Preparation and Microwave Dielectric Properties of xBaZn_2Ti_4O_(11)-(1-x)BaNd_2Ti_4O_(12) Ceramics

摘要

xBaZn_2Ti_4O_(11)-(l-x)BaNd_2Ti_4O_(12) (x = 0.18-0.30) ceramics were prepared by solid-state reaction method and their microwave dielectric properties were investigated with the purpose of finding a microwave ceramics with high dielectric constant (ε_r), high quality factor (Q×f) and zero temperature coefficient of resonant frequency (τ_f).The two phase system BaZn_2Ti_4O_(11)-BaNd_2Ti_4O_(12) affected the unit cell volume and the microstructure, the microwave dielectric properties (ε_r, Q×f, τ_f). As increasing x from 0.18 to 0.30, the main phase composition was BaNd_2Ti_4O_(12). Therefore, the ε_r decreased from 64.9 to 60.3 and the Qxf values raised from 11,350GHz to 13,210GHz, and the τ_f values decreased from 7ppm/° to -5ppm/°.The 0.22BaZn_2Ti_4O_(11)-0.78BaNd_2Ti_4O_(12) ceramics sintered at 1250°C for 4 h displayed the best dielectric constant ε_r,Q×f and Tf, as 63.9, 12380 GHz and -0.1 ppm/° respectively.