Thermal, mechanical, and dielectric properties of Gd₂O₃ doped cordierite ceramics

In this study, we utilized the solid-state synthesis method to prepare a Gd₂O₃-doped cordierite ceramic (0–12.5 wt%). Our objective was to investigate the effects of Gd₂O₃ doping on various properties, including phase composition, microstructure, sintering characteristics, thermal expansion, mechanical strength, and dielectric properties of cordierite ceramics. Our findings indicated that the introduction of Gd³⁺ ions had a significant impact on the formation of the cordierite phase, the reduction of spinel impurity, and the growth of grain size, leading to a decrease in the coefficient of thermal expansion. As the amount of Gd₂O₃ doping increased, the coefficient of thermal expansion decreased from 2.91 × 10^–6/°C to 2.15 × 10^–6/°C. We achieved the highest flexural strength of 68.54 ± 2.36 MPa in cordierite ceramic doping with 10 wt% Gd₂O₃ due to optimal densification. Moreover, the quality factor increased from 30,400 GHz to 64,800 GHz, and the dielectric constant ranged from 4.08 to 6.19.