Ultrasonic vibration method for damage detection in composite aircraft components

Abstract

A new ultrasonic vibration method has been developed for damage detection in composite aircraft components. The method is based on controlled vibrations introduced by special annular array actuators at ultrasonic frequency ranges that are above 20 kHz. It has been demonstrated that by applying different phase delays to the annular array elements and using different driving frequencies, one can use the annular array actuators to change the controlled vibrations introduced to a composite component. The controlled vibrations appear to have different sensitivity to different damage types and also boundary condition variations. Special loading functions in terms of different combinations of driving frequencies and phase delays have been identified for the detection of certain damage types in example aircraft composite components. Excellent damage sensitivity has been achieved. © The Society for Experimental Mechanics, Inc. 2012.