A novel ultrasonic array incorporating composite transducer technology

A new type of ultrasonic array transducer that incorporates the high bandwidth reception properties of PVDF with the greater transmission sensitivity of a composite transducer is presented. Through careful choice of epoxy phase for the composite polymer matrix and a novel electroding technique, the composite maintains its normal transmission sensitivity but with the added advantage of practical flexibility. The authors consider the theoretical and practical design of the array structure with the piezoelectric process within the composite and with the choice of ceramic pillar width-to-height (W /H) ratio being based upon a series of finite element modeling results. The array´s operation is evaluated by (a) a modified facet ensemble model which is used to predict the backscattered response from a variety of test specimens possessing surface fatigue cracks and arbitrary surface variations and (b) experimental imaging performance