文章信息/Info

Title:

Progress in Phase Field Simulations of Piezoelectric Materials

作者:

柯小琴;  任曉兵;  王云志

 西安交通大學前沿科學研究院

Author(s):

Ke Xiaoqin;  Xiaobing Ren;  Wang Yunzhi

Frontier Institute of Science and Technology, Xi’an Jiaotong University

關鍵詞:

 ; 壓電材料; 準同型相界; 相場動力學;  計算機模擬

DOI:

10.7502/j.issn.1674-3962.2016.06.05

文獻標志碼:

A

摘要:

 壓電材料是一種能夠在機械能和電能之間互相轉換的材料，在制動器，傳感器等器件上應用廣泛。高性能壓電材料通常都出現在鐵電固溶體相圖的準同型相界附近，因此研究準同型相界附近出現高壓電性能的機理對于開發新的壓電材料至關重要。本文主要綜述了利用相場模擬的手段研究準同型相界附近壓電材料的微觀結構以及高壓電性能機理的進展。在微觀結構方面，我們通過相場模擬得到了準同型相界附近與實驗類似的階梯式納米疇結構，并且發現這些納米疇是最近實驗發現的單斜相，該單斜相可以由長程靜電能和彈性能所穩定。在壓電性能方面，我們通過相場模擬發現，準同型相界附近的高壓電性能主要來自于極化旋轉而非疇壁移動的貢獻。

Abstract:

Piezoelectric materials are materials that can convert mechanical energy to electric energy and vice versa and they are widely used in transducers and actuators. The best piezoelectricity normally appear at the so called morphotropic phase boundary(MPB) in the phase diagram of ferroelectric solid solutions. Thus understanding the mechanism of good piezoelectric properties at the MPB can guide designing new piezoelectric materials. This review summarized the progress in simulating the microstructure of piezoelectric materials at the MPB as well as the mechanism of good piezoelectric property there through phase field simulations.  On the microstructure, we obtained hierarchical nanodomain structure as observed by experiments by phase field simualation and our work shows that these nanodomains are the newly discovered monoclinic phase and this new phase is stabilized by long range electrostatic energy and elastic energy. On the piezoelectric property, we showed by phase field simulation that the good piezoelectric property appearing at the MPB mainly comes from the contributions from polarization rotation rather than domain wall movement.