4I-2 Ultrasonic Pulse-Echo NDE of Adhesive Bonds in Sheet-Metal Assemblies

The development of a 20 MHz pulse-echo method for nondestructive evaluation (NDE) of adhesive bonds was undertaken to provide assurance of bond integrity in vehicle body assemblies. This new NDE method features improvements over previous methods implemented in production, and extends the range of bond evaluation effectiveness. The NDE is accomplished by the acquisition and analysis of acoustic echoes that return from bond joints that have interfaces between layers with large acoustical impedance mismatch. These echoes reverberate in the multilayered joint structures and are captured for a computer-automated analysis that provides a rapid interpretation of the indications, and subsequently yields a simplified display of the inspection results