PZT陶瓷材料θ相变的序参量

Study on Order Parameter of Lead Zirconate Titanate during θ Phase Transition

PbZr1-xTixO3(PZT)的θ相变是氧八面体绕[111]轴转过一微小角度θ引起的,由于前人对相变中晶体学原胞的选取不合适,所以不能正确说明晶体结构对称性的变化。本文根据居里原理,分析了相变前后对称性的变化,得出其序参量是一个三阶全对称的极张量,并给出具体的数学形式。

The θ phase transition in lead zirconate titanate（PZT）is driven by the rotation of the oxygen octahedral around [111] cubic axes.In the most previous papers,it is unsuitable selecting the unit cell of PZT,which cannot reflect the change of the crystal structure symmetry.According to the Curie principle,the symmetry changes during phase transition are discussed,and a third-order complete symmetry polarization tensor is put forward as the order parameter.