PZT

PZT, short for lead zirconate titanate, is a ceramic perovskite material renowned for its strong piezoelectric and ferroelectric properties. It is a solid solution with the formula Pb(Zr1−xTix)O3, where zirconium and titanium occupy the B-site of the lattice. The ratio x determines key properties; near the morphotropic phase boundary at x ≈ 0.52, the material exhibits an enhanced piezoelectric response.

PZT combines high dielectric permittivity, large piezoelectric actuation, and good environmental stability. The piezoelectric charge coefficient d33, a measure of longitudinal response, typically ranges from about 100 to over 600 pC/N depending on composition and processing. The electromechanical coupling factor kp is commonly in the range of 0.6 to 0.8. PZT can be engineered as soft (enhanced strain and sensitivity) or hard (lower losses and greater mechanical quality factor) by dopant selection. The Curie temperature, above which piezoelectricity is lost, generally falls in the broad range of 250–500°C and depends on the Zr/Ti ratio and processing.

Processing and forms: PZT is produced as dense ceramic bodies, and in multilayer devices it is stacked with internal electrodes. Thin-film PZT is grown on substrates by deposition techniques such as sputtering or sol–gel methods. Because lead content raises environmental and health concerns, manufacturing and regulatory standards restrict use in some applications, and researchers pursue lead-free piezoelectrics as alternatives.

Applications: PZT is a standard material for actuators, sensors, ultrasonic transducers (including medical imaging and nondestructive testing), buzzers, and energy harvesters. Its combination of high piezoelectric response, robustness, and processing versatility underpins widespread commercial and research use.