Sintering behavior and microwave dielectric properties of 0.67CaTiO3–0.33LaAlO3 ceramics modified by B2O3–Li2O–Al2O3 and CeO2

Abstract

A low temperature sintering method was used to avoid the relatively high sintering temperatures typically required to prepare 0.67CaTiO3–0.33LaAlO3 (CTLA) ceramics. Additionally, CeO2 was introduced into the CTLA ceramics as an oxygen-storage material to improve their microwave dielectric properties. 0.67CaTiO3–0.33LaAlO3 ceramics co-doped with B2O3–Li2O–Al2O3 and CeO2 were prepared by a conventional two-step solid-state reaction process. The sintering behavior, crystal structure, surface morphology, and microwave dielectric proprieties of the prepared ceramic samples were studied, and the reaction mechanism of CeO2 was elucidated. CTLA+0.05wt% BLA+3wt% CeO2 ceramics sintered at 1360°C for 4h exhibited the optimal microwave dielectric properties: dielectric constant (εr)=45.02, quality factor (Q×f)=43102GHz, and temperature coefficient of resonant frequency (τf)=2.1ppm/°C. The successful preparation of high-performance microwave dielectric ceramics provides a direction for the future development and commercialization of CTLA ceramics.