Enhancement of Q(m) by co-doping of Li and Cu to potassium sodium niobate lead-free ceramics
Lead-free piezoelectric ceramics KNN modified by Li-substitution and CuO addition have been synthesized, and the piezoelectric and dielectric properties were measured. A morphotropic phase boundary (MPB) between orthorhombic and tetragonal phases was formed with Li-substitution. The co doping of Li...
Veröffentlicht in: | IEEE transactions on ultrasonics, ferroelectrics, and frequency control. - 1986. - 55(2008), 5 vom: 01. Mai, Seite 980-7 |
---|---|
1. Verfasser: | |
Weitere Verfasser: | , , |
Format: | Online-Aufsatz |
Sprache: | English |
Veröffentlicht: |
2008
|
Zugriff auf das übergeordnete Werk: | IEEE transactions on ultrasonics, ferroelectrics, and frequency control |
Schlagworte: | Journal Article Research Support, Non-U.S. Gov't Lead 2P299V784P Copper 789U1901C5 Lithium 9FN79X2M3F |
Zusammenfassung: | Lead-free piezoelectric ceramics KNN modified by Li-substitution and CuO addition have been synthesized, and the piezoelectric and dielectric properties were measured. A morphotropic phase boundary (MPB) between orthorhombic and tetragonal phases was formed with Li-substitution. The co doping of Li and Cu markedly enhanced the mechanical quality factor (Q(m)) in comparison with the sole doping of Li and Cu. Anomalous anti ferroelectric-like hysteresis curves were observed in 2 mol% CuO-doped ceramics. The anti-ferroelectric-like curves were changed to that of normal ferroelectrics following poling. A model based on the formation of the internal bias field (Ei) due to the movements of space charges was proposed to explain these phenomena. It was considered that the Ei stabilized the spontaneous polarization (Ps) and suppressed the domain wall motion to enhance the Q(m). The highest Qm obtained in this study was 742. The [(Na0(0.5)K0(0.5))(0.96)Li0(0.04) ] NbO(3) + 0.45 mol% CuO ceramics showed a high Q(m) value of 414 with a high piezoelectric constant d(33) of 100 pC/N |
---|---|
Beschreibung: | Date Completed 08.07.2008 Date Revised 19.11.2015 published: Print Citation Status MEDLINE |
ISSN: | 1525-8955 |
DOI: | 10.1109/TUFFC.2008.743 |