Dielectric behavior of TiO2 ceramic prepared by plasma activated sintering

Rutile-phase TiO2 ceramic was rapidly fabricated by plasma activated sintering (PAS) at 650–850 °C for 3 min under 30 MPa. The temperature and frequency dependences of the dielectric properties (dielectric constant and dielectric loss) for the dense TiO2 ceramic were investigated, and the dielectric behavior was briefly discussed. It was demonstrated that extraordinarily high dielectric constant (2–5 × 104) was observed in the whole experimental ranges of − 160 to 200 °C and 1 kHz–1 MHz. Moreover, the dielectric loss kept a relatively normal level, however, its temperature and frequency dependences were markedly different with those of the rutile-phase TiO2 preforms. The unusual dielectric behavior was related with the particular dielectric polarizations of the TiO2 ceramic and its dominant form of loss under different conditions.

► A dense and pure TiO2 ceramic is prepared rapidly by plasma activated sintering process. ► We investigate systemically the temperature and frequency dependences of the dielectric properties for the TiO2 ceramic. ► We discuss the dielectric behavior. ► Extraordinarily high dielectric constant (2–5 × 104) is observed.