Ultrasonic non-destructive testing of adhesive bonded aluminum plates

Abstract

Ultrasonic wave technique has been proven to be an effective method for adhesive bond integrity evaluation of isotropic materials. Short ultrasonic pulsed waves with center frequencies ranging from 5- 7 MHz are launched into adhesive bonded aluminum plates to detect internal flaws. Shear wave is generated by using normal compressional probe attached to a perspex wedge which allows the sample to be scanned easily without requiring of immersion liquid. The ultrasonic wave is generated through the adhesive bonded aluminum to measure non-destructively the adhesive layer of aluminum wafer (aluminum-epoxy-aluminum) and the aluminum plates for detection of simulated defect. The resulted wave patterns of adhesively joint metal plates are studied and analysed. The measurement was carried out to evaluate the quality of bond, in the existence of gas porosity and the existence of foreign material between adhesive plates. The results of this experiment show that the ultrasonic wave generated for different conditions of bonds gives distinctive type which enables to distinguish the traveled wave in different media.