Method of Correcting the Ultrasonic Thickness Measurement Error Caused by Roughness of Test Surfaces

Abstract

Experiments comparing the measured value of ultrasonic thickness measurements and mechanical measurements on rough corroded materials without flattening the test surface were carried out. An average measurement error of from +0.6mm to +2.2mm was found in the ultrasonic measurements. To address this problem, an error correction method using surface echo duration was proposed. A 2.25MHz broadband type transducer was suitable for the measurement and the proposed method can also be applied to a painted test surface.