Non-stoichiometrically activated sintering of Ca_0.8Sr _0.2TiO₃

The two dissimilar dopants, Li₂Si₂O₅ with small ionic sizes and inert Ag with a large atomic size were selected to understand the effects of activators on non-stoichiometrically activated sintering of Ca_0.8Sr_0.2TiO₃ by doping with Ag, or co-doping with Ag and Li₂Si₂O₅. The solubility limit of Ag⁺ in Ca_0.8Sr_0.2TiO ₃ was ca. 7.0 mass%. The optimum sintering temperature was as low as 1353 K by co-doping of 5.0 mass% Ag and 0.5 mass% Li₂Si ₂O₅. This firing temperature was lower than that of 1623 K using 5.0 mass% Ag, and 1473 K for 0.5 mass% Li₂Si₂O ₅, respectively. The fracture strength of 363 MPa attained by co-doping was much high than the values of 291 and 292 MPa using 5.0 mass% Ag and 0.5 mass% Li₂Si₂O₅, respectively.