PZT陶瓷冷烧结工艺的优化与压电性能研究

Optimization of cold sintering process and piezoelectric properties of PZT ceramics

为了提高冷烧结工艺制备的样品致密度,进而其增强压电性能,通过对PZT粉体进行表面修饰、优化PZT颗粒粒径搭配等手段室温化制备高压电系数PZT陶瓷,对PZT陶瓷冷烧结工艺进行优化。研究结果表明:通过Li2MoO4溶液对PZT原料粉体进行表面修饰,形成了厚度为150 nm的Li2MoO4包覆层,有利于冷烧结过程中颗粒重排和溶解−沉淀;采用(63,200)μm的粗颗粒和1~3μm的细颗粒搭配,使得细颗粒流动到粗颗粒桥接产生的缝隙和孔洞中,实现颗粒间紧密的连接,获得最高的密度(6.49 g/cm^3)和相对致密度(85.40%);致密度的提高使样品获得优异的介电和压电性能,在1 kHz时,相对介电常数和介电损耗分别为66.8和0.288;在110 Hz时,压电系数d33为71 pC/N。

To improve the density of samples in cold sintering process and enhance the piezoelectric properties,the high piezoelectric coefficient PZT ceramics at room temperature were prepared by surface modification of a lead zirconate titanate PZT powder and optimization of PZT particle size.The cold sintering process of PZT ceramics was optimized.The results show that a Li2MoO4 coating with a thickness of 150 nm is formed on the surface of the PZT powder,which is beneficial to the particle rearrangement and the dissolution−precipitation process during cold sintering.A combination of coarse particles(63,200)μm and fine particles 1−3μm provides a close connection between the particles due to the fine particles flowing into the gaps and holes between the coarse particles,so as to obtain a high density(6.49 g/cm^3)and relative density(85.40%).This increase in density allows the samples to obtain excellent dielectric and piezoelectric properties.For example,the relative permittivityεr and loss tangent tanδat 1 kHz are 66.8 and 0.288,respectively;and the piezoelectric coefficient d33 at 110 Hz is 71 pC/N.