Fabrication of PZN-PZT Piezoceramics and Ceramic Fibers

By using lead acetate, zinc propionate, niobium ethoxide, zirconium propoxide and titanium butoxide as precursors, zinc and niobium modified lead zirconate titanate (PZN-PZT) gel fibers were fabricated by the sol-gel method. Prolyzed and sintered, The PZN-PZT ceramic fibers with a diameter of about 25μm were obtained. The SEM micrographs show that these ceramic fibers are dense and uniform. The X-ray diffraction patterns show that sintering temperatures will affect the crystal structure of PZN-PZT ceramics. When the sintering temperature higher than 1250℃, the sintered ceramics and ceramic fibers have a pure perovskite structure. The densities of the bulk ceramic and ceramic fiber are 7.70×103kg/m3 and 7.80×103kg/m3, which were measured by Archimedes method. The electromechanical coupling coefficient kt, piezoelectric coefficient d33 and relative permittivity e of the PZN-PZT fiber/epoxy 1-3 composite disk with 63% fibers loaded are 0.65, 403 pC/N and 1300, respectively. The kt,d33 and e of the PZN-PZT ceramics made from the sol-gel powder are 0.48, 600 pC/N and 2627, respectively.