Low temperature sintering lithium-based microwave dielectric ceramics and preparation method thereof

The invention discloses low temperature sintering lithium-based microwave dielectric ceramics and a preparation method thereof. A chemical composition formula of the dielectric ceramics is Li2CoTi3-x-yZrxSnyO8, wherein x is no less than 0.00 and no more than 1, and y is no less than 0.00 and no more than 2. The preparation method comprises the following steps of weighing and proportioning original powder of Li2CO3, Co2O3, TiO2, XnO2 and ZrO2 with the purity above 99.9 percent based on the chemical formula of Li2CoTi3-x-yZrxSnyO, wherein x is no less than 0.00 and no more than 1, and y is no less than 0.00 and no more than 2; and wet type ball milling and mixing for 12-24h, using distilled water as a solvent, preburning for 4-8h in the air atmosphere of 90 DEG C after drying, adding binderin preburning powder, pressing and forming after granulation, and sintering for 1-3h in the air atmosphere of 950-1100 DEG C. Polyvinyl alcohol solvent with the mass concentration of 5 percent is adopted as the binder, and the dosage of the binder accounts for 3-15 percent of the total quantity of the original powder. The sintering temperature of ceramic materials is lower than 1100 DEG C, the high frequency dielectric constant reaches 25-40, a Q*f value reaches 24000-53000GHz, and the resonant frequency temperature coefficiency (tau f) is small and favorable.