Giant strain with low cycling degradation in Ta-doped [Bi1/2(Na0.8K0.2)1/2]TiO3 lead-free ceramics

Abstract

Articles you may be interested inHierarchical domain structure of lead-free piezoelectric (Na1/2 Bi1/2)TiO3-(K1/2 Bi1/2)TiO3 single crystals J. Appl. Phys. 119, 174102 (2016); 10.1063/1.4948478Phase structure and piezoelectric properties of (1−x)K0.48Na0.52Nb0.95Sb0.05O3-x(Bi0.5Na0.5)0.9(Li0.5Ce0.5)0.1ZrO3 lead-free piezoelectric ceramics J. Appl. Phys. 119, 034101 (2016) . These values are greater than most previously reported lead-free polycrystalline ceramics and can even be compared with some lead-free piezoelectric single crystals. Additionally, this ceramic displays low cycling degradation; its electrostrain remains above 0.55% even after undergoing 10 000 cycles of 650 kV/cm bipolar fields at 2 Hz. Therefore, Ta-doped [Bi 1/2 (Na 0.8 K 0.2 ) 1/2 ]TiO 3 ceramics show great potential for large displacement devices. Published by AIP Publishing.

Large electrocaloric responses in [Bi1/2(Na,K)1/2]TiO3‐based ceramics with giant electro‐strains

“…Giant strains, 0.70% in BNKT‐2.5Nb and 0.59% in BNKT‐1.5Ta, are developed at positive peak field (50 kV/cm). These electro‐strains are consistent with the range of measured values in our previous publications . The giant strain in BNT‐based ceramics is ascribed to the reversible field induced phase transition, taking place in the ergodic relaxor which we believe to be the “relaxor ferrielectric” phase …”

“…Asymmetry is also seen in the corresponding polarization loops (not shown). Defect dipoles are speculated to be responsible for the observed asymmetry . Giant strains, 0.70% in BNKT‐2.5Nb and 0.59% in BNKT‐1.5Ta, are developed at positive peak field (50 kV/cm).…”

“…Recently, our group reported giant large‐signal piezoelectric coefficients () in two [Bi 1/2 (Na,K) 1/2 ]TiO 3 ‐based ceramics, {[Bi 1/2 (Na 0.84 K 0.16 ) 1/2 ] 0.96 Sr 0.04 }(Ti 0.975 Nb 0.025 )O 3 and [Bi 1/2 (Na 0.8 K 0.2 ) 1/2 ](Ti 0.985 Ta 0.015 )O 3 . In this study, we used the indirect measurement to characterize the ECE in both ceramics to demonstrate their potential multifunctional properties and to explore the mechanisms for ECE.…”

Large strain response with low driving field in Bi1/2Na1/2TiO3–Bi1/2K1/2TiO3–Bi(Mg2/3Nb1/3)O3 ceramics

“…With increasing the BMN concentration, T s shifts to lower temperature, while T m to higher temperature. Besides, the dielectric peaks at T m were suppressed and gradually broadened, suggesting an enhanced diffuse phase transition behavior of the 100 x BMN system …”

Modulation of electrostriction and strain response in bismuth sodium titanate‐based ceramics

“…Based on the design idea of phase boundaries, the coexistence of rhombohedral and tetragonal phases can be achieved by designing several kinds of solid solutions, with typical candidates including BNT‐BT and BNT‐BKT . After that, ions or ABO 3 compounds are often employed to modify the strain properties of BNT‐based ceramics . According to previous reports, the addition of Nb can induce a high strain in BNT‐BT ceramics, and La can also enhance the strain behavior of BNT‐BKT‐ST(SrTiO 3 ) ceramics under 60 kV/cm .…”