Real-time Corrosion Research Articles

In situ fluorescence imaging of localized corrosion with a pH-sensitive imaging fiber.

A fiber-optic pH-imaging sensor array capable of both visualizing remote corrosion sites and measuring local chemical concentrations at these sites was applied to realtime corrosion monitoring. The imaging fiber's distal face, containing an immobilized pH-sensitive fluorescent dye, was brought into contact with metal surfaces submerged in aqueous buffers and fluorescence images were acquired as a function of time. Heterogeneous fluorescence signals were observed due to both pH increases at cathodic surface sites and pH decreases at anodic surface sites. These fluorescence signals showed both localization and rates of corrosion activity. Three corrosion processes were investigated, galvanic corrosion at a copper/aluminum interface and crevice corrosion and pitting at a stainless steel surface. The spatial resolution of the technique was limited by proton/hydroxide diffusion and the diameter of the individually clad optical fibers comprising the imaging bundle.

Bulk Acoustic Wave Technique as a Real-Time Corrosion Probe in Low-Conductivity Solution: In-Situ Corrosion Behavior of Copper in Acetic Acid

Abstract The possibility of using the bulk acoustic wave (BAW) technique to study metal corrosion in low-conductivity organic solvents was demonstrated in relation to copper corrosion in acetic aci...

Electrochemical Emission Spectroscopy for Monitoring Uniform and Localized Corrosion

Abstract A modified electrochemical noise (EN) technique (electrochemical emission spectroscopy [EES]) was developed for nondestructive, real-time corrosion rate measurements. Unlike conventional c...

Real-time performance monitoring of fouling and under-deposit corrosion in cooling water systems

To better understand and simulate the operational impact of fouled surfaces in cooling water applications, a number of site installations have been equipped with on-line instrumentation to evaluate variability of scaling and fouling behaviour during normal plant operation. However, a major drawback of the conventional fouling monitors has been their inability to indicate real-time corrosion activity beneath surface deposits; rather, it has been necessary to destructively evaluate test heat exchanger tubes and/or rely upon use of corrosion coupons and probes under non-heat flux conditions. A recent initiative has been the development of a combined corrosion and fouling instrument. This unit is capable of providing a real-time indication of corrosion activity under heat transfer conditions at the tube-wall surface. An overview of the results obtained from recent trials is presented and discussed.