A novel ((Bi0.5Na0.5)0.94Ba0.06)1- (K0.5Nd0.5) TiO3 lead-free relaxor ferroelectric ceramic with large electrostrains at wide temperature ranges
| Autor: | Xiaohu Ren, Yungui Shi, Nianshun Zhao, Huiqing Fan, Shang Gao, Jiangwei Ma |
|---|---|
| Rok vydání: | 2018 |
| Předmět: |
010302 applied physics
Phase boundary Materials science Process Chemistry and Technology Analytical chemistry Mineralogy 02 engineering and technology Dielectric 021001 nanoscience & nanotechnology 01 natural sciences Ferroelectricity Piezoelectricity Surfaces Coatings and Films Electronic Optical and Magnetic Materials Tetragonal crystal system visual_art Phase (matter) 0103 physical sciences Materials Chemistry Ceramics and Composites visual_art.visual_art_medium Ceramic 0210 nano-technology Polarization (electrochemistry) |
| Zdroj: | Ceramics International. 44:571-579 |
| ISSN: | 0272-8842 |
| DOI: | 10.1016/j.ceramint.2017.09.215 |
| Popis: | Novel ((Bi0.5Na0.5)0.94Ba0.06)1-x(K0.5Nd0.5)xTiO3(x = 0.0, 0.02, 0.04, 0.06) lead-free ceramics (BNBT–xKN) were prepared by the solid-state reaction method. The effects of A-site (K0.5Nd0.5)2+ complex-ion substitution on their phase structure, dielectric, piezoelectric, and electromechanical properties were studied. The X-ray diffraction results indicate that all compositions are located in the morphotropic phase boundary (MPB) region where the tetragonal phase coexists with the rhombohedral phase. In addition, as the KN content increases, the ferroelectric order transform to relaxor order, which is characterized by a degeneration of maximum polarization, remnant polarization and correspondingly adjusts the ferroelectric-relaxor transformation temperature (TF-R) to room temperature. Interestingly, the disruption of ferroelectric phase caused a significant improvement of strains. A maximum strain of ~ 0.52% corresponding to normalized strain of ~ 612 pm/V appeared at 85 kv/cm for the x = 0.04 composition. Particularly, the composition of x = 0.04 exhibited high electrostrains of temperature insensitivity, which remained above 0.4% and kept within 10% from ambient temperature up to 110 °C. It can be ascribed to the coexistence of non-ergodic and ergodic states in the relaxor region. As a result, the systematic investigations on the BNBT–xKN ceramics can benefit the developments of temperature-insensitive “on-off” actuators. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full Text from ScienceDirect