| Electric properties of unmodified BiFeO3-BaTiO3 ceramics system |
| Dajeong KIM |
| Changwon Nat¡¯l University |
|
BiFeO3–BaTiO3 (BF–BTx) solid solution bulk ceramic is presented as potential lead-free piezoelectric ceramic. The phase diagram of BF-BTx material show morphotropic phase boundary (MPB) at x = 33 mol% region, which is coexistence of both rhombohedral (BiFeO3) and tetragonal (BaTiO3) phase, the result of excellent piezoelectric properties in BF-BT33 system can be expected [1,2]. For the piezoelectric application, it is needed for the Multi-layer ceramic capacitor (MLCC) made by using tape casting or screen printing process. Fujii and co-workers reported Mn-modified BF-BT-Bi(Mg,Ti)O3 ternary ceramics, however, unmodified BF-BT based ceramics have not been achieved yet [3]. We have investigated 0.67BF-0.33BT (BF-BT33) ceramic prepared using tape casting method showed high Tc, of ~ 470 oC, and piezoelectric constants d33 and d33* were 163 pC/N and 260 pm/V in ceramics quenched at temperature of 960 oC.
Figure 1(a) Ferroelectric hysteresis loops and (b) The S- E curves of unmodified BF-BT ceramic
References:
[1] M. M. Kumar, A. Srinivas, and S. V. Suryanarayana, J. Appl. Phys. 87, 855 (2000).
[2] D. J. Kim, M. H. Lee, J. S. Park, M-H. Kim, T. K. Song, S. W. Kim, W-J. Kim, K. W. Jang, S. S. Kim, D. Do, J. Electrom. online published (2014) DOI: 10.1007/s10832-014-9912-6.
[3] I. Fujii, R. Mitsui, K. Nakashima, N. Kumada, M. Shimada, T. Watanabe, J. Hayashi, H. Yabuta, M. Kubota, T. Fukui, and S. Wada, Jpn. Jour. Appl. Phys. 50, 09ND07 (2011)
|
| Acknowledgements : This work was supported by the National Resarch Foundation of Korea [KRF] grant funded by the Korea government [MSIP] (2012-0007403, and 2012-0009457) and by the Priority Research Centers Program through the National Research Foundation of Korea (NRF) funded by the MEST (2013R1A1A4A01010612, 2012-045424) and by the Technology Innovation Program (10047914, Development of ¡°Lead-free¡± Piezoelectric Materials of Electromechanical Coupling Factor k33 > 0.85) funded by the Ministry of Trade, Industry and Energy (MOTIE, Korea). |
|
