B2O3 as an effective additive for cold sintering of MgTiO3

In the present study, B2O3 has been introduced as an effective additive for the cold sintering of MgTiO3 as a microwave dielectric ceramic. Furthermore, the effects of various cold sintering parameters, including cold sintering temperature, post-annealing temperature, sintering process time, and B2O3 quantity have been investigated. The results proved that high-quality samples with a relative density of more than 96% can be obtained by using 15 wt% B2O3 and cold sintering at 200 oC under an applied pressure of 250 MPa for 1 h and post annealing at 1100 oC. X-ray diffraction (XRD) analysis confirmed the absence of any reaction between the two phases. Moreover, the MgTiO3- 15 wt.% B2O3 ceramics show excellent microwave dielectric properties, including a low relative permittivity (εr) of 14.5, a high-quality factor (Q×f) of 39,000 GHz, and a temperature coefficient of frequency (TCF) value of −54.36 ppm/°C.