Identification of Areas of Absence of Adhesive Bonding between Layers in Multilayer Structures

摘要

The theoretical foundations of the acoustic impedance method for controlling multilayer structures by means of a self-vibration mode are considered. It is shown that the self-vibration mode allows the range of application of the impedance method to be significantly extended because of the possibility of controlling of new material types, to halve a deep uncontrolled area, and to control structures—which was previously impossible by the impedance method—by means of one-way access from a thicker layer.