Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
5438819 | Ceramics International | 2017 | 11 Pages |
Abstract
(1âx)[(K0.44Na0.52Li0.04)(Nb0.84Ta0.10Sb0.06)O3]-x[(Ba0.85Ca0.15)(Ti0.90Zr0.10)O3]; (abbreviate to (1âx)KNLNTS-xBCTZ) lead-free piezoelectric ceramics were prepared via the solid state combustion technique and the effects of adding BCTZ compound (0â¤xâ¤0.030 wt%) on the phase formation, morphology and electrical behavior of the compound ceramics were investigated. The X-ray diffraction (XRD) results at room temperature of all samples exhibited a single perovskite phase and the BCTZ efficiently diffused into the KNLNTS lattice during the sintering process to produce a solid solution. The crystal structure of these ceramics changed from O+T phases to higher T phase (0â¤xâ¤0.020) and then began to change to a cubic phase when the x content increased from 0.025 to 0.030. A polymorphic phase transition (PPT) of (1âx)KNLNTS-xBCTZ ceramics was observed at an x content of 0.015 and the ratio of the orthorhombic and tetragonal phase was close to equal. Adding BCTZ compound at a ratio ⤠0.015 promoted better morphology and higher densification. When the BCTZ compound was > 0.015, the microstructure and density of the samples deteriorated. The TO-T and TC of (1âx)KNLNTS-xBCTZ samples reduced continuously with increasing x content. Moreover, the (1âx)KNLNTS-xBCTZ showed a typical relaxor ferroelectric behavior with high BCTZ content. The optimum electrical properties, such as; the highest dielectric behavior (εr at Tr = 2194 and εm at TC = 6812), excellent ferroelectric properties (Pr = 27.9 µC/cm2 and EC= 9.9 kV/cm) and the highest d33 (295 pC/N) were obtained by the sample with x content of 0.015 wt%, this sample composition was confirmed to be in the PPT region. The addition BCTZ is a new alternative for improving densification, microstructure, ferroelectric and piezoelectric properties of KNLNTS ceramics.
Related Topics
Physical Sciences and Engineering
Materials Science
Ceramics and Composites
Authors
Chittakorn Kornphom, Thanya Udeye, Prasit Thongbai, Theerachai Bongkarn,