Phase-composition dependent domain responses in (K0.5Na0.5)NbO3-based piezoceramics
| Autor: | Zhongming Fan, Shujun Zhang, Xiaoli Tan |
|---|---|
| Rok vydání: | 2020 |
| Předmět: |
010302 applied physics
Phase transition Phase boundary Materials science Poling 02 engineering and technology 021001 nanoscience & nanotechnology Microstructure 01 natural sciences Piezoelectricity Tetragonal crystal system visual_art Phase (matter) 0103 physical sciences Materials Chemistry Ceramics and Composites visual_art.visual_art_medium Ceramic Composite material 0210 nano-technology |
| Zdroj: | Journal of the European Ceramic Society. 40:1217-1222 |
| ISSN: | 0955-2219 |
| Popis: | Lead-free (K0.5Na0.5)NbO3-based (KNN) piezoceramics featuring a polymorphic phase boundary (PPB) between the orthorhombic and tetragonal phases at room temperature are reported to possess high piezoelectric properties but with inferior cycling stability, while the ceramics with a single tetragonal phase show improved cycling stability but with lower piezoelectric coefficients. In this work, electric biasing in-situ transmission electron microscopy (TEM) study is conducted on two KNN-based compositions, which are respectively at and off PPB. Our observations reveal the distinctive domain responses in these two ceramics under cyclic fields. The higher domain wall density in the poled KNN at PPB contributes to the high piezoelectric properties. Upon cycling, however, a new microstructure feature, “domain intersection”, is directly observed in this PPB composition. In comparison, the off-PPB KNN ceramic develops large domains during poling, which experience much less extent of disruption during cycling. Our comparative study provides the basis for understanding the relation between phase composition and piezoelectric performance. |
| Databáze: | OpenAIRE |
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