Electrical and Physical Properties of Lead-Free (Na_0.5K_0.5)NbO₃- Bi_0.5(Na_0.93K_0.07)_0.5TiO₃ Ceramics

Abstract:

Extending the investigations on (Na0.5K0.5)NbO3-based solid solution for lead-free piezoelectric ceramics, this paper consider the complex solid-solution system (Na0.5K0.5)NbO3–Bi0.5(Na0.93K0.07)0.5TiO3 [NKN-BNKT]. (Na0.5K0.5)NbO3 with 2 ~ 6 mol% Bi0.5(Na0.93K0.07)0.5TiO3 has been prepared following the conventional mixed oxide process. A morphotropic phase boundary (MPB) between orthorhombic (O) and rhombohedral (R) was found at the composition 0.98NKN-0.02BNKT with correspondingly enhanced dielectric and piezoelectric properties. The electromechanical coupling factor and dielectric constant are higher for compositions near the MPB. The dielectric constant (KT33), planar coupling coefficient (kp) and thickness coupling coefficient (kt)of 0.98NKN-0.02BNKT ceramics were 1040, 47% and 48%, respectively.

• Periodical: Key Engineering Materials (Volumes 512-515)
• Pages: 1351-1354
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.512-515.1351
• Online since: June 2012
• Authors: Chun Huy Wang
• Keywords: Dielectric Property, Electromechanical Transducer, Lead-Free Piezoceramics, Piezoelectric Properties

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