Abstract
For many industrial applications, corrosion is a life-limiting phenomenon and therefore requires careful consideration and rigorous experimental testing before structural materials can be reliably deployed, particularly in harsh chemical environments. The traditional approach to measuring corrosion requires exposing many samples to the intended environment and then extracting them individually at discrete intervals for postexposure characterization. This approach does not provide a high degree of temporal resolution, nor does it provide any real-time information regarding dynamic changes in corrosion rates. Developing an online corrosion monitor capable of surviving harsh chemical environments could provide valuable information regarding the structural health of components and changing process conditions that could accelerate corrosion. To this end, a corrosion sensor was developed based on a pressure-driven Fabry-Pérot cavity (FPC). This sensor uses a pressure control system to internally pressurize the FPC formed between the sensor's housing and a metal-embedded singlemode optical fiber. Simultaneous measurement of the change in FPC length using low-coherence interferometry and the applied pressure enables the calculation of the relative changes in the sensor's diaphragm thickness due to corrosion on its outer surface. Measurements were made in situ while actively corroding the sensor and were validated against surveillance specimens that were corroded simultaneously. The uncertainties in the measured corrosion were analyzed using error propagation of the uncertainties in the measured pressures and displacements and were found to be <1% of the initial diaphragm thickness.
| Original language | English |
|---|---|
| Article number | 9454553 |
| Journal | IEEE Transactions on Instrumentation and Measurement |
| Volume | 70 |
| DOIs | |
| State | Published - 2021 |
Funding
Manuscript received March 3, 2021; revised April 26, 2021; accepted May 31, 2021. Date of publication June 14, 2021; date of current version June 30, 2021. This work was supported by UT-Battelle, LLC, with the U.S. Department of Energy (DOE) under Contract DE-AC05-00OR22725. The U.S. Government retains and the publisher, by accepting the article for publication, acknowledges that the U.S. Government retains a nonexclusive, paid-up, irrevocable, worldwide license to publish or reproduce the published form of this manuscript, or allow others to do so, for U.S. Government purposes. DOE will provide public access to these results of federally sponsored research in accordance with the DOE Public Access Plan (http://energy.gov/downloads/doe-public-access-plan). The Associate Editor coordinating the review process was Ada Fort. (Corresponding author: Daniel C. Sweeney.) The authors are with the Fusion and Fission Energy and Science Directorate, Oak Ridge National Laboratory, Oak Ridge, TN 37830 USA (e-mail: [email protected]). Digital Object Identifier 10.1109/TIM.2021.3089231
Keywords
- Corrosion monitoring
- low-coherence interferometry
- optical fiber sensor
- pressure control system