Ultrasonic guided waves for corrosion monitoring in cylindrical geometries

Abstract

In the area of Non Destructive Testing, Ultrasonic testing using wave propagation is an emerging field. Ultrasonic testing uses transmission of high frequency sound waves into a material to detect imperfections or to locate changes in material properties. This paper presents the use of pulse echo technique to detect effect of corrosion damage in steel bars. Testing of rods is done in air by placing the transducer in direct contact with one end of the rod where the wave travels through the rod from the transducer with the help of couplant (ultrasonic gel). The comparison of signatures in healthy rods and in rods damaged to various extents, in the form of number of days of corrosion, leads to damage diagnosis. Also, a successful correlation between ultrasonic voltage, weight loss due to corrosion and in situ strength has been attempted.