Lanthanum‐Modified (1 – x)(Bi 0.8 La 0.2 )(Ga 0.05 Fe 0.95 )O 3 ·xPbTiO 3 Crystalline Solutions: Novel Morphotropic Phase‐Boundary Lead‐Reduced Piezoelectrics
2003; Wiley; Volume: 86; Issue: 12 Linguagem: Inglês
10.1111/j.1151-2916.2003.tb03617.x
ISSN1551-2916
AutoresJinrong Cheng, Richard E. Eitel, L. E. Cross,
Tópico(s)Dielectric materials and actuators
Resumo(1 – x )(Bi 0.8 La 0.2 )(Ga 0.05 Fe 0.95 )O 3 · x PbTiO 3 (BLGF‐PT) crystalline solutions have been fabricated by solid‐state reactions. BLGF‐PT has single perovskite phase structure with a rhombohedral–tetragonal (FE r ‐FE t ) morphotropic phase boundary (MPB) at a PT content of x = 0.43. Lanthanum substitution has been found to increase the insulation resistance and decrease the coercive field down to 20 kV/cm, which results in significant improvements in dielectric and piezoelectric properties of BLGF‐PT. The dielectric constant, loss tangent, Curie temperature, remnant polarization, piezoelectric d 33 constant, and planar coupling factor of 1760, 0.05, 264°C, 33 μC/cm 2 , 295 pC/N, and 0.36, respectively, have been achieved for BLFG‐PT in the vicinity of the MPB. Compared with conventional Pb(Zr,Ti)O 3 (PZT) piezoelectric ceramics, the BLGF‐PT is a competitive alternative piezoelectric material with decreased lead content.
Referência(s)