Fabrication nanopowders by high-energy ball-milling and low temperature sintering Li_2TiO_3 microwave dielectrics

摘要

In this study, Li_2TiO_3 nanopowders were synthesized via a high-energy ball-milling process followed by calcinations and Li_2TiO_3 ceramics were fabricated by solid-state reaction. The microstructure and microwave dielectric properties of Li_2TiO_3 ceramics were also investigated systematically. Li_2TiO_3 nanopowders with an average particle size of 86.7 nm were derived at 600 ℃ for 2h. X-ray diffraction patterns exhibited that single monoclinic structure of the Li_2TiO_3 ceramics were obtained at an optimum sintering temperature of 1000 ℃ for 2 h by using low temperature synthesis nanopowders as a precursor. The samples of Li_2TiO_3 ceramics with grain sizes in the range of 1.5-5.0 μm showed dense microstructures and excellent microwave dielectric properties (ε_r=16.4, Q×f=54,326 GHz, τ_f=27.4 ppm/℃). All these results illustrated that high-energy ball-milling method is a simple and practical route to produce Li_2TiO_3 ceramics for microwave applications.