Orthorhombic‐pseudocubic phase transition and piezoelectric properties of (Na0.5K0.5)(Nb1−xSbx)‐SrZrO3 ceramics |
| |
| Authors: | Ku‐Tak Lee Dae‐Hyeon Kim Jong‐Seong Park Tae‐Gon Lee Sung‐Hoon Cho Su‐Jin Park Jong‐Yoon Kang Sahn Nahm |
| |
| Affiliation: | 1. Department of Materials Science and Engineering, Korea University, Seongbuk‐gu, Seoul, Korea;2. Department of Information Technology‐Nano Science, KU‐KIST Graduate School of Converging Science and Technology, Korea University, Seongbuk‐gu, Seoul, Korea;3. Electronic Materials Research Center, Korea Institute of Science and Technology (KIST), Seoul, Korea |
| |
| Abstract: | 0.96(Na0.5K0.5)(Nb1?xSbx)‐0.04SrZrO3 ceramics with 0.0≤x≤0.06 were well sintered at 1060°C for 6 hours without a secondary phase. Orthorhombic‐tetragonal transition temperature (TO‐T) and Curie temperature (TC) decreased with the addition of Sb2O5. The decrease in TC was considerable compared to that in TO‐T, and thus the tetragonal phase zone disappeared when x exceeded 0.03. Therefore, a broad peak for orthorhombic‐pseudocubic transition as opposed to that for orthorhombic‐tetragonal transition appeared at 115°C‐78.2°C for specimens with 0.04≤x≤0.06. An orthorhombic structure was observed for specimens with x≤0.03. However, the polymorphic phase boundary structure containing orthorhombic and pseudocubic structures was formed for the specimens 0.04≤x≤0.06. Furthermore, a specimen with x=0.055 exhibited a large piezoelectric strain constant of 325 pC/N, indicating that the coexistence of orthorhombic and pseudocubic structures could improve the piezoelectric properties of (Na0.5K0.5)NbO3‐based lead‐free piezoelectric ceramics. |
| |
| Keywords: | crystals/crystallization electroceramics piezoelectric materials/properties sinter/sintering |
|
|
