Abstract
Lead-free ceramics (K0.5Na0.5)1-xLix(Nb1-ySby)O3have been prepared by an ordinary sintering technique. Li+and Sb5+diffuse into the K0.5Na0.5NbO3lattices to form a solid solution with the perovskite structure. The substitution of Li+increases the Curie temperature Tcand shifts the ferroelectric tetragonal-ferroelectric orthorhombic phase transition (TO-T) to low temperatures. On the other hand, the substitution of Sb5+decreases Tcand has a minor effect on TO-T. The coexistence of the orthorhombic and tetragonal phases at x ≤ 0.06 and y ≤ 0.06 near room temperature and the strong covalence of Sb lead to significant improvements in the piezoelectric properties. For the (K0.5Na0.5)0.94Li0.06(Na0.94Sb0.06)O3ceramic, piezoelectric constant d33≤ 212 pC N-1, planar and thickness electromechanical coupling factors kP≤ 46% and kt≤ 47% and Tc≤ 358 °C. The donor-type doping of BaCO3, SrCO3or Bi2O3leads to further enhancements of the piezoelectric and ferroelectric properties.
Original language | English |
---|---|
Article number | 036 |
Pages (from-to) | 3500-3505 |
Number of pages | 6 |
Journal | Journal of Physics D: Applied Physics |
Volume | 40 |
Issue number | 11 |
DOIs | |
Publication status | Published - 7 Jun 2007 |
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Acoustics and Ultrasonics
- Surfaces, Coatings and Films