Low-temperature sintering of Mg2SiO4 ceramics with CaO–TiO2–P2O5 additive for enhanced microwave dielectric properties

Dielectrics with a high-quality factor (Q×f) and low dielectric constant (εr) are ideal for high-speed data transmission. Silicate-based Mg2SiO4 (forsterite) exhibits a low εr and high Q×f because silicon-oxygen tetrahedra are composed of half covalent bonds. In this study, 43.75CaO–25TiO2–25P2O5 (CTP) was used as a sintering additive to reduce the sintering temperature. Despite forsterite Mg2SiO4 ceramics firing at high temperatures and possessing a large negative temperature resonant frequency. Following that, this research focuses on reducing the sintering temperature of Mg2SiO4 by using a sintering additive of 43.75CaO-25TiO2-25P2O5 (CTP). The traditional solid-state conventional method was used to synthesize low permittivity of Mg2SiO4 and exhibited an orthorhombic phase with a space group of Pbnm. Further, glass ceramic composite crystallinity, grain size, microstructure, types of bonds, and modes of ceramics were investigated via XRD, SEM, TEM, FTIR, and Raman analysis. Varying CTP content (1–7 wt%) influenced microstructure and dielectric properties. Thus, an appropriate amount of 5 wt% CTP-doped sample exhibited reduced sintering temperature (1300 → 1150 °C) and revealed good microwave dielectric properties of εr = 6.6, Q×f = 13807.92 GHz, and τf = − 40 ppm/°C, making it suitable for microwave applications.