| With the rapid development of microwave communication and radar technologies,researches on microwave dielectric resonant materials have been drawn toward high band of microwave frequency application. In recent years, MgTiO3–CaTiO3 ceramics has been became research focus in today's academic circles because it has advantages such as rich of raw mate- rials and low cost, and it is well known as the materials for temperature compensating type capacitor and dielectric resonator, but the sintering temperature is higher and ceramic dielectrics need to be improved,the development is limited. Many researchers made efforts to reduce the sintering temperature and optimizing the dielectric properties .95MCT ceramic is choosed as research object. The conventional solid-state is used for preparation 95MCT ceramic, A and AB site ions codoped effects on the sintering temperature, microstructure and dielectric properties of 95MCT ceramics were studied. The results show:(1) A site ions codoped :The density of Li-La and Sb-Sr codoped can be improved , and reduced the sintering temperature.Sb-Sr codoped can effectively lower the sintering temperature to 1250℃, and adjust the temperature coefficient of dielectric constant,The 95MCT ceramics get the best dielectric properties when x=0.03 mol:εr =21.76, tgδ=8.21×10-4,αc =1.3×10-6.(2) AB site ions codoped: Li-Nb,Li-W,Sb-Sn,Zn-Nb,Sb-Zr, Zn-Sn and Zn-W codoped are investigated.Seven groups of codoped ions can reduced the sintering temperature, adjusted the temperature coefficient of dielectric constant, optimized the dielectric properties at differ- ent extent. Li-Nb,Li-W and Zn-W codoped can prevent the middle phase from formation. Li-Nb and Zn-Sn codoped can effectively reduced the sintering temperature below to 1230℃, the sintering temperature of Sb-Sn codoped is slightly larger than 1320℃.Zn-W codoped can effectively reduced the dielectric loss to 10-5 orders of magnitude .The temperature coefficient of dielectric constant of Li-Nb codoped get the Minimum value for 10-6,and the rest of ceramics were 10-5 orders of magnitude.
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