With the help of the first principle calculation, the solid-state reaction experiment was conducted to investigate the alteration in the sintering and the microwave dielectric properties of Mg₃B₂O₆ ceramic with many Zn²⁺ substitutions. These properties were characterized using the scanning electron microscopy, network analyzer, X-ray diffraction, Raman spectroscopy, energy-dispersive spectroscopy, and thermomechanical and differential-thermal analyses. The coexistence of Mg₃B₂O₆, Mg₂B₂O₅ and ZnO ceramics could be observed with increasing Zn²⁺ addition, and the lattice distortion occurred in the Mg₂B₂O₅ and Mg₃B₂O₆ ceramics due to the substitution of Mg²⁺ with Zn²⁺. The electron density and the bond property of the MgO₆ octahedron changed, and a quantitative method was used to discuss the variation in sintering, substitution and phase formation properties. The densification window was decreased to 1100 °C, and the dielectric properties improved with the formation of a three-phase borate solid solution (dielectric constant = 6.73, quality factor = 112,000 GHz at 16 GHz (Q = 7000), temperature coefficient of resonant frequency = −61.2 ppm °C⁻¹, and relative density = 97.0%).

With the support of density functional theory (DFT) calculation, the amelioration of sintering and dielectric properties of the Mg₃B₂O₆ (MBO) ceramic was realized through the substitution of magnesium with nickel. The TE-mode cylindrical cavity method was used to measure the dielectric properties at different frequencies. The thermo-mechanical analysis and simultaneous thermal analysis were used to characterize the chemical and mechanical properties. The phase composition was determined through the X-ray diffraction (XRD) and Raman spectrum. The microstructure was investigated using the scanning electron microscopy (SEM). Magnesium substitution with nickel (4 mol%) could ionize the B-O bond of BO₃, modify the vibration mode, improve the order degree, densify the microstructure, decrease the intrinsic densification temperature, and ameliorate the dielectric properties of the MBO ceramics. The maximum values were achieved for the ceramics with 4 mol% nickel and sintered at 1175 ℃, that is, 97.2% for relative density, 72,600 GHz (10 GHz), 75,600 GHz (11.4 GHz), and 92,200 GHz (15 GHz) for Q × f, 7.1 (10 GHz), 7.01 (11.4 GHz), and 6.91 (15 GHz) for ε_r, and -56.3 ppm/℃ for τ_f.