Microwave properties and microstructures of LaTiO3 stabilized with NiO

(1-x)La 2/3 TiO 3 -xTiNiO 3 ceramics with x ranging from 0.01 to 0.2, were elaborated by conventional solid-state reaction starting from TiO 2 , La 2 O 3 , and NiO powders. These compositions have been identified as secondary phases detected in (Zr,Sn)TiO 4 ceramics sintered with La 2 O 3 and NiO. Microwave resonators were sintered at temperatures ranging from 1340 to 1380 C. These sintering temperatures have been determined taking into account thermodilatometric data. Microwave dielectric properties and microstructures were investigated. Perovskite phase La 2/3 TiO 3 was identified by XRD, SEM and EDS together with minor phases. Dielectric constants are in the 50-70 range and QF values, measured at 3 GHz, are close to 20 000 GHz. One significant composition is characterized by k = 69 and QF= 17,000 GHz at 3 GHz.