Hollow piezoelectric composites

Current research activity in piezoelectric sensors and actuators is moving toward better resolution and higher power densities. Higher resolution and smaller sizes are needed in applications such as biomedical ultrasound, probes for invasive procedures, flow noise control, nondestructive testing, and automotive instrumentation. Piezoelectric transducers with enclosed hollow space offer several special advantages including low acoustic impedance, reduced mass, sensitivity to weak hydrostatic waves, and enlarged displacements through flextensional and rotational motions. This paper describes recent advances in the processing and properties of five types of hollow piezoelectric composites with the connectivity patterns 0(0)-3, 1(0)-3, 2-0-2, 3-1(0) and 2(0)-2-2(0). Piezocomposites with hollow space included within the structure clearly demonstrate the advantages of functional composites in the field of smart systems.