Diffuse Phase Transition of Ba_0.92Ca_0.08(Ti_0.82Zr_0.18)O₃ Based Ceramics

Abstract

Ba_0.9175Ca_0.08Nd_0.0025(Zr_0.18Ti_0.8175-xY_xMn_0.0025)O₃(x = 0, 0.5%, 0.75%, 1.0%, 1.5% and 2.0% mol) ceramics are synthesized by the conventional solid state processing. X-ray diffraction patterns show that all the compositions have an only tetragonal BaTiO₃ structure at room temperature. The dielectric constant of samples decrease, dielectric peak temperature (T_m ) shifts toward lower temperature and the frequency dispersion becomes strong and the more pronounced DPT (Diffuse Phase Transitions) behavior as the content of Y increases. The degree of deviation from the Curie–Weiss law is found to increase and the value of the parameter γ is from 1.82 to 1.96 with the increasing amount of Y³⁺.

Keywords:

• Ceramics
• dielectric properties
• relaxor behavior
• diffuse phase transition

Acknowledgments

The work was supported by National Natural Science Foundation of China under Grant No 11074203; Key Disciplinary of Materials Science under Grant No XZD0814-09-1, the talents foundation of Xihua University under Grant No R0620109 and the Graduate Innovation Foundation of Xihua University under Grant No. YCJJ201152 and YCJJ201257.