| About this Abstract |
| Meeting |
MS&T22: Materials Science & Technology
|
| Symposium
|
Journal of the American Ceramic Society Awards Symposium
|
| Presentation Title |
Observation of the Electromechanical Responses of (Na,K)NbO3 under Combined External Mechanical and Thermal Fields |
| Author(s) |
Neamul Hayet Khansur, Alexander Martin, Keiichi Hatano, Kenichi Kakimoto, Dominique De Ligny, Kyle Grant Webber |
| On-Site Speaker (Planned) |
Alexander Martin |
| Abstract Scope |
For (Na,K)NbO3 based systems, the monoclinic (or orthorhombic) to tetragonal phase boundary plays an important role on the overall electromechanical response. This phase boundary can be shifted via external thermal, electrical, and mechanical fields, which in return has an effect on the ferroelectric and piezoelectric response. As such, it is important to understand the processes behind these changes, as in applications for ferroelectric materials, large thermal electrical, and mechanical fields are typically applied to the electro-active material. At first, the influence of thermal and compressive mechanical fields on the small-signal relative permittivity and direct piezoelectric coefficient of polycrystalline Li-modified (Na0.5K0.5)NbO3 will be discussed. Interestingly, anomalies occurred in both the dielectric and piezoelectric properties in the vicinity of the monoclinic-tetragonal (M-T) phase boundary. To reveal changes to the crystallographic phase of Li-modified (Na0.5K0.5)NbO3 under the same fields, in situ combined temperature- and uniaxial compressive stress-dependent Raman spectroscopy was used. |