Title :
Relaxor ferroelectrics with lanthanum perovskites
Author :
Takenaka, Tadashi ; Kanegae, Toshio
Author_Institution :
Tokyo Univ., Chiba, Japan
fDate :
30 Aug-2 Sep 1992
Abstract :
Lanthanum perovskite compounds La(B1/2IB1/2II)O3 (BI=Ni,Co,Mg; BII=Ti) are studied as candidates for stabilizers to form perovskite-type Pb(Zn1/3Nb2/3 )O3 (PZN)-based ceramics. A conventional sintering technique is used to prepare ceramic samples with PZN-based solid solution. The ratios of the perovskite phase to the pyrochlore phase were more than 90% at 10 mol.%-modification of La(Ni1/2Ti1/2)O3 (LNT), La(Mg1/2 Ti1/2)O3 (LMT) or La(Co1/2Ti1/2)O3 (LCT). The suppression of the pyrochlore phase in these ceramics is evaluated. The transverse electrostrictive strain, S1~-0.75×10-4, is induced by an electric field of 30 kV/cm in the thickness direction in the 5 mol.%-LNT modified PZN-based ceramics. The magnitude of strain is rather small, but the strain hysteresis is very small as compared with corresponding values for piezoelectric ceramics
Keywords :
X-ray diffraction examination of materials; ceramics; cobalt compounds; crystal microstructure; dielectric hysteresis; dielectric losses; electrostriction; ferroelectric materials; lanthanum compounds; lead compounds; magnesium compounds; nickel compounds; permittivity; powder technology; sintering; zinc compounds; PbZnO3NbO3-La(CoTi)O3; PbZnO3NbO3-La(MgTi)O3; PbZnO3NbO3-La(NiTi)O3; conventional sintering technique; electric field; perovskite phase; pyrochlore phase; relaxor ferroelectrics; strain hysteresis; thickness direction; transverse electrostrictive strain; Capacitive sensors; Ceramics; Dielectric constant; Dielectric loss measurement; Dielectric measurements; Electric variables measurement; Electrostriction; Lanthanum; Relaxor ferroelectrics; Strain measurement;
Conference_Titel :
Applications of Ferroelectrics, 1992. ISAF '92., Proceedings of the Eighth IEEE International Symposium on
Conference_Location :
Greenville, SC
Print_ISBN :
0-7803-0465-9
DOI :
10.1109/ISAF.1992.300645
