The 0.95MgTiO3-0.05CaTiO3 (95MCT) powders and ceramics were prepared by a sol-gel method by using Mg(NO3)2•6H2O, Ca(NO3)2•4H2O and Ti(C4H9O)4 as the starting materials. The effects of calcination temperature on phase formation, morphology and particle size distribution of the proposed powders were examined, and the microwave dielectric properties of 95MCT ceramics made from different size particles were investigated. The dried gels were calcined at 600 °C, 700 °C, 800 °C and 900 °C, and the derived particle sizes of powders were 10-20 nm, 50-100 nm, 60-120 nm and 120-150 nm, respectively. The proper sizes, which range from 50-150 nm, lowered the sintering temperature of 95MCT ceramics effectively from 1400 °C to 1175 °C due to the high surface energy. Sintered at 1175 °C, the 95MCT ceramic prepared from 50-100 nm size particles had compact structure and exhibited good microwave dielectric properties: εr = 21.33 and Q×f = 36,315 GHz.
