摘要：以氧化铅、氧化钛、氧化锆、氧化镧和氧化铌为原料，采用传统的固相合成工艺制备Pb0.9025La0.065(Zr0.58Ti0.42)0.975Nb0.02O3（PLZT）陶瓷粉体。研究了烧结助剂钨铜酸铅（PWC）和钨酸锂（LWC）的含量对烧结温度、陶瓷的晶相结构、微观形貌、致密度和电学性能的影响。结果表明，烧结温度在950℃~1150℃范围内，加入适量的LWC和PWC在烧结前期形成过渡液相促进烧结；在烧结后期被主晶相吸收。与LWC掺杂的陶瓷相比，PWC的掺入使得材料的压电应变常数d33、相对介电常数εr、机电耦合系数Kp较高，但同时也使得介电损耗tanδ增大；随着PWC掺入量的增加，材料的d33、Kp和εr 都先增加后减小；而陶瓷相的结构由伪立方相逐渐过渡到四方相。在1100℃烧结1小时、含4wt%PWC的样品，其居里温度Tc＝230℃，压电应变常数d33＝311 pC/N，机电耦合系数Kp＝0.44，介电常数 εr ＝2389，介电损耗tanδ＝0.04，机械品质因数Qm=67.7。
关键词：锆钛酸铅镧；压电陶瓷；钨铜酸铅；钨铜酸锂；低温烧结
Abstract:The lead lanthanum zirconate titanate Pb0.9025La0.065(Zr0.58Ti0.42)0.975Nb0.02O3 (PLZT) were prepared via the conventional mixed-oxide technique by using Pb3O4, TiO2, ZrO2, La2O3 and Nb2O5 oxides as raw materials. The effects of sintering additives Li2(W0.5,Cu0.5)O3 (LWC)& Pb(W0.5,Cu0.5)O3 (PWC) content on the sintering temperature, phase structure, micro-morphology, density and electric properties of the ceramic were investigated. The results showed that the LWC & PWC as sintering additives could form liquid phase to improve sintering process in the temperature region of 950 - 1150℃, and finally they were absorbed in the main crystalline phase. Compared with that doped with LCW, the PLZT doped with PWC showed higher piezoelectric constant d33,dielectric permittivity εr and electromechanical coefficient Kp, but they also showed a higher dielectric loss tanδ. As PWC content increased, the d33、εr and Kp firstly increased and then decreased, the crystalline phase changed from fake cubic to tetragonal structure. When the PWC content was 4wt%, the Curie temperature Tc,d33,Kp,εr, tanδ and qulity fator Qm of the samples sintered at 1100℃ were found to be 230℃, 311pC/N, 0.44, 2389, 0.04 and 67.7, respectively.
Keywords: PLZT; piezoelectric ceramics; Pb(W0.5,Cu0.5)O3; Li2(W0.5,Cu0.5)O3; low temperature sintering;
