The increasing demand in industry to produce solid-solid bonds has given stimulus to development of methods of nondestructive testing of such products [1]. The difficulty is to discriminate and quantitatively describe imperfect interfaces by non-destructive measurements. In adhesive bond technology the surface preparation of the adherend is most critical [1]. Ultrasonic measurements seem most promising for NDE of bonds since they are extremely sensitive to the state of contact at the interface and can be utilized to directly measure interfacial properties.