The effects of B₂O₃ addition on the sintering behaviour of BaTiO₃-CaTiO₃ (BCT) materials were investigated. (1-x) BaTiO₃-x CaTiO₃-y B₂O₃ (where x is 3 or 7 % mol. and 0 ≤ y ≤ 3 mol.% respectively). Pellets were prepared from BaTiO₃ (BT) and CaTiO₃ (CT) powders mixture and sintered at 1,200, 1,250, 1,300 and 1,350 ^oC, gradually in air for 3 h. The relative density of BCT samples with 1 mol. % B₂O₃ sintered at 1,200 ^oC were as good as those of undoped BCT sintered at 1,350 ^oC. When > 2 mol. % B₂O₃ was added to BCT, the over doped B₂O₃ did not form a liquid phase or volatilize, it remained in the samples and formed a secondary phase that lowered the sintering behaviour of the BCT. The X-Ray diffraction analysis carried out on both kind of pellets (x = 0.3 and x = 0.7) revealed the presence of BT and CT solutions together in an unidentified secondary phase.

Keywords: BaTiO₃, CaTiO₃, B₂O₃, Sintering, Relative density, X-Rays diffraction