Abstract
To date, the non-destructive testing (NDT) is mainly realized by using ultrasonic inspection, X-ray inspection, eddy-current testing and magnetic-particle testing, etc. These inspection methods have high accuracy and reliability. However, they also have some disadvantages. For instance, a long inspection time is usually needed because the inspection area in these methods is relatively narrow at one time. To overcome this weak point, the damage inspection techniques with Lamb waves which can detect a wide area due to their long-distance propagation ability are actively studied in recent years. In the present work, based on an inverse algorithm, a tomographic reconstruction technique of damage image, e.g., the area and shape of a damage, by using the amplitude decrease of the transmitted Lamb wave through the damage, is proposed. From the obtained experimental results, the validity of the proposed method for reconstructing the damage image is verified. This method can be also applicable to the case where multiple damages exist in the inspected area.
