PVDF is being used in compression wave ultrasonic transducers for some years and had also been used in arrays. It has the advantage over piezoelectric ceramics of being flexible hence bonding it to curved structure does not cause engineering problems. Its internal damping is also higher than that of ceramics so the excitation of guided waves in the film is less likely to be a problem. however, such composites are less sensitive than ceramics and they cannot be used at high temperature which may preclude its use in some structures. Recently, with adequate piezoelectric charge and voltage constants as well as good mechanical ductility has emerged for a variety of applications