Enhanced Sinterability and Microwave Dielectric Performance of (1-x)ZnAl2O4-xLi4/3Ti5/3O4 Ceramics

(1 - x)ZnAl2O4-xLi(4/3)Ti(5/3)O(4) (ZALT) (x = 0.2, 0.4, 0.6, 0.8) microwave dielectric ceramics were prepared by a solid state reaction method. The preparation, sintering behavior, phase composition and microwave dielectric properties of ZALT ceramics were investigated. ZnAl2O4 could not form a solid solution with Li4Ti5O12. With x increasing from 0.2 to 0.8, the phase compositions of ZALT ceramics changed: (ZnAl2O4 and Li2ZnTi3O8, x = 0.2, 0.4) -> (ZnAl2O4, Li2ZnTi3O8 and Li4Ti5O12, x = 0.6) -> (Li2ZnTi3O8 and Li4Ti5O12, x = 0.8), and the main phase changed from ZnAl2O4 (x = 0.2, 0.4) to Li2ZnTi3O8 (x = 0.6, 0.8). With increasing x values, the sintering temperature was reduced from 1250A degrees C to 1100A degrees C. ZALT ceramics exhibited microwave dielectric properties with epsilon (r) of 13.0-29.0, Q x f values of 30,220-65,580 GHz and tau (f) values of -51.4 ppm/A degrees C to -20.9 ppm/A degrees C.