PREPARATION AND DIELECTRIC-PROPERTIES OF LOW-TEMPERATURE-SINTERABLE (ZR0.8SN0.2)TIO4 POWDER

Low-temperature-sinterable (Zr0.8Sn0.2)TiO4 powders were prepared usin g 3 mol% Zn(NO3)(2) additive and then compared with powders prepared u sing 3 mol% ZnO additive and no additives. Sintering at 1200 degrees C for 2 h produced a dielectric ceramic with rho = 98.6% of theoretical density (TD), epsilon(r) = 38.4, Q x f (GHz) = 42000, and tau(f) = -1 ppm/degrees C. Sintering at 1250 degrees C resulted in an excellent d ielectric with rho = 99% of TD, epsilon(r) = 40.9, Q x f (GHz) = 49000 , and tau(f) = -2 ppm/degrees C. Scanning electron microscopy showed a microstructure with grains measuring 0.5 to 1 mu m, and transmission electron microscopy revealed secondary phase in the grain boundaries.