Numerical simulation of ultrasound NDE for adhesive bond integrity

A multiple attack strategy (analytical, numerical, and experimental investigations) has been developed for the evaluation of adhesive bond integrity. This coupled approach capitalizes on the ability of numerical simulations to provide a transparent viewing window to the underlying physics at the interface. A finite element model solves the transient elastodynamic equation of motion subject to realistic boundary and initial conditions. Three material regions were identified in the model. The numerical predictions of the ultrasonic wave propagations include reflections and trapped waveforms within the sandwiched material. Substantial differences are noted between bonded and disbond regions. These results show excellent agreement with theory and with results measured experimentally