electrodes simulate the anodic sites, and
non-corroding or less corroding electrodes simulate the catholic sites of
the one-piece metal.
Recently, CMA devices have been used as
real-time sensors for in situ
and online monitoring of corrosion. Because the electrodes are spatially
distributed and have sensing surface areas close to the areas affected by
localized corrosion, the CMA sensor is sensitive for non-uniform, especially
localized corrosion measurements.
This presentation will provide an overview
of the principle and typical applications of the CMA sensor. Laboratory and
field test results obtained under a wide range of environments— including
liquids, humid air, soil, oil-water mixture, concrete, coatings,
salt-deposits or bio-deposits—will also be shared.
