Microstructure and Piezoelectric Properties of [(K_0.5Na_0.5)_1-xLi_x](Nb_1-yTa_y)O₃ Lead-Free Piezoelectric Ceramics

Abstract:

Li+ and Ta5+ modified lead-free piezoelectric ceramics [(K0.5Na0.5)1-xLix](Nb1-yTay)O3 have been prepared by an ordinary sintering technique. Effect of Li+ and Ta5+ on microstructure and piezoelectric properties of the ceramics was systematically studied. A morphotropic phase boundary between orthorhombic and tetragonal phases is identified in the composition range of (0.02≤x≤0.04, 0.15≤y≤0.25), which can enhance electrical properties of [(K0.5Na0.5)1-xLix](Nb1-yTay)O3 ceramics. The Curie temperature TC of these ceramics is lower than that of pure (K0.5Na0.5)NbO3 ceramics, but the temperature of orthorhombic to tetragonal phase transition TO-T of the former is higher than that of the latter. TC and TO-T both decrease as the content of Ta5+ increases. With the addition of Li+ increasing, TC increases. The optimal piezoelectric properties are obtained at (x, y)=(0.03, 0.20): piezoelectric constant d33 is 192pC/N; the electromechanical coefficient of the planar mode kp is 44%; room temperature dielectric constant εr is 1049, and the corresponding mechanical quality factor Qm is 49.

• Periodical: Advanced Materials Research (Volumes 156-157)
• Pages: 1522-1527
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.156-157.1522
• Online since: October 2010
• Authors: Bei Xu, Feng Gao, Bo Li, Liang Liang Liu, Zhen Qi Deng
• Keywords: Lead-Free Ceramic, Microstructure, Morphotropic Phase Boundary, Piezoelectric Properties

References

[1] F. Gao, H.J. Zhang, X.C. Liu, W.M. Wang and C.S. Tian: Piezoelectrics & Acoustooptics Vol. 28 (2006), p.60. (In Chinese).

[2] L. Wu, D.Q. Xiao, Y. Sun, M. Chen, D.M. Lin and J.G. Zhu: Journal of Functional Materials Vol. 38 (2007), p.1400. (In Chinese).

[3] Y. Watanabe, Y. Hiruma, H. Nagata and T. Takenaka: Ceramics International Vol. 34 (2008), p.761.

[4] F. Gao, C.S. Zhang, X.C. Liu, L.H. Cheng and C.S. Tian: Journal of the European Ceramic Society Vol. 27 (2007), p.3453.

[5] T. Takenaka and H. Nagata: Journal of the European Ceramic Society Vol. 25 (2005), p.2693.

[6] W.F. Liu and X.B. Ren: Physical Review Letters Vol. 103 (2009) , pp.257602-1.

[7] N. Nanakorn, P. Jalupoom, N. Vaneesorn and A. Thanaboonsombut: Ceramics International Vol. 34 (2008), p.779.

DOI: 10.1016/j.ceramint.2007.09.024

[8] Y. Sun, D.Q. Xiao, L. Wu, M. Chen, D.M. Lin and J.G. Zhu: Functional Materials Vol. 38 (2007), p.1225. (In Chinese).

[9] D.M. Lin, D.Q. Xiao, J.G. Zhu, P. Yu and H.J. Yan: Functional Materials Vol. 34 (2003), p.615. (In Chinese).

[10] K. Matsumoto, Y. Hiruma, H. Nagata and T. Takenaka: Ceramics International Vol. 34 (2008), p.787.

[11] L.H. Li, J.X. Deng, J. Chen, R.B. Yu, L.J. Qiao and X.R. Xing: Journal of Alloys and Compounds Vol. 471 (2009), p.428.

[12] H.J. Zhang, M. Zhao, C.S. Zhang, F. Gao and C.S. Tian: Electronic Components & Materials Vol. 25 (2006), p.41. (In Chinese).

[13] L.M. Zheng, J.F. Wang, G.Z. Zang, P. Qi and J. Du: Electronic Components & Materials Vol. 25 (2006), p.21. (In Chinese).

[14] X.Y. Sun, J. Chen, R.B. Yu, C. Sun, G.R. Liu, X.R. Xing and L.J. Qiao: Journal of the American Ceramic Society Vol. 92 (2009), p.130.

[15] Y. Saito, H. Takao, T. Tani, T. Nonoyama, K. Takatori, T. Homma, T. Nagaya and M. Nakamura: Nature Vol. 432 (2004), p.84.

DOI: 10.1038/nature03028

[16] R.Z. Zuo, J. Fu and D.Y. Lv: Journal of the American Ceramic Society Vol. 92 (2009), p.283.

[17] R.Z. Zuo, J. Fu, S. Su, X.S. Fang and J.L. Cao: Journal of Material Science: Mater Electron: Vol. 20 (2009), p.212.

[18] Y. G. Lv, C. L. Wang, J. L. Zhang, L. Wu, M.L. Zhao and J.P. Xu: Materials Research Bulletin Vol. 44 (2009), p.284.

[19] J. Fu, R.Z. Zuo, X.S. Fang and K. Liu: Materials Research Bulletin Vol. 44 (2009), p.1188.

[20] J. Fu, R.Z. Zuo, X.H. Wang and L.R. Li: J. Phys. D: Journal of Applied Physics Vol. 42 (2009), pp.012006-1.

[21] Y.P. Guo, K. Kakimoto and H. Ohsato: Applied Physics Letters Vol. 85 (2004), p.4121.