title: Acoustic non-linearity for defect selective imaging.
abstract: Non-linear acoustic effects are of increasing interest in close-to-application research in which mostly ultrasonic frequencies above 1 MHz are used. If the excitation frequency is reduced, one can use high power excitation performed locally by a piezoceramic stack actuator that provides much higher vibration amplitudes. The combination of this excitation with a scanning laser interferometer provides a system for rapidly imaging non-linearities and thereby selectively detecting defects in most kinds of materials. This contribution presents various experimental results showing the potential of this new technique.
authors.affiliation: Department of Non-destructive Testing (IKP-ZFP), Institute of Polymer Testing and Polymer Science (IKP), University of Stuttgart, Germany. krohn@ikp.uni-stuttgart.de
authors.forename: N
authors.initials: N
authors.lastname: Krohn
authors.forename: R
authors.initials: R
authors.lastname: Stoessel
authors.forename: G
authors.initials: G
authors.lastname: Busse