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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. [ABSTRACT FROM AUTHOR]

In this work, a silicate ceramic, CaY2Al4SiO12 (CYASO), with a low dielectric constant and low loss was prepared using traditional solid-state methods. X-ray diffraction (XRD) refinement analysis shows that the CYASO material crystallized into a phase with an Ia-3d space group and an impurity peak. The orthogonal cubic structure of the CYASO ceramic was confirmed through transmission electron microscopy (TEM), and the structure exhibited an orderly layered arrangement. The internal microstructure was characterized using scanning electron microscopy (SEM), which showed that the sample's relative density reached 97.8%. We discuss the correlation between the full width at half maximum (FWHM) of the Raman matrix corresponding to the vibration mode of the symmetric bending mode of AlO4 at the Raman shift of 855 cm−1 and the Q × f value. Additionally, the analysis focused on the various factors that influence the dielectric constant, including density, secondary phase, and porosity changes. The ceramics exhibited remarkable microwave dielectric properties (εr = 8.7, Q × f = 34,700 GHz, τf = −35 ppm/°C) when calcined at 1425°C. CYASO ceramic shows great capacity as a microwave dielectric material. [ABSTRACT FROM AUTHOR]