PZT nanocomposites reinforced by small amount of MgO

To enhance the fracture toughness of brittle lead titanate zirconate (PZT) ceramics, PZT nanocomposites with 0.1, 0.5 and 1.0 vol% MgO were fabricated by means of a conventional industrial fabrication method. Through scanning electron microscopy (SEM) observation, indentation tests and D-E hysteresis measurement, the properties of PZT/MgO nanocomposites are characterized. With the increase of additional MgO, the fracture mode of PZT/MgO nanocomposites gradually changes from intergranular to transgranular fracture and the fracture toughness is fairly enhanced. The electric coercive fields of PZT/MgO nanocomposites decrease gradually while the piezoelectric constant d₃₃ hardly changes except that of PZT-1.0 vol% MgO which decreases about 13% compared with the monolithic PZT.