Microwave dielectric properties of (0.75ZnAl2O4–0.25TiO2)–MgTiO3 ceramics prepared using digital light processing technology

Abstract

AbstractZTM ceramics comprising of 0.75ZnAl2O4–0.25TiO2 and MgTiO3 at a ratio of 90:10 wt.% are widely used in the field of communication as filters and resonators owing to their excellent microwave dielectric properties. However, the development of such dielectrics with complex structures, as required by microwave devices, is difficult using traditional fabrication methods. In this study, ZTM microwave dielectric ceramics were prepared using the digital light processing (DLP) technology. The influence of the sintering temperature on the phase composition, microstructure, and microwave dielectric properties of ZTM ceramics was investigated. Results showed that with an increase in the sintering temperature, the dielectric constant (εr) and quality factor (Q × f) of ZTM ceramics initially increased owing to the increase in the density and diffusion of ions. However, when the sintering temperature was excessively high, the abnormal growth of crystal grains and micropores led to a decrease in εr and Q × f. The ZTM ceramics sintered at 1450°C exhibited the optimum microwave dielectric properties (εr = 12.99, Q × f = 69 245 GHz, τf = −9.50 ppm/°C) owing to the uniform microstructure and a high relative density of 95.02%. These results indicate that DLP is a promising method for preparing high‐performance microwave dielectric ceramics with complex structures.