Li2CO3掺杂0.98(K0.5Na0.5)NbO3-0.02AETiO3陶瓷的介电与压电性能-陕西师范大学学报期刊社网站

陕西师范大学学报（自然科学版）

物理学

Li2CO3掺杂0.98(K0.5Na0.5)NbO3-0.02AETiO3陶瓷的介电与压电性能

陈宏，刘鹏*，门高丽，丁兰芳

(陕西师范大学物理学与信息技术学院，陕西西安 710062)

陈宏,女,硕士研究生,研究方向为无铅压电电子陶瓷.

摘要:

采用常规电子陶瓷工艺，制备了1.0 % Li2CO3掺杂的0.98(K0.5Na0.5)NbO3-0.02AETiO3 (AE=Mg、Ca、Sr和Ba)陶瓷(NKN-AET-Li). X射线衍射图谱(X-ray diffraction: XRD)显示所有样品均为钙钛矿结构，其中NKN-CaT-Li和NKN-SrT-Li陶瓷在室温下为正交-四方共存相，同时具有高的相对密度(>96%)；Li2CO3的掺杂提高了NKN-AET-Li陶瓷的居里温度(Tc≥400 ℃)，并明显降低了其正交-四方相变温度To-t；NKN-CaT-Li和NKN-SrT-Li陶瓷室温下具有比较高的压电性能(d33=197 pC/N，243 pC/N；kp=0.32，0.34)，并且其介电及压电性能在50～200 ℃温度范围内均表现出优良的热稳定性.

关键词：

相变；陶瓷；压电性能；钙钛矿

收稿日期：

2009-01-05

中图分类号：

O552.6

文献标识码：

文章编号：

1672-4291(2009)04-0029-05

基金项目：

国家自然科学基金资助项目(50872078)

Doi:

Electrical Properties of 0.98(K0.5Na0.5)NbO3-0.02AETiO3 piezoceramics doped with Li2CO3

CHEN Hong, LIU Peng*, MEN Gao-li, DING Lan-fang

(College of Physics and Information Technology, Shaanxi Normal University, Xi′an 710062, Shaanxi, China)

Abstract:

The lead-free piezoceramics ceramics 0.98(K0.5Na0.5)NbO3-0.02AETiO3 (AE=Mg, Ca, Sr and Ba) doped with 1.0 wt.% Li2CO3 (NKN-AET-Li) are prepared by the conventional solid-state reaction method. The X-ray diffraction (XRD) spectra show that the samples possess perovskite structure. NKN-CaT-Li and NKN-SrT-Li ceramics are coexistence of orthorhombic and tetragonal phases with a high relative density (> 96%) at room temperature. Addition of Li2CO3 obviously increases the Curie temperature(Tc≥ 400 ℃) and decreases the orthorhombic-tetragonal polymorphic phase transition temperature (To-t) for all NKN-AET-Li systems. At room temperature, NKN-CaT-Li ceramics (d33=197 pC/N, kp=0.32) and NKN-SrT-Li ceramics (d33=243 pC/N, kp=0.34) obtain a good piezoelectric properties. Dielectric and piezoelectric properties of NKN-CaT-Li and NKN-SrT-Li remain stable within a temperature range from 50 ℃ to 200 ℃.

KeyWords:

phase transitions; ceramics; piezoelectric properties; perovskites