Remote Non-Contact Ultrasonic Testing of Composite Materials

摘要

Ultrasonic testing is extensively utilized for integrity verification ofcomposite material. In advanced applications and for composite process controlit is advantageous to perform non-contact ultrasonic measurements that do notrequire traditional ultrasonic coupling and contact requirements. The new noncontactultrasonic testing methods using laser ultrasound and air/gas coupledultrasonic transducers enable in-situ evaluation of composite process such asfiber placing. This hybrid ultrasonic configuration has been extended tocomposite applications that are not possible with the conventional ultrasonicmethods. Non-contact ultrasonic methods are adapted for surface wave testing inMHz frequencies that enable defect detection in surface plies of the compositematerial. Surface wave ultrasonic methods are demonstrated to be sensitive tocomposite process defects and are affected by ply disbonds or lack of compositeconsolidation. Non-contact ultrasonic approach enables on-line process control.The non-contact test configuration has been packaged into a compact remote testhead.