A flexible ultrasonic array incorporating a platelet composite transmitter-theory and experiment

The surface conforming qualities of flexible ultrasonic arrays makes them ideally suited to non-destructive testing (NDT) of non-planar and curved surface topographies. The proposed array is a hybrid device that combines the transmission sensitivity of ceramic/polymer composites, with the high bandwidth reception properties of PVDF. Experimental impedance characteristics and thickness mode modelling techniques suggest that a transmit element incorporating ceramic platelets may provide a compromise between flexibility and ease of manufacture. A surface scattering model has been developed that may be used to assess the influence of factors such as interelement spacing on the array´s potential imaging performance. This paper discusses the rationale behind the design procedure. An array is then constructed based on this analysis and a series of experimental results is presented