PZT陶瓷中由氧空位与畴壁相互作用引起的内耗

采用低频倒置扭摆内耗仪对组分为 Pb(Zr0.7Ti0.3)O3 (PZT73)和 Pb(Zr0.3Ti0.7)O3 (PZT37) 的两种陶瓷的内耗 Q-1及振动频率的平方 f 2（正比于材料的剪切模量 G）与温度的关系进行了 测定。在纯三角相的 PZT73陶瓷中发现两个内耗峰。高温内耗峰 PM起源于材料的顺电－铁 电相变 ,低温内耗峰 P1本质上是一个宽化的 Debye峰，可归因于氧空位作用下的畴壁振荡弛豫。 对纯四方相的 PZT37陶瓷，除了 P1和 PM峰外，在 P1与 PM峰之间另有内耗峰 P2，这与 900畴附 近的氧空位团簇的弛豫有关 ,其特征可用描述强关联系统的关联态模型（ Coupling model）描述。

Internal friction due to the interaction between oxygen vacancies and domain boundaries in PZT ceramics

The internal friction Q－ 1 and the square of vibration frequency f 2(proportional to shear modulus G) were measured as a function of temperature on undoped Pb(Zr0.7Ti0.3)O3 (PZT73) and Pb(Zr0.3Ti0.7) O3 (PZT37) ceramics from 200C to 5000C. Experiments were performed on an inverted torsion pendulum at low frequencies (1～ 5Hz) .Two internal friction peaks were found in pure rhombohedral PZT73 ceramics. The high temperature peak PM, which appears at the Curie temperature, originates from the para－ ferroelec－tric phase transition. The low temperature peak P1 is a broadened Debye peak in nature, and it is contri－buted to the oscillation damping of the domain walls locked by the oxygen vacancies. For the pure tetrago－nal PZT37 ceramics, another peak P2,which appears between P1 and PM,can be well described by the coup－ling model. It is thought to be related with the relaxation of oxygen vacancy clusters near the 900 domains.