锌铌酸铅-锆钛酸铅(PZN-PZT)压电陶瓷和陶瓷纤维的制备

以乙酸铅、丙酸锌、五乙氧基铌、四丙氧基锆和四正丁氧基钛为原料,用溶胶-凝胶法制备了锌铌酸铅-锆钛酸铅(PZN-PZT)凝胶纤维.该纤维经热解、烧结后成为直径约25μm的陶瓷纤维.陶瓷纤维的表面和断面形貌的电子扫描图像显示:该陶瓷纤维均匀致密,呈圆柱形.X射线分析表明:烧结温度影响陶瓷的晶相纯度.当烧结温度高于1250℃时,该陶瓷及陶瓷纤维呈现纯净的钙钛矿晶相.阿基米德法测得陶瓷和陶瓷纤维的密度分别为7.70×10³kg/m³和7.80×10³kg/m³.对陶瓷含量为63%的PZN-PZT陶瓷纤维/环氧树脂1-3复合材料压电片,测得其机电转换常数kt、压电常数d₃₃和相对介电常数ε分别为:0.65、403pC/N和1300.以溶胶-凝胶法制备的超细粉体为原料烧结成的PZN-PZT陶瓷,其k_t、d₃₃和ε分别为0.48、600pC/N和2627.

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 k_t, piezoelectric coefficient d₃₃ and relative permittivity ε of the PZN-PZT fiber/epoxy 1-3 composite disk with 63% fibers loaded are 0.65, 403 pC/N and 1300, respectively. The k_t, d₃₃ and ε of the PZN-PZT ceramics made from the sol-gel powder are 0.48, 600 pC/N and 2627, respectively.