Nondestructive corrosion detection using fiber optic photoacoustic ultrasound generator

• A novel nondestructive corrosion detection mechanism is proposed.
• Fiber optic ultrasound generator is designed and fabricated for this experiment.
• Rebars with different corrosion rates are prepared with electrochemical process.
• We report an effective mechanism in detecting the rebar corrosion level.

Ultrasonic technologies have been widely used in nondestructive and noninvasive testing applications in industry. In this paper, a study on novel nondestructive corrosion detection mechanism with fiber optic photoacoustic ultrasound generator is conducted. The presented corrosion detection mechanism features compact device size (ideal for embedded optical fiber applications), non-contact approach, stable performance, and high spatial resolution. The principle of ultrasonic corrosion detection is introduced in the first section. The experimental procedure for simulation and acceleration of the sample corrosion by using the electrochemical process is also presented. Three steel reinforced rebar samples were prepared with different corrosion rates. The rebar samples were characterized to demonstrate that our mechanism is an effective tool in detecting the corrosion level of steel rebar samples.