Li_2ZnTi_3O_8 Microwave Dielectric Ceramics Prepared by the Reaction-Sintering Process

摘要

Li_2ZnTi_3O_8 ceramics were prepared by reaction-sintering process (calcination free). The crystal phase and microstructure were investigated using X-ray diffraction (XRD) and scanning electron microscopy (SEM). A pure phase of Li_2ZnTi_3O_8 ceramics sintered at 1075° ~ 1150°C with cubic spinel structure was confirmed by XRD. The microwave dielectric properties (ε_r Q×f) of the ceramics were strongly dependent on the densification and grain size. The τ_f of the ceramics was almost independent with the sintering temperatures. In particular, Li_2ZnTi_3O_8 ceramics by reaction-sintering method sintered at 1125 °C for 5 h exhibited good combination microwave dielectric properties of ε_r=21.7, Q×f=70 500 GHz (at 7.5 GHz) and τ_f=-13 ppm/°C.