Microwave dielectric properties and crystal structure of a new low loss BaCa13Mg2(SiO4)8 ceramics
摘要
This investigation explores the microwave dielectric characteristics of BaCa13Mg2(SiO4)8 ceramics, synthesized through conventional solid-state techniques. Via X-ray diffraction analysis and comprehensive data refinement across various temperatures, we unequivocally determined the orthorhombic crystal structure of the BaCa13Mg2(SiO4)8 ceramics. The measured lattice parameters at a sintering temperature of 1345 °C are a = 18.51543 Å, b = 6.77482 Å, and c = 10.95537 Å, with a corresponding unit volume of V = 1374.226706 Å3. The microstructure of the ceramic grains was studied in detail by scanning electron microscopy (SEM), and it was found that the optimum relative density was 97.2%. The study further explored the effects of porosity, packing fraction, relative density, and the impact of Si–O bond valence (VSi-O) on the microwave dielectric characteristics of BaCa13Mg2(SiO4)8 ceramics. Remarkably, the BaCa13Mg2(SiO4)8 ceramics exhibited exceptional performance metrics (εr = 11.53, Q × f = 15,231 GHz (f = 10.6 GHz), τf = − 27.3 ppm/°C) at 1345 °C, establishing it as a promising candidate for microwave applications.