Effect of Nb₂O₅ Addition on the Physical and Electrical Properties of Lead-Free (Na_0.5Bi_0.5)TiO₃ -Ba(Sn_0.08Ti_0.92)O₃ Ceramics

Abstract:

In this paper, (Na0.5Bi0.5)TiO3 -based solid solutions were studied to improve piezoelectric properties as those found in the PbZrO3-PbTiO3 (PZT)-based ceramics. The 0.98(Na0.5Bi0.5)TiO3 -0.02Ba(Sn0.08Ti0.92)O3 (0.98NBT-0.02BST) ceramics with the addition of 0~2.0 wt.% Nb2O5 have been prepared following the conventional mixed oxide process. X-ray diffraction analysis revealed that, during sintering, all of the Ba(Sn0.08Ti0.92)O3 diffuse into the lattice of (Na0.5Bi0.5)TiO3 to form a solid solution, in which a hexagonal phase with a perovskite structure was found. For 0.98NBT-0.02BST ceramics with the addition of 0.5 wt.% Nb2O5, the electromechanical coupling coefficients of the planar mode kp and the thickness mode kt reach 0.12 and 0.28, respectively, at the sintering of 1100oC for 3 h. The ratio of thickness coupling coefficient to planar coupling coefficient is 2.3. It is obvious that 0.98NBT-0.02BST ceramics by adding low quantities of Nb2O5 are one of the promising lead-free ceramics for high frequency electromechanical transducer applications.

• Periodical: Advanced Materials Research (Volumes 393-395)
• Pages: 72-75
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.393-395.72
• Online since: November 2011
• Authors: Chun Huy Wang
• Keywords: Dielectric Property, Electromechanical Transducer, Lead-Free Piezoceramic, Piezoelectric Properties, Poling, Sintering

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94NBT-0. 06BaTiO3 [1] 560.

28.

49.

[1] 75.

99NBT-0. 01CaTiO3 [2] 236.

376.

513.

[1] 36.

98NBT-0. 02BiScO3 [3] 431.

144.

8NBT-0. 2(Bi0. 5K0. 5)TiO3 [5] 1030.

27.

42.

[1] 56.

87NBT-0. 13(Sr0. 5Ca0. 5)TiO3 [6] 583.

12.

30.

[2] 5.

99NBT-0. 01Ba(Ti0. 96Zr0. 04)O3 [7] 553.

14.

51.

[3] 6 (a) 0 wt% (b) 0. 3 wt% (c) 0. 5 wt% (d) 1. 0 wt% (e) 2. 0 wt% Fig. 1: SEM images of 0. 98NBT-0. 02BST ceramics with addition of different Nb2O5 doping after sintering at 1100°C for 3 h: (a) 0 wt% (b) 0. 3 wt% (c) 0. 5 wt% (d) 1. 0 wt% (e) 2. 0 wt%. Bar=10 μm Fig. 2: XRD patterns of 0. 98NBT-0. 02BST Fig. 3: The measured density of 0. 98NBT-0. 02BST ceramics with addition of different Nb2O5 ceramics as a function of Nb2O5 addition. doping. Fig. 4: The kp and kt of 0. 98NBT-0. 02BST Fig. 5: The poled dielectric constant of 0. 98NBT ceramics as a function of Nb2O5 addition. -0. 02BST ceramics as a function of Nb2O5 addition. Fig. 6: Mechanical Quality factor of 0. 98NBT Fig 7: Dielectric loss tangent of 0. 98NBT-0. 02BST -0. 02BST ceramics with addition of different ceramics with addition of different Nb2O5 doping. Nb2O5 doping.

DOI: 10.1007/s10832-008-9552-9