Measurement of adhesion strength using nonlinear acoustics

Weak adhesion strength or delaminations can be detected qualitatively by conventional techniques such as the determination of the interface reflection coefficient of an ultrasonic or thermal wave. However, a quantitative determination of adhesion strength is difficult. We have developed a new method using nonlinear acoustics allowing the determination of the adhesion strength of simply bonded or coated structures, as well as of more complex structures including fiber matrix composites.