SwRI: Sensors and Corrosion Monitoring, Coating Degradation Sensor (CDS), Corrosion Testing and Research

To protect engineered structures from corrosion and environmental attack, protective measures are taken with paint, temporary coatings corrosion preventative compounds (CPCs), tape coatings or appliqu? which form an insulating, inert and impervious protective layer on the alloy surface.

Degradation of these coatings through the adsorption of water, coating damage, defects, and weathering can lead to reduced protection, corrosion and ultimately loss of structural integrity. Monitoring the condition of the protective coating can provide information to trigger maintenance actions and prevent corrosion of the engineered structure.

Coating degradation sensor performance for aluminum alloys		Coating degradation sensor performance for carbon steel with and without coating defects

Key Features of the Coating Degradation Sensor

• U.S. Patent No. 6,911,828

• Detection of changes in coating performance such as water uptake and environmental degradation of the coating

• Sensitivity to coating defects such as thin spots and fisheyes

• Detection of mechanical damage

• Sensor can be embedded in the structure to detect changes in coating performance prior to onset of corrosion

• Field evaluation of protective coatings

Field Deployable Sensor Network

A field deployable sensor network capability has been developed by Southwest Research Institute (SwRI) to actively evaluate the condition of protective coatings used to prevent corrosion and structural damage.

• Automatic connection to system when sensors are in range of a wireless system

• Base station reconnects to cell phone network in the event of power interruption

• Sensors store data when out of range of the network and upload data when network is in range

• Assets can be used and do not have to remain stationary or in storage

• Sensor packages are water resistant and designed to withstand impacts

Field deployed reader node		Deployed coating degradation sensor on water tank trailer
System schematic showing sensor nodes that collect data and transmit through reader nodes to a base station where data is uploaded to a web portal

For more information about the coating degradation sensor (CDS) capabilities at SwRI or how you can contract with SwRI, please contact Garth Tormoen at gtormoen@swri.org or (210) 522-2645, or Elizabeth Trillo, Ph.D., at etrillo@swri.org or (210) 522-4210.